Basin Evolution and Geochemical Modeling
Mesozoic sedimentology and sequence stratigraphy of North Africa
Research by Dr Ian Carr
A synthesis of the sedimentology and sequence stratigraphy of the Mesozoic succession of North Africa has been undertaken. This study has used the vast amount of literature available to attempt to construct a unifying stratigraphic framework for North Africa. Many detailed local studies exist, but few regional studies. Local studies often illustrate the difficulty in correlating successions in close proximity, so this regional study was quite ambitious. In particular, the complex tectonic history of the region during the Mesozoic made this a difficult task, with diachronous rifting causing uplift and downthrow of different areas at different times.
In order to achieve the objectives of the study, two chronostratigraphic correlation panels have been constructed at roughly right angles to each other across North Africa, in WNW-ESE and NNW-SSE orientations. The panels illustrate the way in which sedimentology and hydrocarbon geology varies across the continent through time. The Mesozoic succession is divided into two second-order sequences
NA 6, Early Triassic to Middle Cretaceous, and;
NA 7, Middle to Late Cretaceous
As with the Palaeozoic study, sequence boundaries, maximum flooding surfaces and systems tracts have been defined for the sequences. Palaeogeographic reconstructions for the North African region from the Triassic to the Cretaceous have been generated, and a sea-level curve based on the panels and palaeogeographic reconstructions compared to other published sea-level curves. It is hoped that this regional study will be helpful in separating local tectonic effects from regional to global relative sea-level changes. This could provide a useful framework for future third-order studies.