Distribution of mantle-derived CO2 gas reservoir and its relationship with basement faults in Songliao Basin, China

Based on the seismic interpretation and the analysis of 11 typical mantle-derived CO2 gas reservoirs, the distribution of these CO2 gas reservoirs and its relationship with basement faults in the Songliao Basin are analyzed deeply. Vertically, the mantle-derived CO2 gas reservoirs are distributed mainly in K1yc volcanic rocks and in K1q3+4 and K2qn2+3 siliciclastic rocks. The mantle-derived CO2 is migrated mainly through the large-scale, low-angle basin-controlling basement faults. The deep-burial CO2 gas reservoirs in the K1yc Formation are distributed mainly in the steep slope zone and central fault-uplift zone. They are controlled by the large-scale boundary and central basement faults (I-BFs) which were active during the syn-rift stage and directly connect with the deep heat flow diapirs or intrusions. The shallow-burial CO2 gas reservoirs in the K1q3+4 and K2qn2+3 Formations are mainly located in the inversion structure belts that are controlled by the inversion of basement faults (I-II-III-BFs) being active in structural inversion stage.