RELATIONSHIP BETWEEN HYDROGEOLOGY FEATURES AND HYDROCARBON ACCUMULATION IN WUERXUN SAG, HAILAER BASIN

Groundwater is an important carrier of hydrocarbon migration in sedimentary basins.Hydrogeological characteristics can control or influence reservoir boundary.On the basis of classifying water-bearing rock series,combining hydrodynamic field with hydrochemical field,the hydrogeological conditions of main water-bearing rock series have been studied in the Wuerxun Sag of the Hailaer Basin.It is divided into 3 different types of hydrogeological zones: a)actively alternating—oxidation zone,which is highly open and is unfavorable for oil and gas accumulation;b)slowly alternating—weak reduction zone,which is more favorable for reservoir formation;c)alternation blocked—reduction zone,which is closed in high degree and is conducive for reservoir formation,hence is the most favorable target area for exploration.