Fault pattern delineation and structural interpretation of the Gafsa trough (onshore central Tunisia) using gravity data

摘要

The purpose of this investigation was to identify subsurface lineaments in Gafsa trough (onshore central Tunisia) after gravity data analysis. The Bouguer and residual gravity maps show a gravity values decrease from west to east associated with subsidence variation and confirmed by a regional seismic reflection profile. The deep structural map of the study area is elaborated after the application of two methods: (1) the automatic lineament tracing after horizontal gravity gradient and (2) 3D Euler method. The dominant trends show approximately NW-SE, E-W, and NE-SW directions. Some of these trends are well correlated with the major faults systems. We can qualify the deep structuration model as a mosaic of quadratic blocks bounded by significant deep flower fault corridors. The elaborated structural map of the study area constitutes also a useful document for rationalizing the future petroleum exploration in the Gafsa trough.