金马—聚源地区沙溪庙组油气勘探前景研究

PROSPECTS FOR EXPLORING FOR OIL AND GAS IN SHAXIMIAO FORMATION AT JINMA-JUYUAN REGION

在金马—鸭子河地区油气勘探现状分析的基础上 ,对该区的燕山期构造演化、地震相展布以及保存条件等油气成藏条件进行了研究 ,提出了聚源—崇火燕山中晚期古隆起的存在 ,以及该区沙溪庙组油气成藏的四个有利条件为 :①燕山中晚期适时古隆起形成的早期圈闭 ;②充足的须家河组气源及良好的扇三角洲储盖组合 ;③构造、岩性对早期圈闭的保存作用 ;④喜山期断裂、裂缝对致密储层储集性的改善作用。由此最终确立了聚源—崇火地区沙溪庙组油气成藏的主控因素为燕山中晚期适时古隆起形成的早期圈闭 ,为一岩性— (古 )构造复合圈闭类型。

Through studying the factors controlling reservoir formation,such as tectonic evolution during Yanshan Epoch,seismic facies distribution and hydrocarbon-preserved conditions,etc.,at Jinma-Yazihe region on the basis of analyzing the current situation of oil and gas exploration at this region,it is put forward that the palaeohigh had occurred in Middle-Late Yanshan Epoch at Juyuan-Chonghuo region and there were four beneficial factors of oil and gas reservoir formation in Shaximiao Formation at the region,i.e.① the early traps timely formed with the palaeohigh in Middle-Late Yanshan Epoch;② an abundant gas source in Xujiahe Formation and a fair reservoir-seal assemblage of fan delta;③ structural and lithological preservation function to the early traps;and ④ an improvement on tight reservoirs by the faults and fractures occurred during Himalayan Epoch.For this reason,it is determined finally that the main factor controlling oil and gas reservoir formation in Shaximiao Formation at Juyuan-Chonghuo region is the early trap timely formed with the palaeohigh in Middle-Late Yanshan Epoch,so it is a lithologic-(palaeo) structural combination trap.