油气二次运移通道稳定性及其成因机制

烃源岩生成的油气要经过一定距离的二次运移后才能在有效的圈闭中聚集成藏，因此油气二次运移的过程对
于油气最终聚集率有很大的影响。原油的二次运移过程可分为活塞式和优势式，天然气二次运移是一种由活塞式和
优势式两种基本运移方式组成的断续式运移。二次运移模式的不同导致了油气运移路径的稳定性存在差异，采用染
色煤油和氮气分别进行二次运移过程物理模拟实验，通过多次充注的方式探讨油气二次运移通道稳定性，并结合油气
水物性特征差异及其与孔隙岩石的关系分析了其成因机制。认为原油二次运移过程中形成比较稳定的运移通道，运
移效率较高；天然气二次运移过程中形成一种动态的相对稳定的运移通道，运移散失量较大。

Stability and Formation Mechanism Analysis of Secondary Migration Pathway of Hydrocarbon

Abstract：In order to accumulate in effective trap，hydrocarbon generated form source rocks has to go through a certain
distance of secondary migration，therefore the process of hydrocarbon secondary migration has a great influence on ultimate
hydrocarbon accumulation rate. The secondary migration process of crude oil can be divided into two types：piston pattern and
advantage pattern；the secondary migration of gas is an intermittent migration process composed of piston pattern and advantage
pattern. The difference of secondary migration pattern leads to the differences in the migration pathway stability between oil
and gas. This study used dyed kerosene and nitrogen to conduct physical simulation experiment of secondary migration process
respectively，and discussed secondary migration pathway stability of oil and gas through way of more than one filling，and
analyzed its formation mechanism in view of the different physical characteristics between oil，gas and water and the relation of
the difference to porosity of reservoir rock. In our opinion，a fairly stable migration pathway could be formed in the process of
oil secondary migration，so its transport efficiency is higher；natural gas forms a relatively stable dynamic migration pathway
in the process of secondary migration，the loss amount while migrating is larger.