SOIL DEGRADATION AND CONSERVATION
Soil degradation is the deterioration (destruction) of the quality of the soil through the loss of fertile, pollution, and erosion and mass wasting.
Degradation renders soil useless for human development activities and unfit for the life of the biota.
Loss of soil fertility
This refers to the decline in the soil ability to support plant growth through the failure to provide necessary nutrient for plant growth.
Loss of fertility can be caused by:
1. Leaching process, this washes down the necessary nutrient in solution from the top soil. It makes soil become more acidic and hence toxic. It is common in areas, which are humid, and experience heavy rains.
2. Over cultivation in certain area as a result of the rapid population growth. The crops grown on the same piece of land for a long time leads to the depletion of soil nutrients.
3. Monoculture that involves the cultivation of crops without crop rotation or inter cropping .The nutrient are used up without replacement and the soil structure can be destroyed (soil becomes unstable).
4. Soil pollution due to the excessive use of chemical like pesticides and artificial fertilizers, dumping of harmful wastes in the soil and acid rain which make the soil toxic, structure less and hence unproductive.
5. Soil erosion accelerated by poor land management like deforestation, flat cultivation on the slope etc.
6. Mass wasting that leads to the loss of upper layer of the soil and its Nutrients.
7. Severe loss of soil water due to excessive vapor transpiration especially in the arid and semi arid areas.
Soil erosion is the wearing away, detachment and removal of soil material from one place to another place through the agents like water, wind and ice .Two types of erosion are often distinguished as:
Normal Geological Erosion
It’s the widespread type of erosion that occurs wherever there is a natural flow of energy and matter on the earth’s surface without man’s influence .It is fortunately very slow and so not normally injurious to the soil cover of the world.
More often than not, its rate is either slower or equal to the soil formation hence its effect are rarely noticeable. Erosion under this category is easy to control.
Accelerated Soil Erosion
Is the type of erosion associated with man’s activities (man induced). It is spectacular in nature (very destructive), therefore it has attracted man’s attention .Its side effect include physical loss of soil nutrients, leading to severe economic loss arising from the reduced crop yield or total crop failure, and/or wasted effort and money spent on unsuccessful soil-conservation projects.
Factors that affecting (Controlling) Accelerated Soil Erosion
There are factors which can accelerate or decelerate the rate of soil erosion.
1. Physical Factors;
· Climate: Where there is heavy rainfall erosion tends to be severe while where there is low rainfall erosion is also low.
· Topography: On steep slope soil erosion can be high while on the gentle slopes the rate of erosion tends to be low.
· Nature of soil: This depends on its characteristic features like texture, structure, permeability etc. Unstable soils with coarse Texture are prone to severe erosion compared to the fine textured stable soils.
· Vegetation cover: Where there is dense vegetation soil erosion is checked. But where is scanty or no vegetation soil erosion take place easily.
2. Human Factors;
1. Good management of the soil which involves the way human being uses the soil wisely and skillfully and undertaking conservation measure to reduce or mitigate erosion through afforestation, terracing, strip cropping, crop rotation, contour ploughing, inter cropping and restocking.
2. Poor management that involve injudicious (unwise use of the soil through over cultivation, mono-cropping flat cultivation over-grazing and deforestation).
3. The increase in population leads to over exploitation of resources especially minerals, forest and over cultivation.
Agents of Soil Erosion
Water is the most important agent of soil erosion. The erosion by water Involves:
· Splash erosion: caused by rain drops.
· Sheet erosion: which involves the removal of the uniform cover of the soil, by surface run-off on gentle slopes.
· Rills erosion: that leads to the formation of same channels called rills on the surface.
· Gully erosion: that leads to the formation of deep troughs called gullies due to severe undercutting.
· River erosion: take place in the specific channels called river valleys.
Wind is another agent of soil erosion. It takes place in arid and semi-arid or where the soil is loose Gravity leads to the gradual movement of weathered material down the slope without involving transport agent. The spontaneous Material movement causes soil erosion. It is influenced by the nature of slope.
Human Activities which can Cause Soil Erosion
1. Poor cultivation methods like mono cropping (monoculture) flat Cultivation splash and burn in shifting cultivation.
2. Mining which leads to the creation of pit, deforestation etc.
3. Construction activities like building houses, establishing roads, etc. excessive cutting trees for lumbering and source of fuel. This causes the loss of vegetation species (deforestation).
4. Overgrazing which leads to the destruction of grass, leaving the land bare and hence exposed to erosional agents.
5. Casual Burning of vegetation to encourage fresh grass, which can Be good for pasture. This is common in the tropical areas.
Effects of soil Erosion
Soil erosion leads to the following effects;
1. Pollution of water bodies due to the introduction of material eroded from the surrounding areas. Some of the materials are toxic in nature.
2. Loss of fertility which in turn causes the reduction in yields or total crop failure. This can then lead to the occurrence of famine and death of people.
3. Migration of people from areas, which have been affected to the areas, which have not been affected by erosion.
4. Over flooding of the rivers as a result of the creation of the small channels leading to the river systems.
5. Deforestation as a result of the death of plants due to the loss of soil.
6. Reduction in the size of the arable land. This leads to poor crop production since people concentrate on a smaller land that is not sufficient.
7. Loss of the habitat as a result of deforestation caused by the loss of soil.
8. Soil erosion can accelerate rock weathering by exposing the underlying rock to the weathering agents like temperature etc.
9. It leads to the costs incurred in during the process of conserving the soil, which has been eroded.
10. Soil erosion can destroy transport and communication systems like roads, railway line and telephone posts.
11. It can lead to the destruction of houses rendering people homeless. Important economic schemes can be destroyed such as tourist resorts when the hotels collapse and decline of the irrigation schemes. This can contribute to the escalation of poverty.
Soil pollution refers to the introduction or presence of any substance in the soil which adversely affect the soil quality. The substance which pollutes the soil is called a pollutant.
Sources of Soil pollution
Pollution can be from the atmosphere, industries, home stead and agriculture areas.
1. From the atmosphere: The pollutants are introduced through the acid rain. These make the soil become acidic and hence destroy the soil structure and killing the plant. Acidic rain is predominant in the industrialized areas like Germany.
2. From the industries: Some chemicals, radioactive material can be introduced into the soil and render the soil unfit for agriculture. Some of the chemicals are poisonous therefore they kill plants after getting into the soil.
3. From the homesteads: Some wastes like metal materials, bottles, plastic bags, cans etc lead to the pollution of the soil.
4. From the Farms: Chemicals like pesticides e.g. DDT, crop remains, fertilizers can be produced and get into the soil under the influence of rainfall.
5. Irrigation: agriculture encourages the accumulation of salt (Stalinization) in the upper soil layer .Also agricultural activities can cause negative pollution of soil through the depletion of vegetation.
Effect of Soil Pollution
1. Decline in fertility because of addition leading to the decline in crop production.
2. Destruction of soil structure and texture.
3. Death of soil biota (organisms), which are very important in the decomposition of organic matter.
4. It can lead to water logging or flooding due to poor drainage. It interferes with aeration making the soil unproductive.
5. It makes man incur a lot of costs when trying to fight against the problem of soil pollution. For example liming for reducing acidity in the soil and flushing so as to reduce soil salinity.
6. Soil pollution can also lead to people’s migration to the areas, which are not affected by pollution.
7. Crop failure yields caused by pollution leads to the occurrence of famine, which in turn causes poor health, and death of people.
Soil Management and Conservation
Soil management: refers to the skillful or wise use and control of the quality of the soil (land) resource.
Soil conservation: refers to the process of preserving the soil for proper and sustainable use.
Why Undertake Soil Conservation?
1. To maintain the quality of the land preventing it to get exhausted and become totally unproductive.
2. To improve or restore the quality of the land where there has been exhaustion as to promote production.
3. To get more land and produce more products for satisfying the burgeoning population in the countries.
4. To ensure that the coming generation can benefit from the same land used today.
Conservation methods include the following:
1. Educating people so as to promote the land management ideas among the people. This should be undertaken by the government and some committed individuals.
2. Training and encouraging the farmers to use proper farming methods like crop rotation, inter cropping, use for organic manure, Strip cropping, Contour ploughing and deep ploughing.
3. Planting of cover crops, afforestation and reforestation in order to check soil erosion by reducing the speed of water on the surface.
4. Reducing and stopping the use of pesticides like dieldrin, DDT, and artificial fertilizers, which tend to destroy the soil.
5. Recycling of wastes rather than dumping them into the soil.
6. Restocking in order to avoid overgrazing that leads to the destruction of grass.
7. Encouraging dry farming that involves mulching in order to reduce Loss of water through excessive evaporation especially in the dry areas.
8. Land filling with brushwood should be used where the soil has been severely eroded production gullies.
9. The population should be controlled so as to discourage the excessive exploitation of resources, which leads to land degradation.
10. Alternative sources of energy should be explored and used to avoid the excessive use of forest materials and oil, which cause hazard to the environment.
11. Radioactive materials should be dumped very deep in the soil to prevent the upper soil layer from being highly affected.
12. Terracing, construction of stone lines (in Burkina Faso) and check dams (in China) so as to control the movement of water and force to get into the ground rather than flowing like the surface run-off.
13. Developing other economic activities rather than depending on agriculture only especially in the developing countries.
14. The government should formulate good policies which advocate community participation, land tenure and encourage the proper use of the land. Where possible people should be given financial support so as to invest in scientific agricultural techniques (which are not precarious to the soil.)
SOIL CONSERVATION IN THE USA
Soil erosion has been a major problem in the USA and the TENNESSEE Valley is a renowned area in the world where severe problem of erosion has been successfully controlled. The River Tennessee is a tributary of River Ohio, which in turn is a tributary of the Mississippi. The river drains through many states in USA.
Soil Erosion which used to be a Menace in the Areas was caused by:
1. Deforestation as the land was cleared for cultivation. Clearing of the forest propelled by the growth of population in the area.
2. Periodic flooding during the rainy season resulting from the surface run-offs from the Application Mountains.
3. Poor farming methods like monoculture where were practiced in the area especially growing of corn and cotton.
4. Steep slope of the Appalachians accelerated erosion. These entire plus the problems of silting and disease like malaria led to the decrease in agricultural production.
To control soil erosion along the Tennessee Valley the US
Government established the development Authority called the Tennessee Valley Authority (TVA) in 1933. The TVA covered the states, which are drained by the river namely West Virginia, North Carolina, South Carolina, Georgia, Kentucky, Tennessee, Alabama and the TVA also covered the Tennessee’s major tributary, Cumberland.
Steps Taken by TVA to Control Erosion;
1. Constructions of 32 dams were constructed across the main rivers and its principal tributary.
2. Reforestation was done especially on the steep slope of Appalachian Mountain slope.
3. The gullies were filled with brushwood to prep the eroded soil Particles especially silt.
4. Encouraging farmers to use modern and sound agricultural methods Like contour ploughing, terracing, strip-farming, crop rotation and fertilizers and insecticides.
5. Planting of grass or cover crop on the steep slopes so as to combat the Impact of the surface run-off.
Apart from soil conservation and flood control TVA had long term plans of improving the living standards of the people, improving navigation, developing HEP generation Centers and improving the land use along the river basin.
Success of TVA
Remarkable results of TVA include the following:
1. Reliable water availability from the reservoirs for irrigation in the events of droughts, domestic use and industrial development.
2. Improved navigation along the Tennessee Rivers so that it could be used throughout the year.
3. Availability of HEP to many people.
4. Industrial development was encouraged especially as a result of HEP supply.
5. There was creation of many tourist attraction including national parks.
6. Improvement in the fishing industry leading to the increased supply of proteins.
7. It added to another source of income in the country especially foreign currency earnings due to tourism etc.
8. Heavy industries were established like machinery and aluminum melting at Birmingham in Alabama and Atlanta in Georgia. Atomic power station and aluminum smelting at Alcoa.
TVA project in the USA is an outstanding example of how planned programs can be made to work successfully. With sound planning, careful resource management and human cooperation, men can overcome the `most hostile environment or rehabilitate a devastated region. If this kind of project could be done in the underdeveloped countries of the world many of the poor could be better-fed and hipper human beings.
The positive results in soil conservation were due to:
1. Financial position of the country hence it could be easily to invest in the conservation programs.
2. Good and advanced technology used in the conservation process.
3. People’s readiness to accept some advice and changes.
4. Strong cooperation among the people.
5. Close government involvement.
SOIL CONSERVATION IN TANZANIA
Tanzania has also been experiencing the problem of soil erosion in many parts .This has been affecting agriculture in a negative way through the loss of fertility and the reduction in the size of arable land. Poor cultivation methods on the slopes, overgrazing in some places, deforestation because of cutting trees and over cultivation are some of the causes which have been responsible in the occurrence of soil erosion in different parts of Tanzania. The problem of population pressure in some places has been so instrumental in the facilitating deforestation and land fragmentation.
Soil Erosion and Conservation in Kondoa (Tanzania)
Kondoa is the one of the areas, which has been affected by severe soil erosion. It was caused by:
1. Unstable soil due to semi aridity.
2. Sporadic heavy rains that tend to wash away the loose of soil materials.
3. High population in the area led to the destruction of vegetation.
4. Hilly landscape on which water runs fast.
5. High animal population that led to overgrazing.
There are different strategies, which have been used in Tanzania so as to Curb this problem both at an individual level, village level, regional level and National level. Some of the strategies are:
1. Contour ridging on the slopes of the highland and hills. This is practiced widely in Rukwa , Tabora , some parts in Mbeya (Mbozi and Rungwe) and Iringa.
2. Using farm yard manure to restore fertility. The use of farm yard manure is common among the Sukuma, Ukara-Ukerewe and Sumbawanga Where people collect cow dung from the grazing areas or cattle sheds.
3. Fallowing is also practiced whereby people leave the land uncultivated for sometime especially after exhaustion so as to regain its fertility.
4. Resettlement scheme or villagization programs were introduced with the aim of improving the land use and stop shifting cultivation, which is a poor method and detrimental to the environment.
