New Insights from Gravity Data on the Geodynamic Evolution of Northern African Passive Margin, Case Study of the Tajerouine Area (Northern Tunisian Atlas)

Abstract

In Northern Tunisia, geological structuring is very diverse. This diversification is due to its localization, which is situated within the convergence zone between Africa and Eurasia plates. This situation allows to a complicated geodynamic evolution from Permian Tethy’s opening to the quaternary. Our study area is a key zone because we find several structures (Triassic extrusions, reefs, folds, grabens). The Surface studies (structural, sedimentology, etc.) leave controversies and many directions are only indicated as supposed faults. Thus, to understand geodynamic evolution is very important for petroleum and mining exploration. For this purpose geophysical method, which corresponds to a gravity data interpretation, is used to explore the subsurface structures. In this study, different techniques (regionalresidual separation, Horizontal gradient magnitude, upward continuation, Euler DE convolution) were applied to the gravity anomaly map. The results obtained allowed to draw up a structural map showing faults system responsible for structuring the study area. The obtained structural map is consistent with several faults already identified in previous studies and shows new directions. This map leads to better understanding the geological structures and the geodynamic evolution of the region and is a very useful document to guide future mining and hydrocarbons operations research.