德惠断陷有机烃类气与无机CO_2气成藏期研究

A Study on Accumulation Period of Organic Hydrocarbon Gas and Inorganic CO_2 Gas in the Dehui Fault Depression

松辽盆地南部德惠断陷存在着丰富的有机烃类气和无机CO2气资源,应用烃类气与CO2气储集层流体包裹体均一温度实测结果与构造演化史分析相结合,确定营城组烃类气藏是二期成藏,时间分别是泉头组沉积末期(103×106a)和嫩江组沉积期(83×106～76×106a);CO2气藏形成时间存在多解性(98×106a或者是10×106a)。烃类气藏与CO2气藏的成藏方式截然不同,烃类气是缓慢、持续成藏,CO2气伴随着幔源构造运动的发生与构造事件密不可分,是瞬间成藏。营城组天然气藏的成藏序次是,烃类气藏先期形成,CO2气藏后期形成。

There are abundant organic hydrocarbon gas and inorganic CO2 gas resources in Dehui fault depression of southern Songliao basin. Based on the actual homogenization temperature measurement results of fluid inclusion in organic hydrocarbon gas and inorganic CO2 gas reservoirs and in consideration of analysis of the history of tectonic evolution at the same time, there exist two periods of hydrocarbon gas accumulation at the end of Quantou formation （103×10^6 a）and Nenjiang formation （83×10^6 -76×10^6 a）. The formation time of CO2 gas reservoir is controversial （98×10^6a or 10×10^6 a）. The accumulation patterns of hydrocarbon gas and inorganic CO2 gas are significantly different. The former is slow and continuous, the latter is instantaneous and accompanied with the occurrence of mantle- derived tectonic movement, and is closely related to the tectonic events. It is concluded that the inorganic CO2 gas reservoir is accumulated later than the Yingcheng hydrocarbon gas reservoir.