Enrichment Characteristics And The Prediction Of Favorable Target Areas Of Shale Oil In Dongying Sag

Dongying sag is one of the oil-rich sag of the eastern continental basin in China,its main hydrocarbon source rocks locate in the upper section of the upper of 4 th member and the lower of 3 th member of the Shahejie formation.Dongying sag is also the main development zone of shale oil with a great potential for exploration.The current studys of shale oil in Dongying sag are mainly concentrated in reservoir space,enrichment factors,and organic geochemical study.The knowledge of enrichment and the predict of advantageous zrone of shale oil which are conducive to explorate and develop are not enough in its target area system and deep.In that situation,shale oil enrichment pattern in the upper of 4 th member and the lower of 3 th member of the Shahejie formation of Dongying sag,based on the organic geochemical parameters and the inorganic mineral content of typical shale oil wells in Dongying sag,is setted up by optimizing the main control factors of shale oil enrichment,evaluating the strength of shale oil free resources,dividing the shale lithoslithosfacies and screening favorable.The favorable target areas of shale oil are selected based on the enrichment characteristic,and it also provides guidance for exploration and development of shale oil in Dongying sag.There are a few perspectives:?1?This paper analyzes the shale oil enrichment factor and optimizes lithoslithosfacies,including organic,as the research area's main control factors of the shale oil enrichment.And it's come from the basic research about the organic,mineral lithosfacies,reservoir characteristics,pressure system,buried depth,storage conditions,crude oil physical properties.This paper gets the ideal that research area has four kinds of the favorable lithosfacies of the mud-shale rock including rich orgnic grain laminar of calcareous shale,rich organic laminar siliceous shale,rich organic bedded calcareous shale and rich organic bedded calcareous shale.The ideal come from the classification of lithosfacies by the four components-three components in the research area litholithosfacies,and the analysis of enrichment of shale oil of the free resources strength.?2?There are some studys about the mud-shale organic heterogeneity and the shale oil resources using the characteristic of triple-division,which is the relationship bettween free hydrocarbon quantity?S₁?,chloroform bitumen“A”and total organic carbon mass fraction?TOC?,and the hydrocarbon index?100S₁/TOC?profile and?logR logging.Research has shown that research area could be divided into enriched resources?degree??,low efficient resources?degree??and ineffective resources?degree??;and the shale oil free resources in Dongying sag are mainly located in Lijing depression.?3?The prediction of lithosfacies in Dongying sag has been finished based on the rock lithosfacies prediction established by BP neural network and the shale oil free resources strength.And considering rich organic laminar-bedded calcareous shale and rich organic laminar-bedded siliceous shale as main gathering area of the shale oil free resources,and the shale oil free resource strength is more advantage than favorable lithosfacies to gather the shale oil.?4?Lijin sub-sag is the favorable target for shale oil in Dongying sag,which controlled by favorable litholithosfacies.And the favorable shale oil area of the lower of 3 th member of the Shahejie formation locates in the near of L79 well,the upper section of the upper of 4 th member locates in the near of L760 well.