四川盆地上三叠统碎屑岩油气成藏年代分析

Research on the Geochronology of Forming the Gas Pools of Upper Triassic in Sichuan Basin

通过烃源岩生排烃史、包裹体均一温度定年、自生矿物K-Ar定年等方法对川西、川中、川南上三叠统气藏成藏年代进行分析,确定四川盆地上三叠统气藏成藏期的早期、中期和晚期,其中中期为最重要的成藏期,早期与中期(印支期与燕山期)为烃源岩生烃成藏期,晚期(喜山期)为油气调整成藏期。区域差异表现为,川西地区成藏时间相对最早,稍晚为川南地区,川中地区成藏时间最晚。

By analyzing the period of hydrocarbon generating and discharging of source rocks, researching K - Are isotopic dating and examining the homogenization temperatures of inclusions, and so on, we divide the oil and gas accumulation periods in the Upper Triassic in Sichuan Basin into three stages. Amount of hydrocarbon are generated during the early stage and middle stage （Indosinan and Yanshanian）. The later stage （Himalayan） is the period that the oil reconstructed and reallocated. Regional difference is shown as, accumulation time relative to the west- ern Sichuan region is the first, followed by the middle region, the southern region is relatively late.