低输导动力条件下天然气运移效率实验模拟

摘要

浮力是油气运移的主要输导动力之一.孔隙空间是主要的输导通道.在输导动力低的情况下,相对低渗透储层(阻流层)对油气运移效率的影响程度增大.结合鄂尔多斯盆地苏里格气田地质条件,采用物理模拟和侵入渗流数值模拟,研究了低输导动力条件下油气运移输导效率影响因素.认识到构造幅度较低时输导动力变弱,储层非均质性高、物性较差容易形成阻流层,阻流层分散天然气资源,成为影响输导能力的瓶颈.提出苏里格气田生烃面积虽大,但运移效率低是天然气储量大但资源丰度低的主要原因.%Buoyancy is one of the main driving forces during oil and gas migration, and pore space is the main migration pathway.Low permeability reservoir has distinct influence on migration under low driving force.The relationship between driving force and pathway by means of physical simulation arid numerical simulation based on the theory of invasion percolation are analyzed, and numerical simulation for Sulige gas field are made.As a conclusion, low amplitude structure make low driving force, heterogeneity and low permeability reservoir disperse natural gas accumulation.Though Sulige gas field has extensive hydrocarbon generation, low migration efficiency is the main reason that the Sulige gas field has large reserves but low reserves abundance.