百色盆地那读组地层压实特征及油气运聚规律

COMPACTION OF THE NADU GROUP IN BAISE BASIN AND ITS RELATIONSHIP WITH THE MIGRATION AND ACCUMULATION OF OIL AND GAS

广西百色盆地第三系始新统那读组,从平面上可以划分为生油凹陷中心区、油气环形聚集带和边界断层控制带。已探明的六个砂岩油气藏主要分布于湖盆北缘山麓洪积相沉积区及东部浅湖相沉积区,总体围绕田东、田阳生油凹陷,呈环带分布。这种分布规律与油气运移息息相关。本文从该组地层的压实特征入手,探讨该区地层压力分布状况、异常压力成因及其与流体运移和油气富集的关系。

Eocene Nadu group,in baise basin,Guangxi autonormous region can be divided areally into central oil generation sag area,ring-like belt for oil and gas accumulation,and marginal fault controlling belt respectively.Six sand- stone petroleum reservoirs discovered already are distributed in the pedimount at the north margin of the lake basin and shallow lake faces area in its eastern part,and are in a ring-like belt with Tiandong and Tianyang oil genera- tion sag as a centre.This distribution is related intimately to the migration of oil and gas.This paper,starting from the compaction of the reservoir for- mation,deals with the distribution of formation pressure in this region,the formation of the abnormally high pressure and its relationship with the mi- gration and accumulation of oil and gas.