Etude stratigraphique, pétrographique et diagénétique des grès d ...

tel-00534181, version 1 - 9 Nov 2010
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Chapter I
Figure 6. (a) Schematic map of Africa showing the
major structures of the Central African Rift System
(CARS) and the East African Rift System (EARS). (b)
Distribution of surface and subsurface Cretaceous
siliciclastic formations in central (Sudan) and eastern
(Ethiopia, Kenya) Africa (from Vail, 1974;
Beauchamp, 1988). Exploration wells drilled in the
Anza Rift, showing occurrences of Cretaceous
marine and non-marine sediments, are indicated
(from Morley et al., 1999b). (c) Schematic map showing
the distribution of Cretaceous(?) to
Paleogene-Neogene rift basins in south Sudan and
northern-central Kenya. The Loperot-1 well, drilled
in the Lokichar Basin, and the Eliye Springs well,
drilled in the Turkana/Lothidok Basin, respectively,
are indicated (modified from Wescott et al., 1999;
Ebinger and Ibrahim, 1994; Tiercelin et al., 2004).
Figure 7. Regional geology of the north, northwest
and central parts of the Kenya Rift, showing the
major faults and the metamorphic, volcanic and
sedimentary terrains (compiled from Geological
Map of Kenya, 1987; Walsh and Dodson, 1969;
Wescott et al., 1999). The different “Turkana Grits”
formations (Cretaceous(?)-Paleogene): Lapur
Sandstone Fm., Muruanachok Sandstone Fm.,
Lokichar/Lothidok Sandstones, Lariu Sandstones,
and Mount Porr Sandstones are indicated. The
Loperot-1 and Eliye Springs-1 exploration wells
drilled by Shell E & P Kenya B.V., and the seismic
lines acquired by Amoco (TVK-7 and TVK-10) are
shown.
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