【作者】 孙宜朴； 许化政； 王传刚； 杨伟利； 王毅； 伍天洪；

【Author】 Xu Huazheng Wang Chuangang Yang Weili Wang Yi Wu Tianhong Sun Yipu

【机构】 中国石化石油勘探开发研究院；

【摘要】 关于风化壳大气田成因的讨论已持续了十多年。煤系成因说、碳酸盐岩成因说都提供了丰富的地球化学资料,但也留下不少的疑问。最大的疑问是二者都未从地质上提出令人信服的解释。笔者根据风化壳碳酸盐岩样品出现高TOC、高IH、包裹体含油及高频出现的沥青充填现象,推测风化壳曾存在古油藏,进而追踪中隆带西翼构造下倾方向存在高有机质丰度海相生油岩-平凉页岩。中奥陶世平凉期,秦、祁、贺三叉裂谷发育至顶峰,形成大型深水盆地,沉积了厚度大于1000m的以泥页岩、泥质灰岩为主体的深水斜坡相地层,以“L”型沉降带围绕鄂尔多斯古陆分布。在C2-K1的连续埋藏作用中,生成油气并向中隆带运移聚集,在古潜台风化壳圈闭内近水平的往复运动中石油继续向天然气演化,形成大型干气田。更多还原

【Abstract】 It has been lasting for more than ten years about the origin theory of large weathering crust. The coal series origin theory and the carbonate origin theory both provide abundant geochemical data, but there are much doubt about them. The most important doubt is that neither theory provides the compellent geological explanation. According to the high value of TOC, high value of IH, inclusion bearing oil and high frequency existing bitumen filling of carbonate samples of weathering crust, it is presumed that once there is paleo-oil pools in the weathering crust and then there exist high enrich marine oil generation sources, Pingliang shale, in the declining belt of the west central uplift zone. The Qin-Qi-He trige minal rift well develop in the Pingliang age Ordovician and become a large deep-water basin, with more than 1000m thick deep-water slope facies deposition of mudstone and muddy limestone. The declination zone with ’L’ type distributes around the paleo Ordos land. In the C2-K1 successive subsiding, oil and gas generate in the deep-water basin and migrate and accumulate in the central lift zone. During the to and fro migration of oil and gas in the paleo buried platform weathering crust, the large-scale dry-gas field.更多还原