| Geology |
BRIEF GEOLOGY
The sediment ascribed to the Karoo are preserved in Ruhuhu depression which is elongated in north-easterly direction.
The Karoo rocks are continental,dominantly arenaceous sediments.The succession includes sandstones,conglomerates,and sandy,and fine grained siltstones with coal measures in lower part.
The general stratigraphic succession of the songea series was established by Stockley in 1930,He recognized eight stages based on lithology now defined from top to base as follows
K8 Manda beds with Upper Bone Bed
K7 Kingori sandstones
K6 Lower Bone Bed
K5 Ruhuhu beds
K4 Upper coal Measures
K3 Intermidiate mudstones and sandstones
K2 Lower coal Measures
K1 Basal sandstone |
| Recommendation |
RECOMMENDATION
Fossil evidence from reptiles and other vertebrates, from fresh-water lamellibranches and from plants,allow a general correlation with the type of Karoo succession of South Africa.Comparison is strengthened by the presence near the base of deposits of probable glacial orign.
In the neighbor,the most important coalfields in East Africa,the Kitewaka-Mchuchuma and the Ngaka Coal fields.These have been investigated by the geological Survey and the Colonial Development Corporation.The latter have proved coal reserves of not less than 250 million tons.
The Coal measures are of Permian age as are those of Rhodesia and South Africa
Silicification of the sediment is found and have been suggested that this may be related to igneous activity,Around Manda Utrabasic rocks in the form of pipes and dykes of carbonate-rich,kimberlitic material are found intrusive into K7 or lower K8 beds.
|
