油气资源评价中成因法分析与运聚系数取值模型研究

Valuation Model of the Migration-Accumulation Coefficient in the Genetic Method for Assessment of Oil and Gas Resources

成因法是油气资源评价中常用的方法,能较好地体现含油气盆地的生烃、排烃、运聚等过程,具有明确的地质意义,可用来计算油气资源量的“上限值”。其中运聚系数取值是成因法计算的重难点,因此有必要建立一个简单有效并能体现出成因法计算特点的运聚系数取值模型。本文从成因法的自身特点出发,分析了目前运聚系数取值存在的问题,初步建立了运聚系数取值模型。该模型将计算过程分为排烃过程、运移过程、聚集过程、储存过程、破坏过程、资源比例过程这6个过程,并分别设立了6个过程中各项参数的取值依据。最后通过2个刻度区的实例验证,证明该取值模型准确度较高,在中-低勘探程度地区适用性较高,在高勘探程度地区适用性中等。

The genetic method is commonly used in assessment of oil and gas resources,which can well describe the processes of hydrocarbon generation,hydrocarbon expulsion,hydrocarbon migration and accumulation in basins.It has definite geological implications and can be used to calculate the“upper limit”of oil and gas resources.In this method,the valuation of the migration-accumulation coefficient is a key and difficult point.Therefore,it is necessary to establish a simple and effective model to deal with this issue,which can reflect the characteristics of the genetic method.Based on the features of this method,this paper analyzes the existing problems in the current valuation of the migration-accumulation coefficient,and preliminarily establishes a model for this end.This model divides the valuation process into six portions:hydrocarbon expulsion,migration,accumulation,storage,destruction and resource proportion,and sets up the valuation basis for each parameter in the six portions,respectively.At last,the model is proved to be accurate by two calibrated areas,showing the applicability of the model is high in the areas of medium-low degree of exploration,and moderate in the areas of high degree of exploration.