Salt Tectonics in the Sivas Basin (Turkey): 3D Visualization of Minibasins and Salt Diapirs
Callot, Jean-Paul1; Bonnel, Cédric; Ribes, Charlotte; Kergaravat, Charlie; Temiz, Haluk; Salel, jean-Francois; and Ringenbach, Jean-Claude
The Sivas Basin, central Anatolia plateau (Turkey), shows a pronounced salt tectonics activity involving the Early Oligocene Hafik Fm. Despite the quasi complete exposure of the structures, the tectonic evolution of the basin has been so far misunderstood because only envisioned in a context of thrust tectonics. Nevertheless, the basin shows reactivation by the Miocene compression with thrust rooting along the evaporite sole. The core of the basin, a 35x25 km area near the Sivas town, displays several minibasins separated by evaporitic walls, and partially covered by remnant of Miocene gypsum canopies. The minibasins are filled by mid Oligocene to early Miocene clastics (reds silts and fluvial sandstones), marls, and lacustrine to marine limestones, the thickness of which may reach 4 kilometres at outcrop. The stratal architecture along evaporite walls records the progressive downbuilding of the minibasins, showing strong rotation of beds, unconformities and local interaction between evaporites extrusion and sedimentation. Within the basin, the stratal record shows thinning and spectacular angular unconformities which are regionally observed and mark the major phases of basin development. The core of the basin displays typical Wall-and-Basin-Structure (WABS) characteristic of minibasin development above a thick salt layer. The stratigraphic pile record several major phases of allochtonous evaporite canopies development, associated to important rotation of the minibasins. The observed geometries show striking similarities with the seismic data retrieved from the exploration of salt basins, such as the Gulf of Mexico one (see Ringenbach et al., this session).
AAPG Search and Discovery Article #90166©2013 AAPG International Conference & Exhibition, Cartagena, Colombia, 8-11 September 2013