Tertiary basins of Spain: Alpine tectonic framework of south-western Duero basin

The tectonic activity in the south-western area of the Spanish Northern Meseta (Ciudad Rodrigo and Duero basins) during most of the Tertiary was determined by u transpressive regime that reactivated Hercynian to Late-Hercynian faults. The record of the Alpine Orogeny is complex because the sedimentary record indicates a compresive regime in the sour e areas coeval with the extensionall to transpresive regime indicated by normal or strike-slip faults. This duality is due 10 the geotectonics position of this area between two compressive areas, the Cantabrian Range and the Central System, and the extensional Atlantic margin.