5. Encouraging crop rotation so as to stabilize the soil.
6. Planting drought resistant crops in the widely cleared dry lands.
7. The use of leguminous plants like sun hemp (marine) and cultivation of groundnuts as well as beans so as to maintain fertility. sun hemps are used in Ruvuma (in Namanjule villages), Dodoma ,Mbulu ,Tanga ,Rukwa ,Iringa , Songea, Mbeya Especially in Mbozi and Kigoma sun hemp is used as a weed killer ,insecticide and fertilizer and was brought by the Tanzania government from Indian in 1942,sun hemps are highly recommended as a cheap and easy technique of maintaining fertility.
8. The use of Ngoro farming system in Umatengo (Mbinga) District in the southern part of Tanzania. In this system the crop are planted on the ridges and all the waste matter is thrown into the pit so as to get rotten future use as manure.
9. Inter cropping in which perennial crops are combine with food crops. The perennial crops add up fertility through shedding the leaves. Inter cropping help in stabilizing the soil hence checking soil erosion .For example in Moshi people are inter cropping beans or maize with coffee and bananas.
10.Restocking has been encouraged coupled with the introduction of Modern and proved breeds. In many areas many farmers are practicing Mixed farming at a small scale and zero grazing (indoor rearing ). This Reduced pressure on land has given room for the improvement of soil quality. E.g. Mixed farming is now being practiced in Mbeya, Moshi and few areas in Iringa and Sumbawanga. Commercial ranching has been established for proper management of both animals and pastureland. Rotational grazing in paddocks is being practiced so as to avoid causing land degradation.
11.Afforestation programs like HADO ‘Hifadhi Ardhi Dodoma” were Introduced in which the trees were planted to prevent soil erosion and combat the drought conditions.
In 1967/1968 financial years the government instituted village afforestation programmers as a means of alleviating both fuel, wood scarcity and reserving soil degradation problem. Mbeya also responded to the programs and began planting trees. In 1980 the institute of Adult Education in conjunction with the Ministry of Natural Resources and Tourism and the Ministry of Education and Culture instituted intensive educational campaign on village afforestration and reforestation. Also books titled “MISITU NI MALI” (Forest are Wealth) were published and set posters on the theme of deforestation and desertification have been produced. Likewise the government has declared other areas as forest reserves e.g. in Mbeya the forest reserves cover about 422,000 hectares (about 75% of the total areas of the region).
12. Mulching is also used to prevent erosion and excessive evaporation when the grass decays it adds to the soil fertility.
13. Terracing is also used in some areas associated with planting of grass, which provides a uniform cover, and reduces the speed of the running water down the slope.
14. There are some programs for educating people both in schools and in adult classes such programs are also disseminated on the radio, through newspaper, printing on the vests and matchboxes which carry information that encourage environmental conservation.
15. Introduction of irrigation schemes in some places like in Usangu, Dodoma, Kilombero and Nyumba ya Mungu etc.
Drawbacks Hindering Soil Conservation in Tanzania
1. Financial problems due to poverty among the farmers they therefore can’t invest in the modern programs of oil conservation.
2. Low commitment among the members of the local government and individuals reforestation programs. The National tree planting Campaign that was stated in 1999 has not yet realized good progress so far.
The problem associated with the tree planting campaign is that the trees, which were planted, were not carried for they were forgotten and literally abandoned to die; thereby sabotaging the conservation campaign. Also there was no specific organ given the task of supervising the planting and caring processes. Nonetheless, the government leaders are still stressing on the necessity of planting more and more trees so as to conserve our environment. Those who have planted should take care of them so that those which have been planted can grow and survive into full maturity.
3. Lack of effective and efficient coordination of the soil conservation activities both at a local level and at a national level.
4. Rapid population increase creating pressure on the land and its resources the land is cheap resource; any need for excessive population (like food) is met by exploiting land resources especially through agricultural activities.
5. Most of necessary information is confined in urban areas and people in rural areas are not yet reached due to transport problems.
6. Political problems siphon a lot of money in the process of solving them. So most money is directed to these problems rather than solving environmental problems, which use extravagant amount of money that could helping soil conservation.
7. There low international support.
Problems of Agriculture in Tanzania:
1. Soil erosion: This destroys the land in many parts of Tanzania especially increase like Usambara, pare and Kondoa–Iringa areas.
2. Unreliable and poorly distributed rainfall: sometimes there long droughts leading to crop failure while at times it is too much leading to flood is unevenly distributed due to relief, wind and the over head sun.
3. Temperature, diseases and pests: The tropical climate encourages the trivial of diseases and pests, which harm people, crops and animals in the farms. For example fungal diseases, bacterial diseases and malaria are a rampant problem in Tanzania. Pests include army worms, quell, locusts, and grasshoppers and stalk borers. Animals like monkeys and pigs attack crops in the farms.
4. Too seasonal rivers: There is a big problem with rivers such that sometimes they go dry leading to problems of water availability in the irrigation schemes. Dams are not constructed due to the lack of capital.
5. Land shortage: In some places due to overpopulation like in the Chagga land and Umatengo etc, some people are landless. In those areas land is highly fragmented and hence mechanization is difficult. Apart from overpopulation other areas are swampy mountainous have mining pits, etc leading to problems in cultivation.
6. Poor knowledge and low technology: Most of the farmers use poor farming methods due to poor knowledge and low technology. In some places the farmers are illiterate and hence they cannot learn new methods of farming easily since they are still conservation and adamant to accept new and positive changes.
7. Poor marketing system: The internal market is poor due to low purchasing power among them is bought on credit without being paid early. The international market is also poor due to price fluctuation. Sometimes the prices are very low discouraging the farmers to a great extent.
8. Gender discrimination and inequality: Women are the ones who are involved more in agricultural products and land. They are not involved in the decision making process, they are not well trained and do not own land because of poor cultural traditions. This contributes to the decline of agricultural production in Tanzania.
9. Poor transport and communication: Some areas are like Rukwa, which is one of the granaries of Tanzania, experience great problems of transport and communication. Hence, ferrying of agricultural products, disseminating information on new agricultural techniques and distributing important services that support agriculture become difficult. The villages in these areas are badly hit by this problem. For example in 1980’s a lot of crops got rotten in Rukwa due to poor transport at the same time some people in Shinyanga were starving because of shortage of food supply.
10. Poor storage facilities: Most of the farmers in rural areas do not have good storage facilities such that they cannot store properly their produce. Most of the agricultural products go bad leading to great losses.
11 Too much selectivity: Some communities are used to certain type of food crop and are not ready to switch to another type of crop. Such that once that crop fails they get problems of hunger while they could as well grow another crop that could serve the same purpose. For example some people in Rukwa are used to maize and hence they find it difficult to grow cassava during the drought period. Hence they end up getting problems of food supply.
12 Agricultural policies: They have not been so emphatic on agriculture due to the diversification of priorities. Unlike in the USA and China, the policies have been so soft such that agricultural development has been dwindling time from time in the rural areas. This has led to food shortage such that Tanzania has been importing some food from outside despite having great potentials for producing adequate amount of food.
13. Rural- urban migration: People especially the young ones, are so mobile moving from rural to urban areas Rural–urban migration has negatively affected agriculture in Tanzania. Many young people are living in the village and flood the towns leaving the rural areas with young children and the old people who cannot effectively and efficiently engage themselves into agriculture.
What should be done?
1.There should be comprehensive schemes for undertaking soil conservation by the methods like crop rotation ,controlled grazing, contour, farming, dry farming (mulching), terracing and strip cropping as well as facilitating the processes of restocking ,afforestation and reforestation.
2. Educating people both in the school system and out of school (formal and non –formal education) on how to apply sustainable method of cultivating.
3. There should be high disease and pests control by cleaning the thickets, draining water, from the ponds and marchers, spraying the crops with chemicals, improving health care centers and developing researches on different disease etc.
4. Introduction of irrigation schemes. Hence reservoirs or dams should be constructed to ensure constant supply of water in the farms, such attempts have been made in Tanzania like the Nyumba ya Mungu dam, Mtera dam, Mindu dam in Morogoro etc.
5. Construction of better roads, good storage facilities etc. International linkages should be improved so as to facilitate the diffusion of new technology to our country.
6. Land reallocation and resettlement schemes should be reviewed, for example during vulgarization there were problems of sending some people to which were not fertile. Hence, before establishing a settlement anywhere, there should be profound preliminary surveys so as to assess land suitability for settlement.
7. Rural-Urban migration should be reversed. This can easily be done through investing in the rural areas. Great economic projects should be launched in the villages so as to promote the living standard of the people in rural areas and make people stay instead of moving to towns. Once rural areas are more developed some urban dwellers can be attracted to rural areas.
8.There should be improvement in the marketing system. Internal market can be improved through the development of cooperative boards the way it was with NMC, establishing local industries that are agricultural oriented like textile industries and food processing industries. Good price should be set and the payments should be done immediately. External market can be improved by trading with other countries with high quality crop products, uniting to promote bargaining power in the world market, diversification in the world market etc.
9. Another measure of improving agriculture is by empowering women so that they can also have more rights and greater room for participating in giving their own views on the way of improving agriculture .Women should also be given land to own in order that they can take of it and hence produce effectively. Men also should be actively involved in the agricultural activities so that the great burden or work low that women are having can be reduced.
10.Maintaining peace in the country so that people can settle and concentrate on production rather than keep on the fleeing as, refugees to other countries. Peace can make people engage effectively in agriculture since they will be feeling secure but when there are conflicts a lot of time and resources are wasted in wars and famine becomes a common factor dominating the country’s course of life.
11.Comprehensive guidance and counseling programs should be launched in order to educate, especially the young people on the dangers of the killer disease HIV/AIDS which is claiming the lives of a large number of young and energetic producers. These programs should be organized by both government and non-governmental institutions as well–willing individuals so as to effectively make concerted efforts in combating this disease. In many parts of the country HIV/ AIDS has led to the problem labor shortage as a result of the death of the young people.
1. Write short notes on the following terms.
c) Beef farming.
d) Dairy farming.
2. What are the factors hindering the development of ranches in Tanzania?
3. Identify the advantage and disadvantage of ranching in Argentina and USA.
4. Outline the factors that have lead to the development of beef farming In Argentina.
5. Show the role of sheep farming to the economy of South Africa
(Show its advantage).
6. Why is beef farming more developed in the temperate areas than in Tropical area?
7. Identify the measures that can be used in combating the problems facing large scale farming in East Africa.
8. How does the rapid population growth affect livestock farming in Africa?
9. Show the effects of livestock farming on the environment.
10.Why mixed farming is more developed in the USA Corn Belt than In Tanzania?
11. Mention the tribes involved in the following agricultural systems.
a) Shifting Cultivation in West Africa..
b) Nomadism in East Africa.
c) Semi-nomadism in Tanzania and Uganda.
12. Mention the examples of the countries where the following
Agricultural systems take place.
13. Mention the factors that influence agricultural development in any country.
14. How is nomadic pastoralist carried on and organized?
Support a wide range of light and heavy industries around changing (Chunking) and Chengdu (Chengtu). Lesser deposits occur in the province of Yunnan, Guizhou(Kweishow), Jiangxi (Kiangsi) and human- serving local demand only.
Factors, Which Have Facilitated the Use of Coal as a Source of Energy in China
1. The presence of large deposition of coal almost in all provinces.
2. The presence of heavy industries, which need great amount of power to run effectively. These industries have provided market for coal.
3. The use of mechanized methods in the extraction methods due to the advanced level of technology in China.
4. The presence of well-developed transport system especially the railway system has facilitated the distribution of coal.
5. Easy accessibility of some place like Manchuria has also facilitated the extraction of coal deposits and hence high use of coal in china.
6. Depth of coal deposits has been another factor. In some places like Fusion and fixing cheap open-cast methods are used in the extraction of coal. since the deposits lie the surface.
7. Labor availability due to high population in china .Labor has not been a big problem in the mining of the coal.
Importance of Coal Mining in China
1.It has stimulated the development of industries in the countries in the Heilungkiang province. Heilungkiang heavy industries make steel, machinery ,cars, tractors, etc, This has been possible since Manchurian Coal seams are thick, easily accessible and are having some high- grade coking coal.
2. It has provided employment to many people in the country reducing the problem of unemployment in such most population country in the world.
3. It has contributed to the generation of the government revenue and creation of capital to be invested for further economic development in the country.
4. Coal mining has stimulated the development of transport and communication systems like railway lines, roads etc. There are car industries, shipbuilding industries and other transport- oriented industries, which have developed as a result of the impact of coal mining.
5. It enhanced the development of mechanized agriculture through the promotion of heavy industries .Heavy industries have been produced some farm machinery like tractors and combine harvesters. This has enabled China to feed its high population.
6. It has also contributed to the improvement of the living standard among the people. This has been a result of the improvement in the supply of social service like education, medical treatment, power etc.
Problems Encountered in the Extraction of Coal in China
1. In some places the deposits are becoming deeper and deeper leading to the rising of a expenses of coal extraction.
2. Some coals seams in some places like Mongolia are folded or faulted creating problems in the extraction.
3. Some deposits are so scattered like in the Sichuan coal fields.
4. Coal is an unclear source of energy that creates some health problems when extracting.
5. There is a stiff challenges posed by other countries like the USA and Russia, which also procure coal.
6. Opposition from the environmentalists who are discouraging the use of coal as source of energy and like salary energy, wind power etc.
7. Exhaustion of coal deposits in some places contributes to the decline in total production of coal in the country.
EXTRACTION OF COAL IN THE USA
The USA is the world’s leading producer of coal and her major coalfields include the following:
1. The Eastern region (Appalachian fields ) which is the most productive region .The area produces about 70%of all USA coal . The coalfields include Pennsylvania field producing anthracite and coking West Virginia coalfield, which produces steam, coal and household, coal and Alabama coal fields which are minor deposit.
