Bandora, Theophile

BOUROULLEC, JL

Coussement, Carine

MONDEGUER, A

REHAULT, JP

ROLET, J

TIERCELIN, JJ

The Lake Tanganyika trough derives from the distension of a late precambrian stabilized craton. The present structure of the trough is the result of a regional NW-SE to WNW-ESE extension direction which prevails since the Oligocene times, and is illustrated by seven contiguous half-grabens separated by transverse thresholds. These relay zones correspond to horst structures, which more or less resisted the general subsidence of the basement. These internal structures strongly influence the sub-lacustrine topography.

Today, the Lake Tanganyika trough is divided into three basins, separated by two major relay zones, forming bathymetric shoals which are thought to reduce hydrologic and sedimentary circulations within the lake.

The structural observations, presented here, include reinterpretation of seismical profiles of the GEORIFT Project (Elf-Aquitaine) and of MSS LANDSAT scenes. The northern end of the trough (BOUROULLEC, 1990) shows a obvious half-graben symmetry, with very well developed border scarps and looking eastward tilted blocks to the west.

This part of the trough is structurally controlled by N-S to NNE-SSW accidents (showing important vertical offset). However NW-SE structural influence occurs south of Uvira, and illustrates thus the role of transverse zones (type TRM) in the recent evolution sketch of the East African Rift System.

The South Tanganyika troughs complex (MONDEGUER, 1991) is determined by two main structural directions: an N 140 direction represented by the southern end of the Lake Tanganyika trough, and constituting the Mpulungu sub-basin which is structured in westward tilted half-graben; an N 70 direction which corresponds to a wide annexe faults zone, running westward from the Mpulungu sub-basin and comprising the Mweru and Mweru Wantipa troughs. Each of these structures, developed in an extensional background, is associated with dextral (Mpulungu sub-basin) or strike-slip movements (Mweru-Mweru Wantipa fault zone)

Ghent University Academic Bibliography

Structure and different kinematic development faults along the Lake Tanganyika rift-valley (East-African Rift System)

STRUCTURE AND DIFFERENT KINEMATIC DEVELOPMENT FAULTS ALONG THE LAKE TANGANYIKA RIFT-VALLEY (EAST-AFRICAN RIFT SYSTEM).

STRUCTURE AND DIFFERENT KINEMATIC DEVELOPMENT FAULTS ALONG THE LAKE TANGANYIKA RIFT-VALLEY (EAST-AFRICAN RIFT SYSTEM).

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Ghent University Academic Bibliography