Oil and gas exploration domains on the southern slope of Central Tarim Uplift, Tarim Basin

Based on the analysis of seismic facies characteristics, combined with the relationship between sedimentary facies and TOC content of the main wells, we suggested that the sedimentary facies of the Middle-Lower Cambrian on the southern slope of Central Tarim Uplift is the same as those of the Central Tarim Uplift. The main deposits there are the evaporative platform in salt (mud) and the restricted dolomite platform facies. The hydrocarbon generation potential in the study area is worse than that of the dark grey and black mudstone (shale) developed in a deep water and under-compensated environment on the Manjiaer Slope. Also, we analyzed the accumulation characteristics of the main oil and gas reservoirs, and the reasons why nearly 20 wells in the buried hill area on the southern slope failed to produce commercial oil or gas. It was pointed out that faults controlled storage, reservoir and enrichment. The Ordovician oil and gas enrichment areas in the Central Tarim Uplift are mainly the intersection of the NW and NE fractures, the Central Tarim no. I "Y" type fault zone, the vicinity of NE strike-slip faults (< 1 km), the oil source communicating faults with a big fault throw (T₈¹), and the graben-tensional fracture zone of NE strike-slips. It was pointed out that exploration of buried hills on the southern slope of Central Tarim should change from the high trap position of buried hills to the high trap position of dolomite buried hills near the main fault. The high positions of large anticlinal structural traps close to oil source with source communicating fractures and favorable reservoir and cap assemblage are the pre-salt hydrocarbon enrichment areas in Cambrian.