Characterization of various types of deformation and their corresponding deviatoric stress tensors using microfault analysis

Abstract

Considering an ideally prefractured material, based on Mohr's representation and Bott's model, we define the geometry and the peculiarities of the different theoretical fault domains which are likely to be reactivated under different tectonic regimes. The theoretical striations associated with the different types of deformation are also calculated. The compressive strike-slip, extensive strike-slip, radial extensive and constrictive types of deformation are specified. In the second part of this paper, using Etchecopar's computer-aided method, a quantitative structural analysis of various types of superficial deformation has been carried out in different study areas (southern France, Greece, Spain, Tunisia and Nigeria). The geometry of the microfault domains, as well as the nature of the associated tensors are determined for each type of regional deformation. The problem of the spatial homogeneity of the tensors deduced by the microtectonic analysis within the framework of a particular tectonic phase is also discussed.