南海北部高温断陷地温-地压系统特征及其成藏意义分析  

Characteristics of Geotemperature—Geopressure System in Basins with High Geotemperature of Northern South China Sea and Its Significance in Hydrocarbon Accumulation

作　　者：黄艳辉 刘震 郭志峰 武彦 程豪华 

机构地区：[1]中国石油大学地球科学学院油气资源与探测国家重点实验室,北京102249

出　　处：《地质论评》2013年第3期470-478,共9页Geological Review

基　　金：国家"973"计划"南海深水盆地油气资源形成与分布基础性研究"项目(编号2009CB219400);国家"十二五"科技重大专项"南海北部深水区成藏组合评价研究"项目(编号2011ZX05025-002-05)的成果

摘　　要：本文通过南海北部主要盆地钻井测试资料,结合砂岩和泥岩样品的高温水热增压模拟实验分析,综合探讨了南海北部高温环境条件下地层温度和地层压力在纵向上的分布特征。认为南海北部琼东南盆地、珠江口盆地深层高温环境存在"高压型地温—地压系统",地温与地压表现为指数曲线关系。区别于传统意义上的"折线模式",高温断陷地温—地压系统在纵向上表现出一种"非折线模式",具体表现在中浅层为静水型地温—地压系统,地温与地压呈直线关系;中深层为高压型地温—地压系统,地温与地压呈指数曲线关系。在该模式中,深层超压流体具有更强的垂向和侧向充注动力,油气可以沿着断层、裂隙和砂体等输导层垂向或侧向运移到相对更浅、更远的圈闭中聚集成藏。该模式的提出,补充完善了地温—地压系统概念,尤其针对高温断陷盆地的油气勘探研究,能够大幅提高油气资源勘探潜力。Through research of drilling test data in the main basins of northern South China Sea and analysis of aquathermal pressuring experiment under high temperature for sandstone and mudstone sample in the deepwater area of northern South China Sea, this paper comprehensively discusses the vertical distribution characteristics of geotemperature and geopressure under high temperature conditions in the deepwater area of northern South China Sea. The research shows the existence of overpressure geotemperature-geopressure system in high temperature environment of deep layers of Qiongdongnan Basin and Pearl River Mouth Basin in northern South China Sea with exponential relation between geotemperature and geopressure. Different from the traditional ＂broken line mode＂, the geotemperature-geopressure system in basins with high geotemperature exhibits a kind of ＂non broken line mode＂ characterized by the straight line relation between geotemperature and geopressure of normal geotemperature-geopressure system in shallow layers and the exponential relation between geotemperature and geopressure of overpressure geotemperature-geopressure system in deep layers. In this mode the overpressure fluid in deep layers has stronger filling power both vertically and laterally so that oil and gas can migrate to relatively shallower and further traps for accumulation along faults, fractures and sand bodies. The model, that perfects the geotemperature-geopressure system concept, especially for the study of basin of high temperature of the oil and gas exploration, can greatly improve the oil and gas exploration potential.

关 键 词：南海北部 高温盆地 地温-地压系统 指数模式 运聚成藏 

分 类 号：P618.13[天文地球—矿床学]