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The northeast Brazilian rift system

Article Abstract:

The rift system located in northeastern Brazil contains chronostratigraphic data relevant to the understanding of the evolution of the South Atlantic basin resulting from the separation of South America and Africa. Rift basins dating from the Early Cretaceous show intracontinental rift systems in three dimension. Such rift systems are governed by the structural framework of the basement rocks. On the other hand, weakness zones preexisting in the upper crust governed the formation of listic normal faults while accomodation zones, transfer faults and other transverse structures were generated according to the structure of the basement rocks.

Brazil

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Geology and geophysics of the Rukwa rift, East Africa

Article Abstract:

The hydrocarbon exploration of the Rukwa rift in East Africa reveals the geological and geophysical data of the region. In the Rukwa rift, as in other continental rift models, the lacustrine sedimentation follows the initial fluvial deposition, which significantly modifies the lacustrine phase. Both Karroo and Tertiary age sediments expand into the Lupa fault zone, attaining the maximum thickness of 3-3.35 km and 7-7.5 km, respectively. The changing displacements on boundary faults on either side of the rift changes the geometry of the Rukwa basin along the strike from southeast to northwest.

Analysis, Sediments (Geology), Africa, East

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Crustal-scale thrusting and origin of the Montreal River monocline - a 35-km-thick cross section of the Midcontinent rift in northern Michigan and Wisconsin

Article Abstract:

The Montreal river monocline, in the south of Lake Superior, is sharply inclined to vertical sedimentary rocks. The rocks are structurally intact and incline southward to from a monocline. The midcontinent rift system is formed after extension due to faulting and uplifting, which occur at 1060 + /-20 Ma. The deformation in the prerift middle and lower crust is the result of crustal thinning.

Lake Superior

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