3D seismic characterisation of an array of blind normal faults in the Levant Basin, Eastern Mediterranean

Abstract

The geometry, throw distribution and kinematics of an array of blind normal faults were investigated using a high resolution 3D seismic dataset located in the Levant Basin, offshore Israel, to establish criteria allowing true blind faults to be distinguished from minor synsedimentary faults. A detailed analysis of throw distribution on the fault planes shows that the displacement exhibits a crudely concentric pattern about a maximum region located centrally on a fault plane, as expected for ideal blind faults. However, vertical displacement profiles do not exhibit classical linear or triangular profiles but are mostly flat-topped or hybrid in type. Comparison of unrestricted blind faults to those that interacted with a mechanical boundary or another structure suggests that such interactions significantly modify the throw spatial distribution on a fault plane. To distinguish small synsedimentary faults from blind faults, we use a combination of three criteria to assess whether a fault grew by blind propagation: (1) plunging upper-tip region and complementary pattern in the throw contours, (2) presence of upper-tip propagation fold, and (3) absence of stratigraphic evidence that the fault interacted with the free surface.