Post-salt trapping mechanism of south-east Pre-Caspian and its application to petroleum exploration

摘要

The Kungurian saliferous sediments of the Pre-Caspian sedimentary basin represented by thick stratum of rock salt with interlayered lenses of anhydrites, terrigenous and carbonate rocks. Initial thickness of these sediments estimated as 4000–4500?m at the center of the depression and 1000–2000?m on the edges of the basin. The processes of halokinesis led to formation of more than 1200 salt dome structures represented by salt diapirs and walls, ridges and salt pillows. Number of salt dome related structures of Mesozoic clastic deposits revealed by seismic exploration carried out in 70–90′s of last century are quite common on the south-eastern part of the Pre-Caspian Sedimentary basin. Most of hydrocarbon pools in post-salt clastic rocks have been discovered on fault-related anticline prospects which are derived from salt tectonics morphologically variable (Munyithya et al. Petrol Explor Prod Technol 10: 2257–2267. https://doi.org/10.1007/s13202-020-00917-1, 2020). Other potential traps anticipated in the area are stratigraphic traps, pinch-out and unconformity-related traps, trapped by salt domes and walls or by salt overhang, etc.