南海琼东南高压盆地压力结构与油气成藏关系

Pressure structure and relationship with hydrocarbon accumulation in Nanhai Qiongdongnan high-pressure basin

南海琼东南盆地为典型的高温超压盆地,在中深层高温超压地层中发育多个大型勘探目标,是中国南海勘探主战场.琼东南盆地存在多种超压成因,使得不同构造位置的压力结构不同,不同的压力结构其压力成因存在差异,并且压力结构与油气的成藏也具有非常密切的关系,而且地层压力结构与钻井安全息息相关.为了提高压力预测精度和钻井安全,研究琼东南高压盆地压力结构与油气成藏关系是十分有意义的.快速沉积的欠压实泥岩排水不畅是超压的主要成因,同时还存在断裂系统泄压、大型沉积体疏导泄压和侧向砂体传递增压等多种成因.本文首先总结不同位置的压力结构,其次分析不同压力结构的成因,最后在超压与油气聚集分析的基础上,总结超压与油气聚集成藏的关系,分析认为崖城凸起砂体泄压型低压带和大崖城区异常高压带是琼东南盆地最有利的勘探区带.

The Qiongdongnan basin of the south China sea is a typical HTHP basin,in HTHP formation in the development of several large exploration targets,is the main battlefield of the South China Sea exploration.There are many cause overpressure,make different tectonic position of pressure structure,different structures of the pressure stress difference and pressure structure and oil and gas accumulation also has a very close relationship,but the formation pressure structure and drilling safety are closely related.In order to improve the prediction accuracy of pressure and drilling safety.The structure and pressure in the Qiongdongnan basin research of high pressure gas accumulation relationship is very significant.The rapid deposition of uncompacted mudstone causes the high-pressure,but also the existence of fracture system pressure relief,large deposits of relief and other grooming transfer booster causes pressure and lateral pressure of sand.This paper first summarizes the different structure the position,followed by the analysis of causes of different pressure structure,finally gathered on the base of analyzing the overpressure and hydrocarbon accumulation,the relationship between overpressure and hydrocarbon analysis summary,think of Yacheng Sand pressure relief type low uplift zone and Yacheng abnormal pressure zone of Qiongdongnan basin is the most favorable exploration zone.