2.Interior region (central coal fields) is the second major producer of coal in the USA producing mainly bituminous coal. It extends from Lake Huron, Indiana, Illinois, low, Missouri Kansa, Oklahoma and Arkansas. Coal produced in this region serves large market in the Great lakes shore lands, Middle West and other industrial district in the region. This region contains USA major conurbation of Pittsburg.
3.Gulf region which include the states of Texas, Alabama, and Arkansas. Hence lignite coal is found in scattered deposits.
4.The rocky mountain region. This has the greatest American coal reserve but has not been exploited much because of its inaccessibility and distance from the markets. Coal produced in this region is mainly of lignite and low- grade bituminous types.
5.The pacific region has small coal deposits that are of limited local importance .The fields are Oregon, California and Alaska as a reserve for future supply.
The methods used in the extraction of coal in USA include simple stripping (open cast) method like in the western interior where the seams are horizontal and near the surface ,shaft method in some parts of Appalachian field where the seams are deep situated and audit (Hill slope boring) method where the seams are exposed on the valley side
Factors that have facilitated Coal in the USA
1. Availability of coal deposits, some of which are very large, of high quality and easy to work.
2. The use of mechanized methods in the extraction of coal from the ground.
3. The presence of large iron deposits required for metallurgical industries demanded great amount of power, which was then to be obtained from coal.
4. Well –advanced transport system, which made accessibility easy, and transportation of coal effectively done.
5. Strong support by the government, which was eager to enhance the supply of power so as to hasten the pace of industrial development in the country.
6. Availability of both capital land labor made the coal mining process develop at a high speed.
Importance of Coal in the USA
1. It has stimulated the development of iron and steel industry in Birmingham and Pittsburg district( the iron and steel capital of the world), pharmaceutical industries and the making of locomotives.
2. It has led to the creation of employment opportunities for many people of USA.
3.Transport and communication systems have developed fast in the country due to the supply of power. There has been development of locomotives, which play a great role in the transportation system.
4. It has led to the creation of capital that has been invested in other sectors like agriculture, tourism.
Limitations of Coal Mining in the USA:-
1. Problems in mining where there are faulted and contorted seams especially in the North, Eastern Appalachian coal fields despite having an excellent anthracite coal.
2. Some deposits are small, scattered containing low-grade coal like the Pacific region.
3. Inaccessibility of some places like the Rocky mountain coalfield due to the difficult terrain, and distance from the market. The Rocky mountain region has the greatest reserve but the coal is of low grade.
4. Other sources of energy like Nuclear power, Solar power, Wind energy, HEP are posing a stiff challenge or competition to coal. For example the presence of oilfields in the interior provinces has negatively affected coal production.
5. Coal is a non – renewable resource hence it has been getting exhausted due to exploitation.
COAL EXTRACTION IN SOUTH AFRICA
South Africa has coal deposits and is the foremost coal producer in Africa. First coal was mined at Molteno in the Cape Province (1864). In 1879 the revenging was discovered.
Main Producing Areas
1. Transvaal: Is the largest producing approximately 62%. Transvaal Wit bank collieries are the heaviest producers and coal is good (system coal) but rather unsuitable for cooking. Its rapid exploitation is due to its closeness to the rand and ease to extraction. The seams average 60 ft thick and lie close to the surface. Mining is safe due to stable seams with little gas. These factors and low labor costs make the coal mining the cheapest in the world. Other major mining centers in the Transvaal include Verceening, Ermelo, Belfast and Boksburg.
2. The Orange Free State: Coal mining in this region is confined the northern fringe centered around Vierfontein, with small mining zone south – east of Vereeniging where low quality coal goes to the power station near Klersdorp on the veal and the Saxonburg plant for extracting oil from coal.
3. Natal Coalfield: The chief mining centers are Vryheid, Utrecht, Dundee and New Castle. The seams in Natal are thinner and more countries faulted but there is much high-grade cooking and steam coal.
Factors which have Led to the Development of coal mining in South Africa:-
1. The technological advancement that facilitated the exploitation and the mining process. Extensive exploration was done unlike other countries like Tanzania.
2. Low cost labor was readily available especially from the neighboring countries like Mozambique and Malawi who went there as migrant laborers.
3. Ease of mining because of the deposits lying close to the surface.
4. Good transport and Communication system in the mining areas has facilitated the development of coal mining in South Africa.
5. Closeness of the coal deposits to the industries areas stimulated the development of coal mining since no much costs were involved in the transportation coal.
6. The strong need for oil fuel has made South Africa produce a lot of coal for the sake of extracting oil. It does not have oil deposits therefore it extracts oil from coal at Sasolburg; Sasolburg uses 60% of coal for producing oil.
7. Large seams of coal in South Africa give confidence of the continued coal mining in the country. This aspect has encouraged the investment in the coal mining.
8. The government of South Africa has been putting much emphasis on mining and hence a lot of great investments were made on mining and hence a lot of great investments were made on mining and these covered coal mining.
9. Large external demand from Europe and elsewhere also stimulated the Development of coal mining in South Africa.
Importance of coal mining in South Africa
1. It has highly stimulated the development of transport systems in the country ranging from roads, railway lines etc.
2. There has been fast development of different types of industries in the country because of providing power. For example cooking coal has stimulated the development of iron and steel industries in Vereeniging, Durban, new Castle, Pretoria and Johannesburg. These are locomotive industries which have developed because of the influence of coal production.
3. Coal mining has also contributed to air pollution by introducing green house gases like carbon dioxide and carbon monoxide as well as water pollution.
4. Health deterioration among the workers since coal is a dirty energy resource.
5. It has also contributed to the labor shortage in Malawi and Mozambique because of labor migrants from these countries to the coal mining areas in South Africa.
Limitations facing coal Mining in South Africa.
1. Rising coasts of mining due to the aging of machines and deepening of mines.
2. The problem of coal exhaustion as a result of over dependence on coal as the source of energy. For example coal is used for fuel oil extraction. This has encouraged an over exploitation of coal in South Africa.
3. There are stiff challenges posed from other environmentally friendly and sustainable resources like solar energy, water, wind, power, as well as the upcoming challenge from the increased use of nuclear energy, which is more economical and clean compared to coal Nuclear energy is produced from Uranium in South Africa.
4. Despite the abolition of the apartheid system, there some occasional conflicts, which occur between Africans and the bores creating, labor unrest.
5. Water problem is another hindrance. This is because of the fact that large part of South Africa does not get heavy rains and the rivers are short running away from the interior part of the country to the oceans. Hence, water shortage is experienced and that which is available is under high competition from mining section, agriculture and manufacturing industry.
6. Labor competition with other mining sectors as well as industries. Other mining sectors like gold mining, diamond mining, etc are regarded as more precious and hence more paying than coal. Therefore, more people go to those mining areas leaving the coal-mining sector suffering from labor drain.
7. Another limitation factor is food shortage since the arable land is small and many people are concentrating on the mining activity and manufacturing industries.
8. Staunch opposition from the environmentalists, who are diligently advocating for the use of environmentally friendly energy sources rather than coal, which is harmful to the environment.
COAL IN TANZANIA
Tanzania has large reserves in the South West of the country in the Ruaha basin, the Katewaka – Mchuchuma area and Songwe – Kiwira area.There is active mining taking place in Songwe – Kiwira to supply coal to the cement industry in Songwe. The reserves at the Ruhuhu basin and the Katewaka – Mchuchuma areas are estimated at over 500 million tons of recoverable high quality coal. According to a specialist on ecological engineering at the University of Dar es Salaam, Dr. Mkilaha, researches show to those found in South Africa and Australia. (Business Times 22/2/2002, page 3). Dr. Kilaha said Tanzanian coal is suitable for domestic use, manufacturing industries, and power generation.
Mchuchuma – Katewaka is the leading coalfield in Tanzania. It is has the coal that coal generate about 400MW using Circulating Fluidized Bed Combustion (CFB) technology that has been proposed to take off. Experiments are being conducted to determine if Tanzanian coal can be mixed with biomass to produce less pollutant substances. This will involve mixing the coal with biomass in boilers so as to reduce such pollutants like Nitrogen Oxides, which are culprits for the acidic rain to be over 20 million tons. In this zone lies the future potential for development of heavy industry in East Africa.
The National Development Corporation (NDC) has established the project proposal for establishing the thermal plant 287 kilometres from Makambako town envisaged to consume about 1.38 million tons of coal annually (Business Times 22/2/2002, page 3). It is estimated to cost US$ 660 million and generate 400 Megawatts from burned coal. The heat energy would then be converted into electric energy. NDC experts that the first unit of the plant will be accomplished in 2004, to implement the project the NDC plants to involve the private sector. In the plan, it is proposed to create a private power subsidiary owned by NDC. This subsidiary will then select an Independent Power Producer of international reputation and experience to be a partner in a joint venture company. Meanwhile the Environmental Impact Assessment done by experts sponsored by the government and the World Bank revealed that the envisaged project for utilization of coal deposits at Mchuchuma Katewaka is viable. The consortium of investors in the Mchuchuma coal project includes Siemens, Grinaker – LTA, Cinergy Global Energy Corporation and the National Development Corporation of Tanzania (NDC).
Importance of Coal in Tanzania
1. It will stimulate the development of iron and steel industry in Liganga where there are iron ore deposits. This will lay a strong base for a large – scale industrialization.
2. It will lead to the creation of employment opportunities and hence solve the problem of unemployment. There are some people who are already employed at Songwe – Kiwira coal mining area.
3. It will further stimulate the development and expansion of the transport systems like roads and the railway lines.
4. Promotion of the supply of energy for home use and local iron smelting industries like SIDO and other industries like Mbeya Cement Industry in Songwe, etc.
5. Some of coal is exported to other countries like Zambia and Congo leading to the earning of foreign currency.
6. It will also contributed to the generation of electric power and reduce the over increasing power demand in the country and outside especially in the neighboring countries like Uganda, DRC, Zambia, Rwanda and Kenya.
The Drawbacks Facing Coal Mining in Tanzania
1. There is inadequate capital to the invested in the coal – mining sector since Tanzania is economically poor.
2. There is low industrial base hence the market for coal is also very low. This discourages heavy investment in this sector.
3. There is poor transport network in the country and the mining sectors are not well served with roads or railways. The present roads and railway lines are not serving to the maximum.
4. Exhaustion and deepening of mines make the work complex and costly hence leading to low coal production.
5. Problem of labour mobility whereby people move from coal producing areas to other economic sectors, which are more paying. Also, labor availability is hit by the problem of diseases like malaria, HIV/AIDS and killings that take place associated with skinning of people so as to get money. Killing and skinning of people has become a big problem of grave concern in Mbeya and the government and its people have to wage concerted efforts so as to stamp out this great problem.
6. Delays by TANESCO in signing the Power purchase Agreement (PPA) with the identified consortium of investors are another hindrance in exploiting coal deposits. The sources said that the delay was due to the uncertainty arising out of management changes in the Company. The contract between the government and the South African firm (Net Group Solutions) held up the start of the project, which was scheduled to start in December 2001 (According to Business Times Friday, May 10- 16, 2002).
It is also a non – renewable resource and was formed underground from decaying animal and plants.
Main producers include Middle East, USA, Russia, Mexico, China, UK, Norway, Canada, Venezuela, Nigeria, Angola, Algeria and Libra.
Origin of Oil (Petroleum)
Petroleum which is in its natural state is called crude oil. It is a compound of hydrogen and carbon. It is thought to have been formed from the decomposition of marine organisms (plants and animals) which collected in the sediments on the floor of some seas. The decomposition was done by anaerobic bacteria. Some scientists believe that the compaction of the deposits lead to the creation of high heat and pressure that transformed the decaying organic matter into oil droplets.
Uses of Petroleum
Petroleum (oil) has a wide range of uses in industries, commercial centers, agriculture, etc.
It is used as follows:
1. It is used as fuel to provide power in the machines in the industries or car engines.
2. It is used as lubricant to reduce friction in the cars, bicycles etc.
3. For heating, cooking and lighting.
4. For manufacturing petrochemicals for making synthetic textile, dye stuffs, fertilizers, insecticides, resins, adhesives, detergents, plastic materials, medicine, etc.
5. Other uses include making of tar for roofing and road construction, candles, Vaseline.
6. It is used for generating electricity, producing petroleum gas.
Methods of Extraction
Oil is extracted through drilling and there are two ways of drilling. These include percussion or cable- tool method and the rotary drilling method. The percussion method was used by earlier drillers like Edwin Drake in drilling shallow wells of not more than 610 meters. It is cheap but slow and inefficient.
The Rotary drilling method is the modern method used by companies and is more efficient. When the oil – bearing rocks have been located, a hole is drilled from the surface to the rock containing oil. This is done by means of a large metal structure called Derrick. From the derrick a steel pipe (shaft), which is fitted with a drill head called bit is forced slowly into the surface rocks. When the oil deposits are reached the oil gushes out under natural pressure or pumped out. Then it is transported to the required places by pipelines or tankers.
Manufacturing involves three basic operations:
1. Fractional distillation. Breakdown of hydrocarbon mixture into different parts. Then the crude oil is vaporized and allowed to condense in a distillation column. This leads to the production of liquid fractions as follows;
(a) Natural gas, Petroleum gases and gasoline (gasoline is used for internal engine combustion).
(b) Kerosene (Mainly used as fuel for jet aircraft).
(c) Gas oil (Is made into diesel for powering and locomotives).
(d) Residue of heavy oils, which when distilled in vacuum produces lubricating oils, wax and bitumen, Bitumen is used for making roads and roofing.
2. Conversion of hydrocarbons from one fraction in a vacuum. The fractions are heated under high pressure to get lighter factions which are of high demand.
3. Purification of the fractions to remove various impurities especially sulphur compounds.
1. Low receives, which tend to inadequate energy supply exhaust of oil deposits.
2. It leads to air pollution, which is turn causes harmful effects to man and other organisms. For example the burning of fuel oil leads to the emission of green house gases like carbon dioxide and carbon dioxide and carbon monoxide that contribute to the occurrence of the global warming phenomenon.
