Oil And Gas Resource Evaluation Of Es₄Member And EK Formation,Jiyang Depression

Resource evaluation is an important basis on decision of oil and gas exploration.Although oil and gas exploration effects about Es4-Ek are not as good as Es3's in JiyangDepression,Es4-Ek may be important horizons of the next strategic replacement target.Therefore, for deepening the understanding of hydrocarbon generating quantity, hydrocarbonexpulsion quantity and resource potential of the source rocks of Es4-Ek in Jiyang Depression,we systematically evaluated oil and gas resource of the target zone renewedly.The source rocks of Es4mainly concentrated in the upper Es4. The source rocks of theupper Es4came from saline and brackish water sedimentary environments, the most rocks aregray, dark gray, taupe mudstone and lime mudstone. The source rocks of Ek mainlydistributed in Ek2.The source rocks of the Ek2were mainly a set of semi-deep lake and deeplake facies dark mudstone sedimentary. The most rocks are gray, dark gray mudstone,withtrace amounts of the gray silty sandstone and grey black carbonaceous mudstone.Designing open and closed systems to simulate the primary cracking of organic matterfrom Jiyang Depression into hydrocarbon (oil, gas) and the secondary cracking of crude oilinto gas. Based on the simulation results, the corresponding chemical kinetic model wasestablished and calibrated. Then we applied the model in geology and got hydrocarbongeneration profiles by combining with geological history and thermal history data of eachdepressions. After these, the organic matter abundance and hydrocarbon generation potentialof the study area were recovered by using hydrocarbon profiles. At last, we combined with thesituation of the development of source rocks and hydrocarbon residues to calculate thequantity of hydrocarbon generation and expulsion, and at the same time, determined themigration and accumulation coefficient and the accumulation coefficient for oil and gasresource evaluation based on comprehensive geological conditions of the study area. Theresults demonstrate that: the oil and gas resource was37.66×10⁸t and6.06×1011m3in Es4-Ekof Jiyang Depression, mainly concentrated in upper Sha4member of the Dongying,Zhanhua-Chezhen Depression by the migration and accumulation coefficient; the oil and gasresource was27.61×10⁸⁵5.21×10⁸t and6.92×1011¹3.84×10¹¹m3, mainly concentrated inupper Sha4member of the Dongying, Zhanhua-Chezhen Depression by the accumulationcoefficient.