油气生成、运移模拟实验探讨

本文选用低成熟烃源岩,采取人工热解生成油气及适当控制石油运移的方法,模拟了4个地史热演化阶段(低熟、成熟、高熟、过熟)中油气的生成演化过程。试验中把热解生成烃适当分成排出烃和滞留烃,分别对应于地质体中油气经初次运移进入储层的量和滞留于母岩并同母岩一同继续演化的量。从未熟到过成熟阶段将油气的生成分成4个连续演化阶段,运移分成3个集中阶段,即用多阶段生成、集中运移模拟地质体中油气边生边运的地质过程,得到了不同演化阶段不同运移效率下储层中可能的油气分布。

AN APPROACH TO THE SIMULATION EXPERIMENT OF HYDROCARBON GENERATION AND MIGRATION

In this paper, the process of hydrocarbon generation and evolution in the four thermal evolutionary stages (low mature, mature, high mature, overmature) of geohistory is simulated by selecting low mature hydrocarbon source rocks and using the method in which hydrocarbons are generated from artificial pyrolysis and petroleum migration is controlled properly. In the experiment, the hydrocarbons generated from pyrolysis are appropriately classified as drained and occluded hydrocarbons which correspond to the amount of hydrocarbons in geologic body entering reservoirs by primary migration and the amount occluded in parent rocks and evolving continuously together with parent rocks, respectively. The generation of hydrocarbons can be divided into four stages with continuous evolution, from unmature to overmature stages, and the migration into three concentrated stages; that is, the geological process of geologic body during which hydrocarbons generate and migrate simultaneously is simulated as multistage generation and concentrated migration, Thus, the possible distribution of hydrocarbons in reservoirs in different evolutionary stages and under different migration efficiency can be obtained.