潜山圈闭成藏特征及地质风险评价——以渤海湾盆地济阳坳陷为例

渤海湾盆地济阳坳陷潜山圈闭主要有断块、残丘和内幕潜山3种类型,不同类型的潜山圈闭具有不同的成藏特征,控制成藏的地质因素所发挥的作用不同。针对保存、运聚配套、圈闭、储层条件等4项地质条件及圈闭可靠程度共5项评价指标对圈闭地质风险进行综合评价,采用“5项条件评价值加权求和”的方法求取地质风险系数,建立潜山圈闭地质风险评价分级标准。对济阳坳陷潜山圈闭的评价结果表明,所建立的潜山圈闭地质风险评价方法和评价标准,能反映探区地质特点和勘探实际情况。

RESERVOIR FORMING CHARACTERISTICS AND GEOLOGIC RISK EVALUATION OF THE BURIED HILL TRAPS IN THE JIYANG DEPRESSION OF THE BOHAIWAN BASIN

There are mainly three types of the buried hill traps in the Jiyang Depression of the Bohai wan Basin.They are fault block,hammock and internal types of buried hill trap with different reservoir for-(ming) chacteristics.Different geologic conditions play a different role on the buried hill trap reservoir for-ming.When five evaluation conditions and weight coefficient of each gelogical element were researched,the difference and the actual features of Jiyang depression should be fully reflected.Hierarchical evaluation criteria may be established by applying the methods of drilling success ratio hierarchy,cumulative probability curve and geologic analysis for the geological elements of the trap.The application presents that the established evaluation methods and criteria for the geologic risk in a buried hill trap can reflect the geological characteristics and actual exploration situation of the exploration area.