3. The oil spills are dangerous to the ecosystems. When oil forms the uniform cover on the surface of water, it prevents the diffusion of exigent leading to the death of living organisms like fish, valuable plants, etc.
4. It leads to accidents due to fire outbreak and exploitations.
5. It needs high capital in establishing. Hence, poor countries like Tanzania cannot be able to easily establish the oil mining industry because of low or lack of capital.
OIL MINING IN AFRICA
Today’s Africa’s major oil producers include Nigeria, Libya and Algeria which range among the top fourteen producers in the world. These three countries together with Gabon are the members of O.P.E.C. Other producers of oil in Africa include Egypt, Angola, Tunisia, Congo and the Democratic Republic of Congo.
Oil Extraction in Nigeria
Nigeria is the tropical Africa’s largest producer and exporter of Petroleum (oil). Oil mining in Nigeria began in 1937 but it was not until 1956 that commercial deposits were discovered and production began in 1958 at the Otoibire Field. The companies that stated oil mining in Nigeria includes Shelf B.P (British Petroleum), Gulf, Mobil, Texaco, and Safrap. In 1971, the Nigeria National oil Corporation was established.
Oil Producing Areas in Nigeria
Major oil fields are found in the Niger delta area (along the coast) and in the offshore zone. There are also good prospects of locating other oil fields within Nigeria. It is believed that there are many potential deposits along the coast especially the continental shelf off Nigeria’s coastline. There are large refineries at Port Harcourt and Warri near the oil fields. The other refinery at Kaduna is linked by pipeline from Warri. At Afam there is a large gas – field.
Factors for Oil Mining Development in Nigeria
1. Presence of deposits which are large and cheap to operate.
2. Labor availability since Nigeria has the largest population in Africa.
3. The government support on the development of oil mining industry.
4. The role of the foreign companies, which had enough capital to start mining.
5. Easy transport since the deposits is located along the coast where exportation has become very easy.
6. Development of transport and communication system stimulated the industry. There are roads and railway lines as well as pipelines for transporting crude i.e the net work of pipelines linking the oilfields and the oil terminals at Warri and Bonny was another for export.
7. Strong need to diversify the economy of Nigeria was another factor, rather than depending on agricultural products especially palm oil production.
Importance of Oil in Nigeria
1. It has created a large number of employment opportunities for the population, which is the largest in Africa.
2. It has led to the development of thermal production centers.
3. There have been earnings of foreign exchange. Oil sector today accounts for most of the country’s foreign exchange. Oil contributes more than 90% in the foreign exchange.
4. It has stimulated the development of transport and communication.
5. The oil industry has reduced a lot the importation of oil, although the country still has this problem because of exporting too much of what is produces.
6. It was earned Nigeria world repute as one of the major oil producing countries in the world.
7. It has encouraged the development of other sectors like social services supply, development of industries.
8. It has led to the development of towns and ports.
9. It contributes about 41% of the national income.
10. It has reduced over-dependency of loans and grants from outside.
11. It has made Nigeria invest in the development of science and technology so as to cope with the current rhythm of life system in the world.
Problems of Oil Mining in Nigeria
1. It faces a big problem of labor unrest due to civil wars, which are still taking place.
2. Deep mining has become expensive since it needs sophisticated machines.
3. Oil mining has contributed to water pollution.
4. Extraction tends to be difficult where the hard rock cover the oil bearing layers.
5. Development of new oil well cause land degradation especially along the continental shelf.
6. It is threatened by exhaustion due to intensive extraction of oil.
7. The companies prospecting oil are foreign owned by Japan, Italy, USA, Britain, and Germany. Only few are owned by Nigeria.
8. Shortage of capital to explore more deposits.
9. Price fluctuation in the world. It can be fall or rise and the market is under high competition.
PETROLEUM IN TANZANIA
The economy of Tanzania is much more heavily dependent on petroleum than any other source of energy. Tanzania imports petroleum from other countries. Hence, importation affects the economy of the country because of fluctuation in supply, demand and prices. To facilitate the supply and distribution of oil in Tanzania there are zonal depots constructed to supply petroleum products. Mbeya for example receives oil from Mikumi depot, which also supplies Iringa, Ruvuma and Rukwa. The government has also allowed the private companies like OIL COM, GAPCO, PB, TOTAL, ENGEN, ORYX and KOBIL to supply oil to the people in the country so as to facilitate the distribution of energy in the country. These in an oil refining plant TIPER situated in Dar es Salaam. But overhauling of the refinery and aging of the machinery has been leading to the decline in capacity. TIPER refinery plant has been producing 62% of the equipments of Tanzania for refined petroleum products. Remaining 38% of the country’s requirements are imported.
Export of Petroleum
Tanzania exports limited quantities of refined oil to neighboring countries like Rwanda, Burundi, Zambia, and Democratic Republic of Congo (Republique Democratic De Congo).
Importance of Oil in Tanzania
1. Provision of employment opportunities at TIPER and the companies like GAPCO, OIL COM, and ENGIN, etc.
2. It contributes to the generation of the government revenue that control the prices of oil.
3. It has encouraged the development of industries in the country.
4. It has greatly stimulated the development of the transport and communication systems in the country.
5. Other sectors like tourism and trade have expanded to a greater extent as a result of the use of oil as a source of energy especially in the transport and communication network.
6. Improvement in the living standard of the people due to the increased supply of energy in the homesteads.
Problems Associated with Petroleum in Tanzania
1.The data on energy flow and use in Tanzania is not adequately available since some companies are reluctant to release data and keep it as business secret.
2.Soaring prices on the importation of both crude and refined oil. This has made Tanzania to be strict on the nature of use of oil especially in the government sector. To solve this problem there have been several explorations conducted by the government to see whether there can be deposits within the country so that production can start taking place within the country. Some tests conducted in 1979 confirmed of the possibilities of petroleum presence at Songosongo associated with natural gas.
3.Transport problems like poor roads leading to delays and accidents on the way as well as high transport charges lead to the problem of oil supply.
4.Other problems like leaking of oil containers and oil pipes, fire out break lead to the problems of oil availability in the country.
5. Due to aging of the refinery plant at TIPER the refining has declined from 810,000 tons and probably to below 750,000 or below 680,000 tonnes per annum.
6. Civil wars in the neighboring countries like Burundi and Rwanda have been deterring exportation of oil to those countries.
7. Low level of technology that has led to poor exploitation of oil deposits in Tanzania.
8. Lack of capital to be invested in the exploitation activities and establishment of oil plants.
Prospects of Oil Extraction in Tanzania
It is expected that once full exploitation going on at Songo songo gas deposits. There is a possibility of getting oil since the researches show that there are all signs of oil deposits associated with natural gas at Songo songo. More exploitation is going on in the Rufiji Basin with the aim of discovering both natural gas and oil. The prospects are so far ‘good.
OIL EXTRACTION IN THE MIDDLE EAST
Middle East produces about 35% (over 1/3) of the world’s annual production of petroleum and most of this comes from the area around and beneath the Persian Gulf. The three leading producers of the Middle East Iran (31%), Saudi Arabia (28%), Kuwait (18%) followed by Iraq (10%). Proven reserves in the region amount to more than ½ of the world are total.
About 1/3 of the Middle East Oil production is refined in the Middle East at centers like Abadan and Kirkuk. The rest is exported in the crude form mainly to the Western Europe, Japan and Canada. Regarding the world production Middle East is by the largest followed by North America (25%), the former USSR (15%), Africa (10%) and the rest (7%).
At the beginning most of the Middle Eastern countries experienced the problems of technological backwardness, small population and lack of capital. Hence, the international companies have largely been responsible for exploiting these oil reserves. Almost all the oil from the Middle East countries is exported. The major pipelines run from the inland fields on the Persian Gulf to the Mediterranean Coast.
Impact of Oil in Middle East;
1. It has encouraged the development of industries in the countries.
2. Oil has led to the rise in per capital income among the individuals.
3. Has led to the rise in the amount of export e.g. Kuwait 100%, Saudi Arabia 99%, Iran 85%, and Iraq 90%.
4. The revenue from oil production has enabled Middle East to develop their cities with great economic and social status.The health services and education improved tremendously.
5. Various Sheikhs and rulers were able to build luxurious palaces and ultra – modern apartments.
6. It has become possible for the countries to invest overseas leading to the addition of another source of wealth to the Middle East States.
Oil production in the Middle East is often subject to disruptions. Conflicts between the Arabs and Israelis, the undefined nature of many of the desert boundaries, and the conflict between rival sheikhdom or rival governments, as in the case of Iraq – Iran war of the 1980’s, then the Gulf War of 1991 and war against Terrorism waged by Americans (from 2001) make oil industry in the Middle East countries insecure.
It is a non-renewable resource. It is formed underground from decaying animal/plant materials. The main producers are USA, Canada, Russia, Mexico, Venezuela, Algeria and China. Tanzania has discovered the natural gas deposits at Songosongo in Kilwa. It is used for cooking, heating and production of electricity.
Advantages of Natural Gas
1. It is an efficient source of energy.
2. It is clean – least polluting of the fossil fuels.
3. It is easy to transport.
1. It explodes easy leading to destruction and death.
2. It causes some air pollution.
3. It is exhaustible (non renewable source of energy). Oil, coal and natural gas are referred to as thermal (fossil) energy sources.
GAS PRODUCTION AT SONGOSONGO TANZANIA
In Tanzania Natural gas deposits have been discovered at Songosongo (Kilwa – Lindi region) about 200 km south of Dar es Salaam. Songosongo deposits are capable of providing about 8% of the world production of commercial gas when full production starts. Its life span is natural gas at Songosongo was discovered in 1974 by the Tanzania. Petroleum Development Corporation (TPDC). Two wells were sunk in the area and showed proven reserve of natural gas of about 2.8 billion cubic meters. Subsequent tests conducted in 1979 confirmed the possibilities of an oil accumulation together with gas. The project is started to cost about 320 million US dollars and will generate 112 MW of electricity. The AES Corporation based in Airling ton, Virginia in the USA, is currently the major investor in the project and has a US$ 50million equity investment in the joint venture. The other shareholders in the project Son Gas Limited – are CDC Financial Services, the Tanzania Development Finance Company (TDFL), Tanzania Electric Supply Company (TANESCO) and Tanzania Petroleum Development Corporation (TPDC). The project produces gases that will, among other uses, be used generate electricity at the Ubungo power plant.
The project involved the development of one trillion cubic feet of natural gas reserves at Songosongo Island on the snore south of Dar es Salaam and gas gathering and processing systems at Songosongo. A 25 km land pipeline to Dar es Salaam, also was constructed. The gas is transported to the Ubungo thermal power plant, which was formerly being operated on expensive imported fuel. The turbines had to be converted to go – firing.
The Completion of the Songosongo Gas Project
It was scheduled that the completion of the projection should be by October 2003 but some analysts say that the prevailing situation of slowness and costs delayed the completion as scheduled and this added to costs.
But full exploitation could not taken place quickly because of the following factors:
1.There is low technology among the Tanzanians that can be used in exploiting natural gas at Songosongo Island along the coast of the Indian Ocean. Hence, there is too much dependence on the foreign experts than the local experts.
2.Several ministerial changes in the government and the long disputes involving TANESCO and IPTL also contribute to the hitches (delays) in the project.
3.Low capital to be invested in establishing some plants since Tanzania is one of the poor countries. The project needs high capital for establishing the plant and both sub-marine and land pipelines. These make the project become costly leading to delays.
4. Poor transport infrastructure also compilable the full exploitation of natural gas at Songosongo.
5.The use of other available sources of energy like HEP and forest has delayed full extraction natural gas since some of them are cheaper than gas. It is said that the natural gas might be more expensive than the imported fuel due to the high cost of the project.
Advantages of Extraction of Gas from Songosongo
1. It will lead to the reduction of over dependence on gas from outside.
2. It will stimulate the development of some iron and steel industries by using the available iron deposits in Tanzania as well as scrape iron materials. This will be because of the energy that will be produced from gas resources extracted from Songosongo.
3. It will contribute to the promotion of environmental conservation since natural gas is clean and environmentally – friendly.
4. It will lead to the creation of employment opportunities in the country so as to solve the problem of unemployment.
5. The standard of living among the people will rise due to the provision of efficient energy source.
6. It can stimulate exploitation of other resources like petroleum, which is expected to be present at Songosongo.
7. It will lead to the increased generation of electricity.
8. Exploitation of natural gas at Songosongo might stimulate the extraction of petroleum that has been tested to be present, associated with the natural gas. Exploration is continuing in the Rufiji basin and the prospects of finding more gas and oil are described as “Good and promising.”
Problems that will be caused by the Project
1. It will lead to the eviction of the people in areas where the land pipeline will pass from Songosongo to Dar es Salaam.
2. If importation of fuel from outside will be reduced then people are likely to incur a lot costs in energy supply. This might happen in case the use of the energy source from Son Gas Project will be associated with high costs. The costs are likely to be high due to the high cost of the project. The discovery of Songosongo gas was initially expected to bail out local industries high price of imported fuel and petrochemicals. However, considering the high cost of the project, the gas is estimated to be sold at such a high price that local industries will find imported fuel a cheaper alternative. (Business Times, 22 – 28, Feb 2002, page 2)
Source: Tanzania Petroleum Development Corporation Date: 1 January 2000 Tanzania has been intermittently explored over the last 40 years. Most of the multinational petroleum companies were represented, in the area; at one time or another. Significant gas discoveries were made at Songo Songo and Mnazi Bay. Between 1954- 1997, 25 new field wildcats (NFW) and eight delineation wells (at Songo Songo) were drilled. Of the 25 exploratory wells, 23 were drilled in the coastal basins and two in interior rift Rukwa Basin. Table 1 illustrates drilling activity by year completion and shows the location of all exploratory well and most boreholes. The cumulative seismic coverage is approximately 52,000km; 28,000 km offshore and 24,000 km on shore, including the interior rift basins.
