International Geologiical Congress - Oslo 2008


Search Abstracts

Author Index

Symposia Programmes





GEP-09 Linking petroleum systems and plays to sedimentary basin evolution Part 1


Petroleum assessment of the intrcratonic Taoudeni basin, Mali


Ibrahim Amadou, NTNU (Norway)


The intracratonic Taoudeni Basin is the largest sedimentary basin in NW Africa covering large parts of Mali and neighbouring Mauretania. The basin was formed during the mid-late Proterozoic and subsidence continued through to the mid-Paleozoic when Hercynian deformation and uplift occurred. Up to 6000 m of late Precambrian and Paleozoic sediments are found in the basin. A preliminary phase of drilling in the 1980s penetrated most of the sedimentary succession and two potential petroleum systems, Late Precambrian and Paleozoic, have been defined. The Late Precambrian system has proven source rocks in carbonates (algal stromatolites) and black shales and reservoirs in carbonate and sandstone sequences. The Paleozoic system comprises Silurian-Devonian marine shale source rocks and reservoirs in overlying Devono-Carboniferous sandstones and underlying Cambro-Ordovician sandstones. Potential trapping styles are numerous unconformity traps and large scale Hercynian folds. Problems with petroleum generation modeling in the basin are the thermal effects of Hercynian uplift and erosion and the intrusion of Mesozoic dolerite intrusions. Using a uniform low heat flow, appropriate for intracratonic basins, provisional results indicate that the Paleozoic source rocks may have been only marginally mature prior to Hercynian uplift, whereas the Late Precambrian source rocks were probably overmature prior to uplift. Other scenarios, incorporating the thermal effects of uplift and erosion and igneous intrusions are being investigated. Analogue systems in Arabia and North Africa are being used to estimate the resource potential of the basin.


CD-ROM Produced by X-CD Technologies