东海西湖凹陷地下流体动力场研究

以油气成藏动力学理论为指导,在综合分析钻探、地球物理、分析测试、地质地化资料的基础上,采用静态描述和动态模拟相结合的方法,对东海西湖凹陷的温度场,压力场、流体势能场及其对油气运聚成藏的影响进行了系统研究。研究表明,研究区不同区域的单井温度与压力场的变化存在一定的规律性;剖面现今流体压力自上而下依次可分为正常压力、弱超压和强超压三大系统,断层对超压的分布具重要的控制作用,超压场演化可分为原始积累、部分释放和再积累三大阶段,超压系统为半封闭型,欠压实和新生流体是其增压的两大主导机制;剖面流体势呈“双层”结构,流体势分布的相对低值区是油气聚集的有利部位。

STUDY ON UNDERGROUND FLUID DYNAMICAL FIELDS OF XIHU SAG,EAST CHINA SEA

Under the guidance of the theory of pool-forming dynamics,the temperature and pressure fields,fluid potential energy fields and its influence on hydrocarbon migration and accumulation are studied systematically by analyzing the data of well.geophysics,testing,geology and geochemistry and using the technique of dynamic modeling combined with static statement. The temperature and pressure fields in wells varied with a certain rule. The current pressrue system in profiles consists of normal pressure,low overpressure and hard overpressure from top to bottom,which were controlled mainly by the distribution of faults obviously. The evolution of overpressure fields can be divided into three stages:initial accumulation,partial pressure expulsion and re-accumulation. The overpressure systems belong to the type of semi-enclosed,which were generated mainly from strata undercompaction and hydrocarbon generation. The fluid potential in profiles presented as double-layer type. The areas being a relatively low potential are the favorable places for hydrocarbon accumulation.