PRIMARY STUDY ON THE EFFECTS OF DEEP-SOURCED FLUID’S MOVEMENT ON HYDROCARBON MIGRATION

In recent years,research on deep-sourced fluid has become a hotspot in geology.A lot of evidences about the movements of deep-sourced fluid have been found in many depositional basins.When this fluid comes into existence in basins,it will produce great impacts on geological structures,evolution of rocks,fluid movements and accumulation of oil and gas.As a part of them,the oil and gas migration is not of exception.Researches show that deep-sourced fluid exists in supercritical state in mantle and lower crust of the earth.It can extract and enrich dispersive organic matters in sediments because of its high dissolving and diffusing capacity,and transport them.Then it can promote kerogen to generate hydrocarbon with hydrogen added,thus it can promote source rocks to expel hydrocarbons.In addition,the physical and chemical reactions between deep-sourced fluid and surrounding rocks greatly improve the porosity and permeability of resevoir,which contributes a lot to secondary migration of oil and gas.Besides,deep-sourced fluid can melt the rocks in crust to form igneous rock,and this rock can prevent the oil and gas migration to form reservoir.