Phase 1: 1952 – 1964
BP and Shell were awarded concessions along the coast including the islands. Extensive geological work was conducted including the drilling of more than 100 stratigraphic shallow boreholes, gravity, aeromagnetic, and reflection and refraction seismic surveys. A thick sedimentary section was identified and four wildcats were drilled, one each on Zanzibar, Pemba, and Mafia Island and another onshore in the Mandawa Salt Basin. Although the wells did not encounter significant hydrocarbon shows, they confirmed the presence of reservoir and source rocks in the stratigraphic column.
Phase 11: 1969 – 1979
The State Company, Tanzania Petroleum Development Corporation (TPDC) was established and the first Production Sharing Agreement (PSA) was signed with AGIP on former BP/Shell concessions. During this period large regional, on and offshore, seismic surveys were conducted. AGIP, joined by Amoco in 1973, drilled three onshore and two offshore wells, including the significant gas discovery at Songosongo in 1974.
Phase 111: 1980 – 1991:
Adoption of the Petroleum (Exploration and Production) Act of 1980 and high oil prices encouraged increased activity. Most of the drilling in Tanzania occurred in this period, including the delineation of the Songosongo Gas Field and the gas discovery at Mnazi Bay, (1982) by AGIP. TPDC participated in Songosongo development drilling, two wildcats at Kimbiji and several seismic programs. Increased interest in the interior rifts, partially as a result of Project PROBE, resulted in Amoco drilling two wells in the Rukwa Rift basin. Shell drilled Dira-l, in the Mafia Channel in 1991 and relinquished the license in the same year.
Phase IV 1992 – 1999:
At the start of this there were no active concessions and little activity except for various studies, and a dedicated effort by the authorities to achieve fiscal and technical agreements for the development of the Songo Songo gas field. TPDC, Tanesco and Canadian Companies Ocean and Trans – Canada pipelines, are actively working on the Songo songo gas field development, transmission and utilization. Beginning in 1995 a number of international companies acquired exploration licenses in the coastal basins. Tanganyika oil Company in 1996/97 drilled two wells in the Mandawa Basin. Exploration agreements have been signed with Antrim and Canopy both of Calgary, Alberta, Canada, Gulf western Mining of Cyprus, Ndovu Resources of Australia and others are under negotiation, Agreements develop the Mnazi Bay gas discovery and to build a power generation plant are being negotiated.
The petroleum exploration database in Tanzania consists of numerous geological and geochemical studies, geological and drilling records from more than 100 boreholes and 33 deep wells and many thousands of kilometres of gravity, airborne magnetometer, and seismic surveys. A summary of each well, a full list of electric logs, mud logs, geological and engineering reports, and composite logs are available for inspection at TPDC’s Exploration Office in Dar es Salaam. Several technical reports have been prepared from these data and provide an assessment of the hydrocarbon potential of Tanzania. Data packages for each of the exploration areas are also available for purchase.
Geology and surface Information
The country was initially mapped by the Tanganyika Geological survey now based in Dodoma, and maps are available at a scale of 1: 5000 Only twenty – five wildcat exploration wells and eight development wells have been drilled in Tanzania, over a sedimentary areas, more than 700 km long and 400 km wide, A number of these wells, both early and more recent, were located on the basis of poor quality or inadequate seismic control and in retrospect, were invalid structural tests. Other wells were drilled on the less prospective basin margins.
Magnetic and Gravity Surveys
There is excellent coverage of aeromagnetic data over Tanzania onshore and offshore the data include magnetic surveys of 1977 by aero survey for AGIP and 1976 surveys are in the form of maps and are part of the data packages. The coverage of gravity data is patchy consisting mainly of regional surveys; the best coverage is in the coastal areas over the Mandawa and Ruvuma basin, the larger offshore islands and in the Rukwa Rift Basin. In the Ruvu, selous and Rufiji areas the gravity coverage is limited mainly along the recently acquired seismic lines.
A total of over 24,000 km of onshore seismic data and 28,000 km of offshore seismic data have been recorded n Tanzania, Details of all seismic surveys with a listen of acquisition and processing parameters and a shot point map at a scale of 1:500,000 are provided in the technical reports. Most of these data can be obtained in the form of paper prints and films. A certain amount of digital data is also available. Hydrocarbon Occurrences. Source: Tanzania petroleum Development Corporation Date: 1 January 2000.
The known oil seeps of Tanzania are located at Tunduma on the west coast of Pemba Island, Wingayongo and at Msimbazi near Mnazi Bay and in the Interior Rift Basins. The Pemba Island seep indicates a marine source, which has been correlated with Campania – Maastrichtian shale’s. However, the typing of the seep does not correlate with oil shown from the nearby Pemba-5 well. It appears that two separate sources are involved. The wingayongo oil seep at the northern flank of the Rufiji Trough shows unusual biomarker characteristics, which have been interpreted to be derived from a source rock deposited in a restricted carbonate lacustrine environment. The Makarawe shale (Bajocian) is a possible source of this seep.
East Lika – 1 Oil stains and cut fluorescence in Middle and Lower Jurassic, Kimbiji East – 1 Good gas show in Eocene and paleocene Kimbiji Main – 1 Poor gas show, Kisangire – 1 Middele Jurassic bitumen stain kiwangwa Trace oil show, high mud, gas, Lukuliro 1 Gas shown in Lower Jurassic Mafia – 1 Oil and gas shown in Lower Tertiary, Makarawe – 1 Trace oil, high mud gas in Middle Jurassic, Mandawa – 7 free oil in Nondwa Shale and Mbuo claystone Mbuo – 1 Oil fluorescence, Mita Gamma – 1 Oil stain, streaming fluorescence, Mnazi Bay – 1 Gas Discovery in Miocene/Oligocene sands, oil shows in Upper cretaceous/Upper Tertiary, Pemba – 5 Minor oil and gas shows in Eocene/Oligocene, Ras Machuisi -1 Mud gas at base of Tertiary, Songo Songo-1 Gas Discovery well in Lower Cretaceous Songo Songo -2 to 9 Development wells in lower cretaceous, Tan Can-1 Minor gas in Paleocene, Zanzibar-1 Minor gas in Eocene limestone.
Lindi – 1 Minor oil show and gas kick, Mtwara – 1 Bitumen staining and gas in Miocene sandstone, Pindiro-1 Wet gas in Lower Jurassic, wingayongo-1 Bitumen staining.
Msimbazi seepage I bituminous and, wingayongo olive oil, Pemba Island Oil seep, Lake Tanganyika sub lacustrine flow of asphalt, Seeps at Msimbazi near the Mnazi Bay gas discovery indicate two families o oil; one is interpreted to be generated from a carbonate source rock deposited in a strongly reducing environment; the other contains significant terrestrial organic matter and biomarkers of Late cretaceous or younger age. A number of oil seeps and slicks have been reported from the interior Rift Basins. Oil seeps were reported from Lake Tanganyika as early, as 1896 and in more recent times, project PROBE found an oil film on the lake. Oil shown have been reported from the Pemba – 5 Mandawa Mafia – 1 Mita Gana -1 well. Cut fluorescence and staining from seven other wells and three boreholes have been observed. Songo Songo wells yielded small amounts of oil, which are low in sulphur with 33o – 47o API.
Commercial gas discoveries have been made at Songo Songo and Mnazi Bay, while gas shown have been encountered in several wells and boreholes, gas seeps have been reported from several locatives in coastal and inland basins.
Songo Songo Gas Field
The field is located on and offshore songo songo Island (figure 7) about 15 km from the mainland and 200 km south of Dar es Salaam. The discovery well, Songo Songo was drilled in 1974 by AGIP. Songo songo is a large N-S trending structure containing one to two TCF of gas reserves. The gas is contained in Lower cretaceous inner shelf sand reservoirs with porosities averaging greater than 20% and net porous intervals up to 155 m thick. The structure was uplifted during the Early cretaceous and the reservoir modified by the mid cretaceous regional unconformity. The trap consists of two faulted highs separated by a saddle. A series of N-S and NW-SE trending faults steps down to the east. This faulting regional eastward tilting and rapid tertiary sedimentation created more growth faults which mostly sole out in the sealing shale’s of the upper cretaceous Ruaruke formation. The lower cretaceous reservoirs are not affected by this later episode of faulting continued activity along these faults not affected by this later episode of faulting. Continued activity along these faults resulted in the development of broad, low relief anticlines. The gas appears to have been sourced from post mature organic material of Jurassic or Early Cretaceous age. The associated liquids are probably sourced from mature organic matters of early cretaceous and middle cretaceous age and seem to have migrated from a nearby basin.
Mnazi Bay Gas Discovery
AGIP drilled the discovery well, Mnazi Bay-1 in 1982. The well encountered commercial quantities of gas in two Oligocene sands within the Mnazi Bay Clay Formation. These sands have porosities of 15 to 25% and permeability’s up to 560 md. Drill stem tests produced flows of 3.5 × 105 m3/day (12.5 MMCF/d). Based on one well and seismic coverage, the reserves at Mnazi Bay are estimated to be in the 1 TCF range. The gas is considered thermogenic but no source identification has been made.
Source Rock Characteristics
Oil prone source rocks have been identified in the Lower to Middle Jurassic Pindiro or Nondwa carbonate/evaporates, as shown in the Mandawa-7 Mbuo-1 and Mita-Gamma-1 wells. They contain a rich mixture of Type 1 and III kerosene with TOCs greater than 9% (Figure 8) The permo – Triassic and possibly even some early Jurassic sediments are dominated by Type III kerosene, although rocks with TOC of 7% and a Hill of 386 mg HC/g TOC occur in the lukuledi-1 well in the Ruvuma Basin. The section above the Middle Jurassic is typically, dominated by Type III kerosene and is essentially gas prone. The upper Cretaceous in Kimbiji East – 1 contains TOCs up to 12% cretaceous and Tertiary source potential has also been speculated, Eocene lignite’s and organic rich shales are present in wells around the Songo Songo Gas Field. Occurrences of oil in a Songo Songo well and in the Pemba – 5 well have been described in the preceding section on Hydrocarbon Occurrences.
Basin studies chemical analysis and burial history and maturation modeling indicate that extensive hydrocarbon generating kitchens are likely to occur within the basins. Hydrocarbons generated in the Karoo basins may have accumulated in reservoirs of the same age, or migrated into Lower Cretaceous sands. The regional upper cretaceous shale’s of the Ruaruke hydrocarbons generated in the lower cretaceous shale’s in the distal (offshore) areas could be expected to migrate laterally and up dip into the younger cretaceous and Tertiary sequences. The interior Basins contain lacustrine Karoo sediments (4 to 5% TOG) with 30% Type 1 and II kerosene. The tertiary lake Bed Formation contains up to 4.9% TOG, consisting of Type I and II kerosene. All the required elements for successful petroleum systems have been observed in Tanzania. These are manifested in two commercial gas discoveries, at Songo Songo and mnazi Bay, numerous oil and gas shows, e.g. Pemba, Makarawe, Songo Songo, and oil seeps at Mnazi Bay, Wingayongo and Pemba Island. The basins of Tanzania have good potential for both oil and gas production. The interior Rift Basins also have elements necessary for an effective petroleum system.
The overall regional geological framework of Tanzania was discussed on page 14. The following section is an introduction to the descriptions of the individual basins of eastern Tanzania. Each basin description contains information about exploration, geology, and hydro-carbon occurrence.
Source: Tanzania Petroleum Development Corporation DATE: 1/1/2000.
Area: 50,000 km2
Database: one well; 4700 kmof seismic; aeromagnetic; land sat.
Tectonic framework: permo-triassic ne trending rift containing up to 10 km of sediments; failed in early Jurassic.
Structural style: large basement highs; growth structure anticlines; tilted fault blocks; horst blocks.
stratigraphy: permian-triassic (karoo) clastics, deposited in fluvial, lacustrine, deltaic to possibly marine environment.
Drilling results: liwale-1 (shell 1985), d&a at 1762 m; tested a highly faulted and cemented continental Clastic Triassic section on the eastern flank of the basin.
Potential: large untested structures, thick sedimentary section, good source rock potential.
The basin covers about 50,000 Km2, is sparsely populated, and includes the open savannah of the selous game reserve. The basin fill consists of over 10 km of karoo and post- karoo fluvial-continental, lacustrine and possibly, some marine sediments. It is virtually unexplored, with only one shallow well, liwale-1, drilled by shell in 1985 after acquiring about 4700 km of seismic in 1982 – 83. The well was abandoned in Late Triassic sediments at 1762 m. The selous Basin is a failed rift, which was active during Permian Triassic extensional rifting and filled with synrift sediments. Seismic data indicates several basements horst features with faulted rollover anticline structures and down faulted blocks against basement. Landsat and aeromagnetic data provide an excellent outline of the basin and agree with the seismically interpreted basement configuration.
Early Permian sediments have been postulated in the selous Basin from seismic and outcrop data and are believed to be several thousand materials thick in the half grabens developed during the first major rifting episode, Outcrops of Karoo sediments occur in the southern part of the basin and along the Rufiji River valley to the north. The sediments in the south consist of fluvial and swamp deposits containing coal seams of industrial value of in the north the deposits are lacustrine – deltaic with reported evidence of brief marine incursions. Analogy is made to good source rocks documented in similar rift environments of the same age in Africa. E.g. Middle sakamena Formation at the Permo – Triassic boundary in the Morondava Basin of Madagascar and maji ya chumvi formation or ‘fish bed’ at the same stratigraphic level in southeast Kenya. Lacustrine source rocks are also common. Source rocks in the selous Basin include Lower and Upper Permian shales with TIOG values of 2.2 to 9%
Analogy is made to good source rocks documented in similar rift environments of the same age in Africa e.g. Middle sakamena Formation at the Permo-Triassic boundary in the Morondava Basin of Madagascar, and Maji ya Chumvi Formation or Fish Beds at the same stratigraphic level in southeast Kenya. Lacustrine source rocks are also common. Source rocks in the zealous Basin include Lower and upper Permian shales with TOG values in the 1 to 6% range and Rho values of 0.6to 2/3 Triassic black clay stones in the liable well recorded by shell to have TIOG values of 2.2 to 9% Potential reservoirs in the basin include Karoo clastics with porosities ranging from 10 to 15% and permeability’s ranging from 0.4 to 1700 md (average 62 md) improved porosity and permeability development is expected in the middle of the basin where sediments will be better sorted and contain a higher amount of coarse grain classic material. The hydrocarbon plays in the Selous Basin are expected to be mostly intra-karoo, containing the essential elements of reservoir source and seal associations. Trapping would involve fault related, basement blocks, roll over’s along major faults and drapes over basement highs The structural style of the basin: This seismic profile on the eastern side of the basin illustrates an undrilled growth structure north and east of the liwala – well shoes total depth of 1762 m equates to about one second two way seismic time.
