Hydrocarbon generation capacity analysis of Carboniferous source rocks in Dishuiquan sag of Junggar Basin

Key words:  Junggar Basin  Dishuiquan sag  Carboniferous  oil-gas source  source rocks  hydrocarbon production potential

Abstract:

Based on the analysis of assay data of cores and outcrop samples, abundance,types of organic matter and evolution of Carboniferous source rocks from Dishuiquan sag were studied. And the hydrocarbon generation ability of Carboniferous source rocks was analyzed based on the characteristics of oil and gas source in peripheral structures of sag. The results show that the source rocks are characterized by high-abundance organic matters, great sedimentary thickness and great hydrocarbon generation ability, which have reached the postmaturity stage till now. Combined with the feature of the structure, the existence of "groove" in swell of southern Dinan and the unsuccessful migration of the oil and gas from northern Dongdaohaizi sag to the Carboniferous of Kelameili gas field for accumulation were presented. Million tons of oil and gas in Kelameili gas field should come from Dishuiquan sag. The oil and gas of Shidong field from both deep and shallow layers are almost the same, which is different from that Shixi field, but the same as the Carboniferous of Kelameili gas field because they both come from Dishuiquan sag. Integrated with paleogeographical distribution and structural evolution of this region, waters in Dishuiquan sag, Sannan sag and northern Dongdaohaizi sag are connected in the depositional stage of the Carboniferous period. Carboniferous hydrocarbon source rocks should have great capacity of hydrocarbon production and fine potential for exploration.