Tectono-sedimentary Setting of Maastrichtian Deposits along NW-SE Transect in Fars Area, SE Zagros

Late Cretaceous in Zagros encompasses regional tectonics and caused foreland basin to form in northeast of the Arabian Plate. Salt tectonics is also locally affected this area. One of the time periods that can better picture this tectono-sedimentary evolution is Maastrichtian. In order to investigate this evolution in the Maastrichtian time, a regional cross-section was made inthe Fars outcrops and wells. A sedimentological study and sequence stratigraphy have been accomplished along this transect. Maastrichtian deposits consist of the upper part of the Gurpi and the Tarbur formations in the studied transect. Based onsedimentological investigation, 14microfacies have been identified. This microfacies were deposited in 4microfacies belt including tidal flat, restricted and open lagoon, reef and open marine in a shelf carbonate platform. Based on sequence stratigraphic studies, 3 sedimentary sequences were identified in the studied interval. Correlation along the transect revealed that the Maastrichtian deposits occurred on the forebulge of Zagros foreland basin. It is also concluded that the fore-buldge shows a nearly smooth topography and thus accommodation space is homogeneous. Hence the thickness of the Maastrichtian deposits does not vary so much along this transect. Thickness anomaly in Namak-dehkuyeh occurs as a result of salt structure which decreased accommodation space.