油气运移表征参数优选及运移方式判识

摘要

The change ratio of geochemical parameters was proposed and applied in the Bonan Subsag,Zhanhua Sagto quantitatively identify the migration dynamics and patterns of petroleum in overpressured basins. Based on oil source correlation,migration pathway recognition and pressure distribution,the method of the change ratios of geochemical parameters was selected and calculated to identify the range of overpressure-driven, buoyancy-driven or complex driven oil reservoirs.Migration dynamics,patterns and function boundariesin the process of hydrocarbon migration can be determined. This method can quantitatively characterize and recognize hydrocarbon migration patterns. However, influenced by the changing characteristics of parameters, it is applicable to identify the patterns of hydrocarbon migration for the same origin, the same path and the same period. Affected by differential structural background, hydrocarbon propertiesand migration pathway,the determining boundary of the change ratio of geochemical parameters has differentiation and regional specificityin application.%为定量判识超压盆地中油气运移动力以及油气运移方式,提出了"油气运移参数变化率"的定义,并以沾化凹陷渤南洼陷为例进行了应用与探讨.研究表明,以油源对比、运移路径判识以及压力分布特征分析为基础,通过优选各类运移表征参数,计算"运移参数变化率",可以定量确定超压驱动、浮力驱动以及混合驱动所对应的运移参数变化率范围,从而有效地判识油气运移过程中所具有的运移动力构成、运移方式及其作用边界.此方法较好地解决了油气运移方式的量化表征与判识,受控于参数的变化,该方法适用于同源、同路径和同期次油气运移方式的定量判识.受构造背景、油气性质和运移路径差异的影响,在实际应用的过程中,运移参数变化率的判定界限存在差异,量化标准具有地区特定性.