蓬莱9-1潜山花岗岩油藏成藏时间的裂变径迹热年代学约束

Thermochronologic constraints on hydrocarbon accumulation period of the Penglai 9-1 granite buried-hill oil pool in Bohai,China

油气藏成藏时间的确定一直是石油地质研究领域的难点。该文利用磷灰石裂变径迹测龄及温度-时间热史模拟技术探索了如何精确限定油气藏的成藏时间。从渤海蓬莱9-1潜山花岗岩储层裂缝带和基岩带分别获取2件磷灰石样品,根据磷灰石裂变径迹的长度、年龄和径迹分布,利用AFT Solve软件模拟获得了它们的温度-时间热史轨迹。2件样品相似的温度-时间热史轨迹表明,在3.8-2.6 Ma B.P.期间,由于受石油流体充注的影响,样品发生异常热扰动和温度突变,在3.2 Ma B.P.时期受扰动的温度达到最大。根据受异常热扰动的起始时间,确定蓬莱9-1潜山花岗岩石油充注时间为3.8-2.6 Ma B.P.,油气藏的主成藏期为3.2Ma B.P.。

The research of pool-forming period is Apatite fission track technology and thermal histor accumulation period accurately. Two apatite samp always a difficult subject in petroleum geology. y simulation are used to determine the hydrocarbon les from fissured zone and fresh basement zone in Penglai 9-1 buried-hill in Bohai area are selected to analysis the length, age and distribution of track, then to obtain the thermal history by imitating via AFT Solve software. The results indicate that there is abnormal thermal disturbance because of the hydrocarbon accumulation happened during 3.8- 2.6 Ma B. P.. The unusual temperature turned to be highest when the time is 3.2 Ma. Based on the starting time of the temperature disturbance, 3.8-2.6 Ma B. P. is considered as the hydrocarbon accumulation period of the Penglai 9-1 granite buried-hill oil pool, and the main period is 3.2 Ma B. P..