The study area  is located in the Eastern edge of “Lower Tagus Basin”, in the Center Southern Portugal (Alto Alentejo). In this region, the main variscan tectonic structure have an WNW-ESE, NE-SW and NNW- SSE orientations, similar to the fault directions affecting the Cenozoic deposits, that. in general, are responsable for the outcrop in the middle of Cenozoic sediments of small Palaeozoic Ossa-Morena Zone, suggesting its reactivation. The faults, in the borders between the substract and the Cenozoic sediments points out to the rising of the Palaeozoic rocks during the Cenozoic.