Previous work reveals presence of mature sedimentary sequence was derived from Jurassic to lower cretaceous periods in the north part of Lake Malawi which has hydrocarbon reservoir prospects. Existence of thick sedimentary sequence rock could possibly trap hydrocarbon especially in lower Shire valley, northern of Lake Malawi. Presence of large proportion volcanic clasts interbedded with sedimentary rocks transported by rivers present for extensive alluvial plain building enhances prospects(Crossley, 1984). The system also swept mud flows generated during active volcanism while ash was washed away from the basin and deposited at the bottom of the lake (Crossley, 1984).
Maturation is important for hydrocarbon existence …show more content…
Series of faults are present with major faults trending from northwest to Southeast for example Livingstone fault as shown in figure 2.2 and figure 2.5 while others trend west-east. Extensional faults dipping in eastward direction in the northern part the lake lead to asymmetry basins formation (Ebinger, 1989).The horsts present are in north to south orientation and Malawi Rift extends to Urema graben central of Mozambique, with hot springs located along the southern and Western regions(Ebinger, 1989). Figure B.2 shows structures such as normal faults bounding the Western Branch (Soreghan et al., 1999, Scholz, …show more content…
Sequence II depicted by previous lake level underlying an unconformity and sequence III being the oldest and deepest (Crossley, 1984, Scholz, 1995, Soreghan et al., 1999) .
I. Tukuyu-Karonga basin stratigraphy
It is one of the basins in north and northeast of Lake Malawi and is useful in understanding the geology of the area; figure 2.3 shows the stratigraphy of the central, eastern and western region of the basin. Precambrian period contains metamorphic rocks while Neogene age contains muddy sandstone which are overlain by Songwe tuff which are in turn overlain by Karoo and clasts (Crossley, 1984).Quaternary age contains Chitimwe beds overlying Chiwondo bed as shown in figure 2.3.
2.5.2. Geophysical (CHECK