ABSTRACT

Paradoxically to the very low seismic activity of the mediterranean Languedoc region in southern France, many references of neotectonic indices in this region are reported in the literature. The critical evaluation of them has allowed to produce a first synthetic and comprehensive compilation of such young, potentially-active tectonic structures, aiming at detecting future research fields. This compilation has revealed that this region has undergone two successive tectonic regimes in Neogene times, shifting from a NW-SE extension to a N-S compression, sometimes between the middle Miocene and the early Pliocene. This shift and the present compressional regime need to be related to the collisional stage between Africa and Western Europe since the late Pliocene. This neotectonic (Quaternary geology) approach is the only reliable means of assessing seismic hazard in regions of very low seismic activity, where most of the few epicentral locations do not clearly correlate with suspected-active major faults.