Source: Tanzania Petroleum Development Corporation Date 1 January 2000
Database: One exploratory well 2600 km of seismic gravity aeromagnetic.
Tectonic Framework; Late Jurassic east west subsidence imprinted on the northeast extension o the failed Permian – Triassic serous Basin the Rufiji Trough extends eastward to the Rufiji River Delta.
Upper cretaceous Black, deep water shale’s deltaic/turbidity sands.
Lower cretaceous Deltaic, fluvial sands.
Middle Jurassic Marine shale’s, thick carbonates, up to 800 m
Lower Jurassic Black carbonaceous muds
5. Permian Triassic Fluvial continental sands.
Drilling Results: Lukuliro – 1 (shell 1985) DM at 2367 m gas shows reported in the lower Jurassic.
Potential; Large truncated, Permian to Jurassic, fault blocks overlain by cretaceous sands; Mid Jurassic carbonate platform build up and reefs.
The Rufiji Trough is a major east west trending basin separating Masasi Basement Spur in the south from the Dar es Salaam platform to the north. The northern flank of the Trough merges with the Dar es Salaam platform approximately 40 km north of the Rufiji River Delta. It stretches from the basement in the west to the Rufiji River Delta. The one exploratory well, Lukuliro encountered 800 m of middle Jurassic platform carbonates gas shows were encountered into lower Jurassic.
Through is a composite basin, comprising part of the failed rift system in the west and Jurassic Rift Basin in the east (the Rufiji embayment) the major structural trends are inherited from these two elements. The major structural trends are inherited from these two elements. The NNE element associated with permo – Triassic continental rifting the E-W elements parallel to the regional lineaments which were initiated or reactivated into the early Jurassic. The resultant structures are inters basined thank horst and tilled fault blocks. It is also postulated that the Rufiji Trough is a restricted basin similar to the Mandawa salt Basin although little evidence of mobile salt can be shown due to paucity of dat. Salt springs and salt water wells at Kipatimu indicate presence of salt in the sub surface.
Despite the presence of the songo songo gas field just of share to the east at the area a significant oil seep at wingayongo on the northern flank of the Trough and hydrocarbon impregnation in the Middle Jurassic limestone at Kipatimu on the southern flank, the Rufiji Trough is the least explored of the Tanzanian coastal basins. No well has been drilled in the Rufiji Delta area. There is fairly good regional seismic coverage around the Lukuliro location but virtually none in the delta area. Gravity control is available along the coastal and Rufiji River Delta areas Potentially rich; Mostly Jurassic source rocks have remained not the oil window for a long time and still remain there. An oil seep at wingayongo indicated that this Trough has oil potential Play types include: Triassic fault blocks and rollover anticlines carbonate platform reef and limestone: Triassic fault blocks ad rollover anticlines carbonate platform reef and limestone listric fault rollover structures in the Rufiji River Delta areas.
The carbonate bank section encountered in the Lukuliro I well was also penetrated in the Kisangire I well to the north of the Trough. There is also undrilled seismic anomaly at the carbonate bank level. One of several features in the area Featured with seismic line showing tilted blocks beneath the Middle Jurassic unconformity, reminiscent of the present North as prospective lower Jurassic and Triassic sections.
Source: Tanzania petroleum Development Corporation Date January 2000
Five wells: 3700 km of seismic gravity aeromagnetic maps and tapes.
Tectonic Framework: An early Triassic to Early logistic rift basin containing lower Jurassic evaporates salt tectonics active during the passive margin phase (cretaceous to Tertiary)
Structural style: Tilted fault blocks in the pre – mid Jurassic salt cored anticlines trending NNW.
Stratigraphic: Oligocene/Miocene – Deltaic sands, Eocene carbonate platform Palaeogene classics and reefal limestone’s lower cretaceous.
Sands and silts, minor limestone’s, mid upper Jurassic classics carbonates during salt tectonics, Triassic/Jurassic marine fluvial sands shales and evaporates (oil prone).
Drilling Results: Mandawa – 7 (BP/Shell 1959)) D&A 4065 oil shows, kizimbani (AGIP 1979) D&A at 2697 m Mbuo – 1 1996) suspended TD at 3313 m oil shows, Mita Gama 1 (Dublin INT. 1996) suspended TD at 2390m oil shows East lika -1 (Dublin int. 1997) D & at 2002 m.
Potential: Tilted fault blocks pre middle Jurassic sub crop and stratigraphic plays cretaceous structural and stratigraphic plays associated with salt structures roll over’s on the down side of tertiary growth faults.
The Mandawa Basin lies along the south-east coast, south of the Rufiji Trough and north of the Rufiji Trough and north of the Ruvuma Saddle. It is unique in being the only drilled salt basin in East Africa. This basin contains a thick Jurassic section containing excellent oil prove square rocks. Three wells drilled salt related features. Two later wells drilled in 1996 and 1997 penetrated thick Jurassic sequences with fluorescence shows and a considerable thickness of reservoir quality sandstones and limestone’s. The late Triassic – Early Jurassic age of evaporates indicates that rifting into the eastern side of the Masasi spur was younger than the same phase in the serous Basin to the west. Before the Middle Jurassic marine incursion this area was already an evaporate basin. Subsequently, the salt formed ridges and became the core of several anticlines treading NNW in response to the Mid Jurassic Mid cretaceous N-S right lateral wrenching that affected the region during the rift of Madagascar along the Davie Fracture Zone.
Lower Jurassic sediments are the dominant salt basin fill, which was then overstepped by the post rift Middle and upper Jurassic passive margin development and the accumulation of a predominantly classic delta wedge continued thought the cretaceous and Tertiary thickening from west to east. There was little deposition in the salt basin after the early cretaceous. The lower Jurassic Nondwa evaporates and Mbuo shale’s are the most promising proven source rocks in Tanzania maturity modeling indicates a large early Jurassic kitchen area with oil generation from the Early Jurassic to the Middle cretaceous. In Mandawa – 7 a section of over 1000 m of Mbuo Formation includes abundant black shale’s with average TOC values of 4.7% Kerogen type is appropriate for oil and gas, consisting of a 22m section of Mihambia Formation with a TOC of almost 4%. These measurements increase the prospectively of the post salt plays which still remain untested. Petroleum generation could also have occurred outside the Mandawa Basin to the east in what is now the coastal offshore basin where potentially rich rift sediments could have generated hydrocarbons porous intervals encountered in the wells include the salt sandstone or Early Jurassic age and as interbreeds within organically rich shale’s (Mbuo – 1) in addition the salt capping limestone of Mid Jurassic age with other shale encased porous sand bed of Jurassic age (Kizimbani (1) provide significant encouragement of the hydrocarbon potential of this basin.
INTERIOR RIFT BASINS
Source: Tanzania Petroleum Development Corporation Date January 2000
Date Base: Two wells 6000 km of seismic gravity, aeromagnetic maps and tapes.
Tectonic Framework: Early limited rifting in permo-carboniferous and lower cretaceous, with significant extension tectonics since early Miocene.
Structural style: Eastward thickening half grabbers with major boundary faults.
Stratigraphy: Miocene quaternary continental locustae silly sandstone moods cretaceous continental redbuds carboniferous karoo titbits and coals,
1. Galole – (Amoco 1987) D&A at 1524 m
2. Ivuna -1 (Amoco 1987 D & A at 2316m
Potential: Tilted fault blocks horst graven structures drape features stratigraphic traps
The East Africa Rift System is represented in Tanzania by lake Tanganyika, Lake Rukwa, Lake nyasa and the Ruhuhu Basins. The prospective sectioning the lake area lies mostly beneath the water in depths o up to 15000 m . Only two wells have tested the interior basins Amoco and partners drilled the wells into the Rukwa Basin and the penetrated thick section of Tertiary to Triassic sediments, oil and gas seeps have been reported in and around the lakes, Rift valley exploration has yield significant discoveries in many parts of the world and by analogy the east African interior Rift basins also merit further investigation.
Basin evolution many have started in the permo – carboniferous with karoo deposition accentuated by rifting into the lower cretaceous and followed by intense extension tectonic activity since the early Miocene. The basin fill is a thick continental lacustrine sequence of Neocene to quaternary age, overlying an equally thick sequence of Permian and Mesozoic continental deposits. In profile these rift basins are half with the sedimentary section thickening towards the major bounding fault. Early geological studies into the late 1940 an 1950 focused on the coal potential in the Rukwa area. Woods Hole Oceanographic institute carried out the first geographic survey team on Central lake Rukwa (1973) and by a Chinese team, as part of their study of the petroleum geology of Tanzania (1977).
Between 1981 and 1986 about 2000 km of seismic data was acquired by Duke university project PROBE program for a consortium of oil companies, Petro – Canada conducted a gravity survey for TPDC in the Rukwa Basin (1983) followed by another gravity survey by nor consult (1985) in the Lake Nyasa Ruhuhu Basins. Amoco with partners Pectin and Fina were granted the first exploration license into the basin in 1985 and carried out geological field work, gravity survey and acquired about 4000 km of seismic dat. This group drilled in 1987 two exploration wells in the region both galula and vicuna I were dry holes.
Reservoir potential in these basins is known only from outcrops and the two Amoco wells. However, evidence from analogous rift valley sedimentation illustrates potential for classic reservoirs in the karoo (over 12% porosity and up to 1320 md permeability’s average 143 Red sandstones (13 – 25%) porosity range) and the lake bed formation (17% porosity and 25% porosity range) and the lake Bed Formation (17% porosity and 25 md permeability). The best quality oil source rock is in the lacustrine karoo sediments (4 to 5% TOC) overlying the coal beds, with 30% type I and II kerogen. The next best oil prone source rocks is in the Tertiary lake Bed formation in the Rukwa Basin, This formation contains up to 4.9% TOC consisting of Type I and II kerogen. Rukwa rift Basin maturation models indicate the top o the oil ozone between 2000 and 2500 m Similar results have been reported from Lake Tanganyika where a potential kitchen area forms a strip about 25 km wide and 130 km long in the central Bain of the lake.
Source: Tanzania Petroleum Development Corporation Date 1 January
Data base: three wells 28000 km of seismic gravity aeromagnetic
Teklanika framework: Narrow Permo Triassic remnant o selous failed n\rift extension with superimposed tertiary sag basin
Structural style: early title fault blocks wit early cretaceous truncation down to the basin tertian faulting
Stratigraphy: Eocene shale’s sands and limestone’s upper cret/pal turgidities lower/mid crept near shore shelf sands permo -Triassic continental fluvial clastics
1. Ras Machuisi – 1 (AGIP 1974) D&A at 3370 m Eocene gas show shallow offshore well.
2. Makarawe -1 (IEDC 1984) D&A at 3821m Jurassic gas show.
3. Kiwanawa -1 (kifpec 1986) D&A at 3514m gas show.
Potential: Large tilted permo – Triassic fault block; other faulted anticlines in Lake Mesozoic rocks; rollovers into Tertiary growth faults.
The basin covers the onshore region from the western Dar es Salaam platform to the Kenya border. The serous/Ruvu permo-Triassic failed rift narrows down to 20-30 km and occupies almost entirely the onshore portion of this area. There is no cretaceous platform equivalent to that of the Dar es Salaam platform. The Ruvu Basin evolved into thermo Triassic/early Jurassic and is the north-easterly extension of the serous Basin failed rift. The Tanga Fault marks the western limit of the basin. To southeast, the basins bound by the Kisangire and Pugu highs of the Dare s salaam platform. The eastern limit of the Ruvu Basin coincides with the present day coastline .with the present day coastline. The cross section illustrates the positions of the Ruvu Basin in the west and the down to the basin tertiary faulting into the Zanzibar channel.
The sedimentary fill consists of Permo – Triassic to Neogene sediments. There wells have been drilled in this basin Makarawe in the north Kiwangwa in the south and Ras machuisi just offshore in the central area. All three wells encountered gas shows at various starts graphic levels. Geochemical data indicate that the area has potential for soil generation. An oil prone source rocks (TOG up to 4%) was encountered in the Bajocian shales in Makarawe. The potential reservoir targets are permo- Triassic to lower Jurassic fluvio – continental classics , middle Jurassic carbonates apptian/albian sandstones (equivalent to the songo songo reservoir section ) and limestone’s, and upper cretaceous sandstones. Structural style of the Ruvu Basin, indicating down to the basin faulting the folding in cretaceous and older sediments. The kiwangwa 1 well, on the western side of the profile was drilled to a total depth of 3514 m encountering mostly shales with zones of interbeded sandstones towards the bottom of the well. A minor gas show (CI-C4) was encountered near the top of the lower Jurassic (blue seismic marker).
Source: Tanzania Petroleum Development corporation Date 1 January 2000.
Area: 16,000 km
Database: Two wells 1800 km of seismic gravity and aeromagnetic maps and tapes.
Tectonic framework: A late Triassic to early Jurassic rift basin which was succeeded by passive margin sedimentation from the middle Jurassic to tertiary
Structural style: Rift phase normal faults passive phase district down to basin tertiary faults along the coast
Stratigraphy: Oligocene lowstand mostly deltaic classic (Ruvuma delta) Eocene regressive sands, local limestone Palaeogene clays minor sits and sods, upper crept passive margin arils and shale’s lower crept regressive sands with minor conglomerates and salts,
Upper Jurassic – Shallow marine shelf sands, lower Jurassic continental to restricted marine sediments permo Triassic sandstones
Drilling results Mnazi Bay -1 (AGIP, 1982) gas discovery in Oligocene deltaic sands
Lukuledi-1 (Texaco 1990) D & A at 1941m.
