Hydrocarbon-Generating Effectiveness Of Carbonate Source Rock Of Xiagou Formation In Qingxi Sag,Jiuquan Basin

The lower Cretaceous Xiagou Formation of semi deep lake and deep lake facies is dark dolomitic mudstone and argillaceous dolomite in Qingxi Sag,Jiuquan Basin,which has the conditions of forming tight oil reservoir.This thesis focuses on the carbonate-containing source rock of Xiagou Formation,evaluate the tight oil carbonate-containing source rocks and analyze how the carbonate mineral impact on the organic matter abundance and hydrocarbon potential through source rocks collected,Rock-Eval,TOC content,X-ray diffraction,Ro,Extracting,Group component separation and saturated hydrocarbons GC-MS.Using the saturated hydrocarbons GC-MS and carbon isotope analysis of crude oil can separate the crude oil and carry out oil-source rock correlation.Then can confirm the hydrocarbon-generating effectiveness of carbonate-containing source rock of Xiagou Formation in Qingxi sag.The carbonate-containing source rock of Xiagou Formation in Qingxi sag,Jiuquan basin all have high abundance of organic matter,well organic matter type and matured thermal evolution degree.These carbonate-containing source rocks are well source rock.The tight oil can divided into three part and correspond to the different layer of carbonate-containing source rock respectively.This shows the superior carbonate-containing source rocks are the most important condition to tight oil reservoir.