Favorable Lithofacies Classification And Evaluation Of Shale Oil And Gas In Dongying Depression

We take the Dongying depression as the study area to study in this article. mainlyanalysised facies types of shale oil and gas and reaserched all types.At last concluded themost favorable facies type. It has an important significance for shale oil and gasexploration targets of Dongying Depression.There are mainly developed two set of shales in the lower member of Es3and theupper member of Es4in Dongying Depression of Paleogene.And they are the mainhydrocarbon layer of Dongying Depression.This article choose the Es3₂,3and Es4₂,3asthe main layer segment review by the oil and gas and small layer contrast.We through the analysis of core observation, thin section identification and X-diffraction of rocks and minerals, according to the rock structural characteristics （lamellar,layer, block）, minerals （calcite and clay mineral content） features to classify the Dongyingsag of shale:oil shale, laminar gray laminated shale, laminar gray matter in oil shale;layered class lithofacies consists of layered shale and the lamellar gray shale facies; blocktype facies including massive shale facies and massive gray mud facies.This paper studies the influence factors of shale oil and gas in Dongying depression.We found that lamellar type facies most enrichment for shale oil and gas; brittle mineralhigh area for shale oil and gas output; tectonic movement and the development of the crackwill affect the accumulation of shale oil and gas, oil and gas near fracture more enrichment;area of abnormal pressure is also good for shale oil and gas output.Integrated various factors affecting the shale oil and gas enrichment, concluded thatthe Es3₃and Es4₂layer are the most favourable horizons for shale oil and gas. The twosets of hydrocarbon source rock distribution area, effective thickness, high organic carboncontent, organic matter reached a mature stage, brittle mineral content, development oflamellar type facies, pore and fracture development. Closer to the center of depression areaof shale more conducive to the development of shale oil and gas.