Reservoir Characteristics and Hydrocarbon Accumulation Regularity of the Chang 6 Oil bearing Beds in the Chuankou Oil Field, Shaanxi Province
川口油田长6段油层组储集层特征与油气富集规律

Based on analysing sedimentary characteristics of the Chang 6 oil bearingbeds in the Chuankou oil field, the author has studied petrological characteristics,diagenesis and porosity structure and suggest that the evolution of the environment during deposition the Chang 6 oil bearing beds represents the history when the water platform delta was gradually transformed into a terrestrial plain. The meander channel sandbodies are the major oil bearing facies in this area. The cementation of laumontite, calcite and chlorite, the pressure solution, as well as the dissolution of laumontite and feldspar are the main causes to effect reservoir ability of oil bearing arkoses. The evolution of porosity has a close relationship with the diagenetic history and the evolution of basin. The Chang 6 oil bearingbeds and its up down position constitute a good resoure reservoir cap rock combination. The Chang 6 1 and the Chang 6 2 members are the major reservoirs in the Chuankou area.