伊宁凹陷古地温恢复与热演化史研究

A research on the paleotemperature recovery and thermal evolution history of the Yining subbasin,Xinjiang,China

应用包裹体测温和Easy-Ro方法恢复了伊宁凹陷的古地温演化史,结果表明伊宁凹陷晚二叠世的地温梯度约为40℃/km,以后经过两次波动(分别对应于K1和E1两次构造运动)逐渐减小到现今的24℃/km。上二叠统烃源岩热演化程度主要受古地温控制,主生油期在中晚三叠世。印支期及其以前形成的圈闭,是二叠系油气聚集的主要场所。

This paper recovers the paleotemperature evolution history of the Yining sub-basin based on the thermometric data of the secondary fluid inclusions in quartz from Well Ning 3 and by Easy-Ro method used in multiple wells. The result shows that the geothermal gradient of the Yining sub basin in l.ate Permian was 40℃/km, then it experienced two fluctuations （in K1 and E1 structural movements respondingly） and decreased to the present 24℃/kin. This paper also recovers the thermal evolution history of the Yining sub-basin by basin modeling and combining with the thermal evolution features of source rocks. The evolution history suggests that the thermal evolution degree in Upper Permian was mainly controlled by paleotemperature, and the oil generating period was in Middle and Late Triassic. Traps formed before Indo-Chinese epoch was the principle hydrocarbon accumulation of Permian.