古水动力模拟在塔里木盆地中的应用

APPLICATION OF PALAEOHYDRODYNAMIC MODELING TO TARIM BASIN

康志宏 康艳芳 邓林 王英民 虎北辰 张鹏德 杨宏 黄地龙

Kang Zhihong Kang Yanfang Deng Lin Wang Yinmin Hu Beichen Zhang Pengde Yang Hong Huang Dilong

根据非均匀各向异性地层的非稳定的地下水流动模型,采用有限差分法求解,可以定量判断油气运移的方向及强度.塔里木盆地存在海西早期、晚期及喜马拉雅期个主生烃期,模拟结果表明:海西早期,古水流向四周发散,塔中隆起、沙雅隆起及其南部和东部地区为油气有利聚集区,同时由于该期构造运动较强,古油藏暴露地表,油气藏以破坏为主;海西晚期,油气运移指向塔中和塔北隆起,主要聚集区为塔中;喜马拉雅期,地表降水和泄水作用极为强烈,油气藏不同程度地遭受破坏作用,油气藏充满程度下降、压力系统改变.

According to geologic model of unsteady groundwater flow in heterogeneous medium and adopting the finite difference solution,the direction and strength of oil gas migration can be quantified.Tarim Basin had three main oil gas generating phases including the early Hercynian,the late Hercynian and the Himalayan phases,Modeling result suggests that,in the early Hercynain,groundwater flew from the source depression to the around areas.Tazhong,Shaya Uplifts and the south and east of Shaya Uplift are favourable for oil gas migration.As the early Hercynian movement was very strong,fossil oil pools were exposed on surface and mainly denudated;in the later Hercynian,the oil gas migrated to Tazhong and Tabei Uplifts,accumulated in Tazhong;in the Himalayan stage,because of intense surface waterfall and draining,fissil oil pools were distoried;the fullness of the pools decreased ,and pressure system was changed.

10.11743/ogg20010319