Potential: Cretaceous and Tertiary low stand plays on and offshore, stratigraphic traps below cretaceous canyon cuts large roll over structures on the down side of Tertiary growth faults Jurassic reservoirs in rift grabbers and carbonate bank edges
The Ruvuma Basin is situated in the south-eastern coastal zone of Tanzania adjacent to the Mozambique border, The Tanzania parties between the Ruvuma River and Ruvuma saddle, and is bounded on the west by the Maasai Basement spur and on the east by the shelf break, It is about 16,000 km2 in area, including the narrow 10 – 15km wide shelf offshore. BP commenced early exploration followed by AGIP drilling the Mnazi Bay discovery in 1982. Texaco drilled the second well lukuledi – 1 in 1990
There are two district structural styles displayed in the Ruvuma Basin. During the rift phase, a NNE SSW trending horst and graven structural style developed in the pre – upper Jurassic section. This section dips regionally eastward due to subsequent passive margin loading. The passive margin section is unstructured except for the Tertiary epicentre at Mnazi Bay where district faulting has developed a large gas bearing structure. The section thickens eastward and southward to the Ruvuma River (the postulated site of a transform fault zone.) Another transform fault zone to the north could have resulted in the up thrown Ruvuma saddle, which separates this basin front eh Mandawa salt Basin to the north.
The basin fill includes pre – Jurassic sediments with minor marls and early Jurassic restricted marine deposits flanked by continental sediments of the basin margins. The middle Jurassic to Neocene section is a thick transgressive and regressive sequence. Depth to basement is estimated to be 7 km at the coast deepening seaward. In the onshore, basement, block faulted province, mainly continental to marginal marine send, dominated sections have gas source potential an some possibility for oil generation (locustae, type kerogen) porosity 22% and permeability’s of several decries) This well also confirmed the presence of middle upper Jurassic reservoir quality marine shoreline sandstones of the mtumbei Formation with porosities exceeding 20% and good permeability’s.
In the coastal to offshore province, gas prone source rocks are present, as shown by the Mnazi Bay discovery, where gas has migrated from deeper levels along listric faults. This well encountered oligo-Miocene sands stone with porosities of 16 to 24% and excellent permeability. The bitumen seeps occur nearby point to oil prone source rocks in the area. One of these sources is interpreted to be in a carbonate section deposited in a strongly reducing environment (lower to Mid Jurassic carbonate and shale sequence) and the other sources interpreted to contain a significant terrestrial component of late cretaceous or younger age.
The msimbati oil seep, south of Mnazi By and minor shows in wells and boreholes indicate potential for oil source rocks at depth. The lukuledi well penetrated a permo Triassic section which had TIOC values of up to 7.5% and an above average hydrogen index of 38 mg HC/g TIOC it is possible that the companion age black shale’s identified in the kimbiji area to the north were also deposited in the coastal and shelf area of the Ruvuma Basin. This shale’s contain TIOC values of up to 12% are oil prone and will be mature where buried under the tertiary Ruvuma delta.
The nuclear energy sources no renewable. Nuclear energy is produced as result of the reaction of the nuclei of radioactive metals like uranium. This leads to the alteration of the atomic structure and during this action much energy is generated in the form of heat, which can be used for generating electric power.Alteration of the atomic structure involves either of these processes.
1. Nuclear fission in which the nucleus of a heavy element like uranium splits into smaller particles releasing energy.
2. Nuclear fusion in which the separate light atoms like those of hydrogen are fused to form a new composite nucleus at meanwhile releasing emery. Fusionism commonly used in p repairing the hydrogen.
3. There are about 20 countries that have nuclear power plants, the example of the countries that have developed nuclear power station are Britain (with about 35 power stations) USA with about 80 plants frame with about 36 plants the former USSR with about 43 plants, Japan with about 28 plant others are Germany, Canada, Sweden, Belgium, Spain, Switzerland, India, Pakistan, Namibia Niger south Africa.
1. 4. It is used in producing heat and generating electricity.
2. 5. It is also used in making nuclear weapons like bombs.
3. 6.The current trend is that nuclear energy is expected to play a major role in the future. This is because of the following reasons.
4. 7. Increasing coasts of fossil fuels. The prices of that fuci are soaring high to a great extent.
5. 8.The fossil fuel resources are diminishing because of excessive exploitation.
Advantages of Nuclear Energy
1. -It is clean and produces fewer green house gases. Hence, it is less pollutant if well handled.
3. -It is more economical since it used very small amount of raw materials. Therefore, it is less bulky compared to coal and hence transportation is not a big problem.
4. -It is produces little amount of waste.
5. -The possession of nuclear energy enhanced the generation of electricity. Moses of the developing countries now are opting for nuclear power as an electricity such countries are like Egypt and India.
6. -Minerals used as raw materials are mined in areas where people end to benefit in terms of employment, infrastructure, income generation etc.
7. -The power produced can be exported and hence bring the foreign currency to be country.
1. -It contributes to environmental problems like water pollution, air pollution leading to different effects not the organisms radiation produced is dangerous like the Chernobyl l leakage in Russia which led to different problems like cancer leukemia deaths of people animals and plants. The explosion took place in 1986. The solution was that we, Canada and the European community began negotiation with Ukraine and Russia to close down all remaining Chernobyl type rectors. The case of Hiroshima and Nagasaki led to the death of about 80,000 people and mammy other got disabilities hitherto.
2. -Building the nuclear plant is very costly therefore it demands high capital.
3. -There are proems of disposal for wastes since the waster are radioactive.
4. -It disturbs the security o the countries in the world. For example it has accelerated the rate of terrorism in the world, which involve bombing of important places like the American embassies in Kenya and Tanzania. Also it has led to the escalation of conflicts between India and Pakistan where tug of war involves the use of nuclear bombs.
5. -Disposal of radioactive wastes is very difficult and costly.
6. -There is also a problem of choosing the sites for locating the nuclear reactors since it need a place which is very far from the settlement areas so as to avoid the accidents like what happened in Ukraine in 1986.
Hence when the nuclear energy us handled properly or used appropriately it can bring great benefits in terms of development but it mishandled or misuses in can head to horrendously hazardous effects to the whole global community at large.
The future of the Nuclear energy:
-It is tempting to argue that as nuclear power stations become more economical and supplies of conventional fuel energy sources became more difficult to obtain, nuclear power will overtake other forms of sources of electricity.
-It is fair to say that nuclear power will play a much more prominent role in the future power supplies but it will never entirely replace conventional fuels due to the following limiting factors.
1. -People oppose the use of this energy as it generates some wastes which are difficult to manage, and which have some negative impacts on the environment. Wasters also can lead to problems of health like causing leukemia and cancer amount the people.
2. -Nuclear power cannot generate at or near full capacity hence it is necessary to have other sources to support it. It is estimated that nuclear power can never supply more than about 60% of the total electricity requirement because it needs close attention. Too great amount can become difficult to manage.
-Locating nuclear power stations is a problem. While thermal power can be located anywhere, nuclear energy needs the area or site which is very far front he population centers. It is therefore a big problem in the crowded areas like European countries and Japan where the land is small.
4. -The existing plants or power stations are obsolete and will continue being used for a long time hence power will increase very slowly. This is due to the fact that buying new machines and establishing new plants is very expensive.
5. -Competition from other sustainable or environmentally friendly sources of energy like solar energy source, biogas, wind energy tidal energy etc. Nowadays there are countries which using solar energy to generate photo voltaic electricity, in which silica cells are used to catch sunlight and store energy in batteries. Therefore, there will be limitations in the extent of the nuclear energy use in the world.
NUCLEAR ENERGY IN JAPAN
Japan is referred to as the nuclear nation because of having many nuclear power stations. It produces almost 10% of world total while Russia produces almost 11%. Today over 9% of Japan energy needs are met by the nuclear industry. More centers are being developed and the percentage has been set to rise to 17% (40% of Japan electricity) by the year 2010. There is the aim for decreasing oil percentage from 58% to 46%
Nuclear Reactors in Japan
Japan first two nuclear reactors were built at the end of the 1960. By 1980 there were 13 reactors. This had to rise to 41 by the end of 1991 the target was to have 55 reactors by the end of 20th C. It has different types of reactors but is also experimenting with newer fast breeder reactors (FBRs) which use reprocessed nuclear fuel Japan is already having a new uranium enrichment plant and is building a new fuel reprocessing plant. Limitation Japan is facing in relation to nuclear energy development.
1. -Good sites for locating nuclear power stations are limited because Japan is mountainous while the nuclear plants need flat land and large water supply.
2. -Unstable land, which experiences over 7000 earthquakes every year is a problem. Nuclear energy needs stable land for safety but Japan is in the zone of convergence (weak zone).
3. -Pressure on the land is another problem. The land is small and several reactors are located on the same site. For example Wakasa bay has 15 separate reactors around it that cause the problem of pressure on land.
4. -There is an increasing opposition to the growth of nuclear power in Japan. A number of pressure group actively opposes the nuclear programme. Some like the CNIC citizens nuclear information Centre) regularly publish antinuclear information. Protests are becoming more common. The concern centers on possible radiation leaks and the difficult in the disposal of nuclear waster
It is non – renewable fossil fuel. It provided by trees. The main producers are the low economically developed countries (LDC) in Africa and Asia fuel wood can be converted to charcoal by heating the firewood under limited supply of oxygen. It is used for cooking, heating.
1 -It is easily available.
2 -The collection of fuel wood leads to deforestation, which in turn causes other problems like soil erosion desertification.
3 -It is non-renewable since replanting cannot keep pace with its consumption.
4 -It contributes to environmental pollution especially air pollution.
Renewable (sustainable – Alternative) Energy sources
1. Hydroelectric power (HEP) is power generated under the influence of the moving water.
Establishing the Generation Centre
1.The reservoir or dam or barrage is contracted normally across the river or along the coastal strip where tidal waves are common.
2. The powerhouse is contracted with turbines installed.
3. Then water is directed to the turbine chamber. Its pressure causes the rotation of the turbines.
4. As the turbines rotate the generators also rotate to produce electric power.
5. The power generated is then transported to the transformer from where it is transmitted to the consumer.
6. There should be reliable market where electric power can be supplier like the mining areas.
Necessary conditions for Harnessing HEP
The following are the conditions or factors necessary for harnessing or generating hydroelectric power;
1. -Reliable rainfall over high mountains so as to ensure the supply of water that can drive the turbines.
2. -Presence of big sources of water like rivers, lakes, oceans and springs so as to have a constant water supply. The volume of the river should not fluctuate
3. -Presence of a good site like waterfalls, impermeable rock base and narrow deep river stream where the dm and the power plant can be contracted.
4. -There should be enough skilled labour for contracting the dam and running the project.
5. -There should be reliable capital availability in order to construct the dam.
6. -There should be reliable market where electric power can supplied like the mining areas, homesteads, advanced mechanized agriculture and industries.
HEP Generating centres in the world
1. Kariba dam on the Zambezi River between Zimbabwe and Zambia.
2. Aswan high dam in Egypt on the River Nile.
3. The Akosombo dam in Ghana on the Volta river.
4. Inga dam in the democratic republic of congo on the Zaire river.
5. Owen falls in Uganda on the Nile River.
6. Kainji dam on the River Niger in Nigeria.
7. Seven forks in Kenya on the Tana River.
8. Mtera dam, kidatu dam, kihansi, Nyumba ya mungu dam, hale dam, kihansi, Rusumo falls etc in Tanzania.
9. Kabora Basa in Mozambique on the river Limpopo.
10. Kafue dam in Zambia.
11. Sennar dam in Sudan on the Blue Nile tributary.
12. Hedrick Verwoerd, Vaal, Torquay, P.K leroux dams on the orange river clan William dam on the olifants all in south Africa.
Advantages of H.E.P
1. It is very clean environmentally – friendly.
2. The reservoirs/dams can help in the control o floods and provision of water in the time of shortage.
3. It is often located in remote, mountainous areas where the population is low.
4. It stimulated the industrial development in the country. Eg iron steel industry in Sweden and electronic industries in south Korea have benefited a lot from the electric power.
5. It has led to the improvement in the communicating system like telecommunication, internet services, radio, TV and satellites that depend on electricity.
Disadvantages of H.E.P
1. The construction of dam leads to the flooding of large areas and people displacement like the Akosombo dam in Ghana.
2. It is easily affected by lack of rainfall and silting of the dams.
3. The pylons which are constructed can lead to visual pollution.
4. The dams also led to the outbreak of diseases.
North America HEP centers include Niagara Falls on the St. Lawrence River Hoover dam on the Colorado River and the Guntersville on the Tennessee River.
H.E.P IN AFRICA
Factor which favour HEP production of in Africa;
1. The presence of water bodies likes large rivers, lakes and the ocean that assure the supply of water.
2. The presence waterfalls that provide good centers for installing the turbines.
3. There is enough space for dam construction in Africa so that water and be kept for use all the year through.
4. Nature of the rock that s impermeable pre – Cambrian rock provides a good base for the construction of dams..
5. Political stability in same countries like Tanzania encourages the development of HEP centers.
6. Industrial development that has been taking place provides market for HEP.
Importance of HEP in Africa;
1. It stimulates the development of Industries.
2. Encourages the environmental conservation since it reduces the dependence of the forest for power.
3. It encourages the development of agricultural sector tourism and the mining section.
4. It promotes living standard of the people.
5. HEP can be exported to other counties and bring some foreign currency.
6. It encourages the development of science and technology especially in the communication system like internet service, radar , radio and Television.
