The Space Relation Between Hydrocarbon Source Rock And Reservoir And Their Evolution

The dissertation researches firstly the relation between main hydrocarbon source rock and main reservoir and their evolution, then research the relation of them of Dongying sag and the relation between turbidite fan and underlying hydrocarbon source rock of Lijialou oil field. Then, there is an analysis how space relation influences reservoir formation.There are two types to the space relationship between hydrocarbon source rock and reservoir of big and medium oil field inside and outside of China. One is separation, another is contact. 33 are separation type in 39 oil and gas field of China. It occupies 84.6%. 213 are separation type in the 241 oil and gas field of world. It occupies 88.6%.The main hydrocarbon source rock of Dongying sag lies in the S3 and S4. The reservoir of Dongying sag include basement, S4, S3, S2, S4, S1, Dongying formation and Guantao formation. Its reserves is 16.0548 bt. The reserves of S2-Guantao formation is 10.6651bt and occupies 66.43%. It is obvious that main hydrocarbon source rock separate with main reservoir.The main reservoir of Liangjialou oil field of Dongying sag is turbidite fan of upper formation of S3. It contacts directly with shale of middle and lower formation of S3. Under the sandstone, the rock contacting with sandstone is the gray silty shale which content of organic carbon is 0.38-0.59%. The thickness of gray silty shale is 4.85m. It is the black bathile shale whose content of organic carbon is 1.60-6.31% under the gray silty sandstone. The silty sandstone is not main hydrocarbon source rock.The deposit influences the space relationship between hydrocarbon source rock and reservoir. Hydrocarbon source rock formed in the calm and strong reductive environment, for example half-deep lake-deep facies, estuarine facies, shallow-sea fades and paludal facies etc. Reservoir formed in the turbulent and oxidized environment, for example alluvial fan facies, fluvial facies, delta facies, aeolian facies aad shallow-sea facies etc. The difference of sedimentary environment results the separated space relationship between hydrocarbon source rock and reservoir. Only iadividual condition it results the contact for example the environment of deep density current.Diagenesis has few influence to space relationship between hydrocarbon source rock and reservoir caused by sediment. The influence of diagenesis mainly limits inside of reservoir and hydrocarbon source rock and mainly show the change of porosity and diagenesis feature.Tissot( 1978,1984) thought that oil and gas formed reservoir after firstly and secondly migrate in the geological framework of frequent deposition and contacting each other of hydrocarbon source rock and reservoir. But the process is limit because the separation is majority and the contact is minority through anglicizing spacerelationship between hydrocarbon source rock and reservoir.