Bureau of Economic Geology, The University of Texas at Austin (www.beg.utexas.edu).
AAPG Annual Convention, Calgary, Alberta, Canada, June 19–22, 2005
Neogene Salt Tectonics in the Salina Basin, Southern Mexico
The evolution of the Salina basin
was affected by intense salt deformation. The Jurassic autochthonous salt
was mobilized to accommodate successive compressional and extensional
tectonic phases. The compression between the Chortis block and the southern
part of Mexico during the Miocene caused thrusting to propagate northward
through the onshore and shallow offshore parts of the basin. The thick
autochthonous salt was used as detachment for the thin-skin compressional
Suprasalt minibasins locally formed onto the Miocene allochthonous salt, which remobilized to accommodate these depocenters. The upper Miocene to Pleistocene interval is affected by extensional structures such as growth faults, grabens and crestal faults. Local strike slip structures are also observed throughout the study area. The main structural styles observed within this interval consist of expulsion rollovers and large EW-trending, counterregional salt systems, indicating a northward movement of the allochthonous salt forming EW-trending ridges between the suprasalt minibasins.