Problems (bottlenecks) encountered when harnessing HEP in Africa;
Africa has a highest potential for HEP power in the world and it is thought to that tropical Africa possesses 23% of the world total potential of HEP. The potentials due to the presence of many rivers some of which have very large catchment areas and other water bodies great amount of rainfall especially in the equatorial zone and highlands and the presence of waterfalls. But it has least output of electricity (only 1%) due to the following limiting factors.
1. Seasonal fluctuation in the volume of the river, which make it difficult to turn the turbines. Sometimes the rivers are flooded because of high rainfall and sometimes they have very low volume of dry because of poor rainfall.
2. Excessive evaporation of water, which leads to the reduction of water in the rivers and other water bodies.
3. Water in the water bodies like the dam stands to disappear underground through percolation. This also causes the decrease in the volume of water.
4. Poor capital availability for constructing the dams. This is due to the fact that most African countries like Tanzania have poor economic base.
5. Inadequate availability of skilled labour like engineers and technician.
6. Poor market especially where the industrial base in poor. E.g Tanzania.
7. Lack of communication network of link the areas to production and the areas of consumption.
8. Destruction of the power lines or transmission cable as a result of civil wars some of the wires or cables are stolen by people
9. Silting of dams, which leads which leads to the reduction in the volume of the water.
10. Lack of appropriate technology among the people in the countries not all areas suitable for harnessing hydroelectric power are used because of the above factors.
HEP in Tanzania
HEP in Tanzania will continues being exploited because of the following factors;
1. It is relatively cheaply available compared to other sources due to its several HEP sources of high potential. For example there are many great rivers and lakes with high HEP potential.
2. Fossil fuel prices (eg oil) are increasing at a high rate.
3. There is a strong need to stimulate the fishing industry, mining agriculture and manufacturing at a high rate
4. Tanzania has embarked on the comprehensive programme of rural electrification and this can easily be done through HEP production.
5. HEP centers in Tanzania are so large hence not so dangerous to the environment. Hence the use of HEP will be one way of reducing the problems of deforestation hitting the country at large.
TIDAL POWER SOURCE
It is renewable; the power is produced when the tidal water along the coast drive the turbines. The main producers are France, the former USSR china and Canada. The tidal energy is used in producing electricity.
1. It is clean the hence does not pollute the environment.
2. The barrages built for tidal energy production help in protection the coast from erosion.
3. If the scheme is large a lot of electricity is produced.
4. The supply of tidal power can encourage the development of fishing industries.
1. Tidal power centres are very expensive to builds
2. There are few suitable sites into world. And the location should be along the coast; hence the areas far away from the coast cannot get disadvantages.
3. If can lead to the destruction of the coastal areas and disruption of shipping system.
It is renewable energy coming from the sun, it is used for direct heating drying clothiers and crops as well as production of electricity potential areas are the tropical areas where there is abundant supply and ikutha health centres in Machakos and Kitui districts ad some parts of Tanzania
Advantages of Solar energy
1. It could be used in many parts of the world.
2. The supply is unlimited (renewable energy).
3. It is non pollutant (it is clean).
4. It is efficient.
5. It is easy to install in new buildings.
6. Solar energy can lead to the development of tourism in the country where there is plenty of sunshine, For example in East Africa many supply of sunshine when it is winter back in their countries.
7. Solar energy provides vitamin D in the bodies, which is good development of strong bones. Deficiencies of vitamin D in the body can cause rickets in human beings.
8. Solar energy facilitates the rainfall formation through evaporation of water from the surface of the earth.
Disadvantages of solar energy
1. It is expensive to install and hence needs high capital for buying some equipment.
2. When it is cloudy or at night the supply of sunshine stops and hence leads to problems of energy supply.
3. It is unlikely to produce large amounts of energy compared to HEP.
It is the energy produced by the moving air mass. Wind is a renewable source of energy since it does not get exhausted. Wind energy can be used in generating electricity and pumping water from the deeper levels in the ground. It is also important in pollination of flowers, distributing rainfall by blowing the clouds regulating eh temperatures and accelerating evaporation. Areas where wind energy is used are Denmark California in USA UK where wind energy is used are Denmark California in USA, UK where there are many wind farms in Tanzania there several turbines, which have been installed in Singida and Dodoma for pumping water from the ground. The use if wind energy had been facilitation by the fact that Tanzania is blessed to have a consistent wind movement wind energy help in irrigation areas in the semi arid plateaus and generating electricity though at a small scale. The group of turbines installed at a certain place is referred to as wind farm.
Advantage of wind energy
1. It is very clean type of energy since there are no wasters produces like in coal or petroleum.
2. It is naturally non – pollutant to air and no problem of global warming.
3. It is cheap to harness or run.
4. Small scale and large scale schemes are possible.
5. It is used in producing electricity. This is done through driving turbines.
6. The land between the turbines can still be farmed.
Disadvantages of wind energy
1. Wind is unpredictable and not constant. When the wind stops the energy production stops too.
2. It leads to visual pollution and noise pollution in areas which are quiet
3. Many turbines are needed to produce a lot of energy and hence.
It is also a renewable energy source. It is the heat energy generated from the inertial of the earth. This is generated through volcanic eruptions like geysers and hot springs. Hot water from the ground can be tape through into the hot rocks that contain water. As water in thrown out with a great force it can drive the turbine which in turn can lead to the generation of electricity. Examples of the areas are Iceland, Kenya Japan, New Zealand the former USSR Mexico, El Salvador and Hungry in Tanzania potential areas for geothermal power Mbeya in Usangu valley, Arusha. The Rift valley province in Kenya is the potential area for producing geothermal energy. There is a geothermal station known as Olkaria near Naivasha with 16 well
Advantages of Geothermal Energy;
1. It is used for generating electricity and direct heating.
2. There are many potential areas especially where volcanic eruptions take place or have been taking place.
3. It can attract tourist and lead to the eating and warming the residential areas in winter.
4. It encourages the development of communication network like internet services which need electric power to operate
5. In cold area geothermal power is used for heating an dwarfing he residential areas in winter.
Disadvantages of Geothermal Power;
1. Hot water from the ground can introduce sulphur gases in the atmosphere when being tapped. This can later on cause acid rainfall.
2. Geothermal plants are expensive to develop.
3. Very high temperatures can create maintenance problem since some metallic parts can melt.
4. Geothermal power stations are developed in areas which are weak like the rift valley areas with volcanic eruptions. These eruption scan interfere with the supply of energy if the contraction has been poor.
Factors Limiting the Development of Geothermal power in Tanzania;
1. Poor or low capital available for being invested in the installation of the geothermal plants.
2. The presence of other sources of energy which are currently supplying power like HEP, fuel wood, wind oil etc.
3. Low rate of exploration of potential areas going on currently is another limiting factor. The researchers are costly.
4. Low market in the country since the country is still poor and it cannot afford the coast associated with the supply of geothermal power once it is established.
5. Low ability affording the charges for the supply.
6. There is low level of technology among many people of the country.
It is a renewable source of energy. It is derived front eh decay of plant and animal (including human) water matter. The gases produces as a result of fermentation or decay of these wastes include ethanol and methane gases. Biogas is used for heating, lighting and generating electricity. The main producers are Brazil, China, Japan, Germany, Denmark, India, Tanzania and Kenya.
Advantages of Biogas;
1. It is cheaply produces and widely used. It is affordable in the developing countries.
2. It needs intermediate technology (not advanced technology).
3. It can be used at a local level.
4. It helps in waste management since the wastes are recycled. Hence pollution in controlled.
5. The remnants from the digesters can be used as fertilizer in the farms to encourage crops production.
6. It improves the living standard of the people since they get energy which is cheap.
7. The gas can be exported to other countries and bring foreign currency.
Disadvantages of Biogas
1. It needs high care in handling otherwise it can cause destruction after burning because of careless handling.
2. People needs high care in handling otherwise it can cause destruction after brining because of careless handling.
3. It can be expensive to set up buying the digesters requires a lot of capital.
4. Emission of methane gas leads to air pollution.
5. Other wasters used as fertilizers can cause water pollution and spread of diseases.
BIOGAS IN TANZANIA
The systematic biogas popularisation programme in Tanzania was begun in 1975 by the small Development Organisation (SIDO) under technical cooperation agreements with khadi and village industries commission of India. Six demonstration plants of India design and with capacity ranging from 2 to 8 cubic metres were installed in various areas of Tanzania. The cost of these initial in plants ranges from 6000 to 8000 shillings.
By the end of 1979, 86 biogas plants had been installed in various regions of Tanzania. Out of those, 59 were working satisfactorily, the gas production rate of these plants ranged from 2 to 20 cubic metres of gas per plant per day. The 86 biogas plants were mostly at primary schools, rural health centres and rural training centres. It was anticipated that looting the biogas plants in rural areas would aid very much the transfer of this technology to rural areas and hence raise the standard of living as well as facilitate combating the problem of deforestation.
More plants have been established in many areas or regions of Tanzania these include Arusha, Mwanza, Tabora, shinyanga, Mara, Dar es salaam, Rukwa, Mbeya, Iringa, Tanga, Kagera, Morogoro (e.g. at Lutheran Junior seminary) Dodoma and Singida. Most of these biogas plants were constructed by SIDO. But recently local people are also involved in the construction. SIDO but recently local people are also involved in the construction. SIDO now considers that the demonstration phase of its biogas plants for community cooking, heating and lighting needs of be used for water pumping and electricity generation.
The ministry of energy and minerals has been engaged in feasibility study on the use of biogas to run small diseases engines of up to about 9kw (12hp) The objective is to reduce diesel fuel consumption in engines associated with rural supply.
What factors have influenced the development of biogas Tanzania?
1. The need to cut down costs on the other sources of energy.
2. To do away with over dependence on fuel wood as the source of energy in rural areas.
3. Abundant supply of plants and animals waster. For example the population of cattle in Tanzania than 11 million. This generates more than 40 tons of cow dung annually. This is large generates more than 40 tons of cow dung annually. This is large untapped biogas energy potential.
4. The need to raise the standard o life in the rural areas.
5. The government assistance through the missionaries e.g. in Mwanza at Kwimba, Tabora and Morogoro at Lutheran Junior Seminary.
Major constraints in the wide spread use of biogas energy in Tanzania;
1. Shortage of building materials for digesters.
2. Problems of transporting building materials and raw materials for the digesters.
3. Cost of digesters tends to the high thus most of local people cannot afford getting them.
4. People rigidity in accepting new technology because of being used to fuel wood. Traditionally most people have low level of technology.
Solar energy, wind energy, geothermal power, tidal power, ocean waves and biogas are currently advocated alternative energy sources because of the advantage that apart from being renewable, they are also environmentally friendly since they are largely less or non pollutant sources of energy.
Strategies for Tanzania to Harness Power and Energy Resources
1. The government should support the establishment of geothermal power generating stations like what is being done in Kenya geothermal power in more reliable than HEP.
2. There should be more emphasis on the use of wind, waves and biogas as well as solar energy in the villages. This is very important because electricity tariffs are very high and many people in rural areas cannot afford.
3. Constructing more water reservoirs like dams in order to ensure water availability all the year round.
4. Establishing some industries in order to expand market and attain an economic productive use of energy produced by centers like HEP stations etc.
5. Planting more vegetation in order than can provide biomass for energy generation.
6. Peace in the country should be maintained in order that the present energy sources can be expanded smoothly. Also when where peace there is can’t be destruction of the established energy production centers.
7. There should be population control so that the energy sources cannot be over exploited and lead to power supply problems and environmental degradation iron sheets for roofing the building etc
8. It also supplies energy since some minerals are energy resource like coal, petroleum, uranium and natural.
Factors that influence the development of mining industry include the following;
1. Availability of capital to be invested in the mining industry like buying the machines.
2. Nature of transport system. If the transport system is efficient mining develop fast but if the transport is poor then mining does not develop fast.
3. Labour availability is another factor that influences the development of mining sector. For mining to develop fast there should be ready available labour but if labour is not available then mining become poor.
1. Identify the conditions necessary for Harnessing HEP.
2. Show the advantage of HEP in Tanzania.
3. What are the obstacles limiting the development of HEP in Tanzania?
4. Explain how water can bemused in generating HEP.
5. Explain how water can be used in generating HEP.
6. Mention six hydroelectric power centers in Africa and their countries.
7. What should Tanzania do to improve its HEP potential?
8. Mention example of energy resources according to
(a) Non – renewable resources
(b) Renewable resources
(c) Thermal energy
(d) Fossil fuel energy sources
9. Define the following
(a) Non – renewable (Exhaustible resources)
(b) Renewable (or inexhaustible or alternative) resources
(c) Geothermal power
(d) Hydroelectric power
(f) Solar power or energy
10.Explain the origin of
(a) Oil (petroleum)
(d) Natural gas
(e) Nuclear power
11.Outline the uses of each of the following
(a) Solar energy
(b) Hydroelectric power
(c) Wind power
(d) Geothermal power
(f) Nuclear power
12.Mention the African countries where nuclear power is produced
13.Explain how biogas energy is produced
14.Account for the decline of coal as coal as the dominant power source in the world
15.Identify and explain the advantage and disadvantage of nuclear power providing concrete examples from any countries of your choice
16.Discuss the developed and potential energy sources in Africa
17.Outline the advantages and disadvantage of
(a) Hydroelectric power
(c) Geothermal power
(d) Solar energy
(e) Wind power
(f) Fuel wood and charcoal
18.Outline the economic importance of the following energy sources
(a) Hydroelectric power
19.Mention the river where each the following dams is located
(a) Aswan High Dam
(b) Akosombo dam
(c) Kariba dam
(d) H.F Verwoerd dam
(e) Kabora Bassa dam
(f) Kainji dam
(g) Mtera dam
(h) Nyumba ya mungu dam
(i) Kidatu Dam
20.Outline the four factors that led to the development of biogas in Tanzania
21.Show the impact of fuel wood exploitation on the environment
22.Biogas exploitation is one way of waste management. Explain how this is true
23.Identify for pints to justify (support) that Tanzania has high HEP potential
24.Show the factors hindering exploitation of HEP in Tanzania
25.Suggest the ways that Tanzania can use in harnessing its HEP