Configuration types of fault-sand and its control on hydrocarbon accumulation in the East Slope of Chengdao, Bohai Bay Basin
ZHANG Zaizhen, ZENG Jianhui, LIAO Wenhao, ZHANG Benhua, WANG Zhiwei, WU Qunhu, CUI Huwang, QIAO Juncheng
1 College of Geosciences, China University of Petroleum-Beijing, Beijing 102249, China 2 Offshore Oil Production Plant, SINOPEC Shengli Oilfield Company, Dongying 257237, China 3 Shengli Oilfield Company, SINOPEC, Dongying 257000, China
Faults and sand bodies are the main transport elements of hydrocarbon migration of the Dongying Formation in the East Slope of Chengdao. In order to explore the mechanism of hydrocarbon migration and accumulation under the control of fault-sand configuration transportation conditions, the types of fault-sand configuration of the Dongying Formation in the East Slope of Chengdao are first divided based on the precise interpretation of seismic data and RMS attribute analysis of sand body. The fault-sand configuration transport properties are quantitatively evaluated by using the relative transport index of the sandstone transport layer RTi and fault lateral conductivity index FLSI indices. The control effect of different types of fault-sand configuration on hydrocarbon migration and accumulation was then analyzed with the HMIE index and Trinity hydrocarbon migration numerical simulation. The results show that the fault-sand configuration in the East Slope of Chengdao can be divided into three types, forward configuration of fault-sand, reverse configuration of fault-sand and compounds of primary faults and secondary faults configuration of fault-sand according to the spatial superposition relationship between faults and sand bodies. The controlling effect of fault-sand configuration on hydrocarbon accumulation is mainly reflected in the following aspects: (1) Control the area of hydrocarbon migration and accumulation; the hydrocarbon migration and accumulation was controlled by transportation conductivity of fault-sand configuration when RTi > 0.15, RTi are positively associated with the degree of hydrocarbon accumulation on the slope region, hydrocarbons are easily sealed laterally to form reservoirs on the fault terrace zone when FLSI≥0.45. (2) Control the dominant migration path of hydrocarbon; the types, the communicating effectiveness with the source rock and transport capacity of fault-sand configuration determine the dominant migration paths of hydrocarbon. The HMIE index and Trinity simulation analysis show that there are three dominant migration paths, namely, the depression area towards the fault belt of southern Shenghai 10, the depression area towards the fault belt of southern Shenghai 8, and the depression area belt towards the fault terrace area. (3) Control the distribution and accumulation of hydrocarbon; The forward configuration of fault-sand mainly plays the role of stepping hydrocarbon transport, the reverse configuration of fault-sand type can block hydrocarbon accumulation laterally, and the compounds of primary faults and secondary faults configuration of fault-sand plays the role of diverting hydrocarbon first and then enriching it. Different types of fault-sand configuration control the hydrocarbon accumulation pattern, which has the characteristics of “zonal control, vertical differentiation and multi-layer system enrichment”.
Key words：
fault-sand configuration, transport capacity, hydrocarbon accumulation, hydrocarbon accumulation mode, East Slope of Chengdao
張?jiān)谡? 曾濺輝, 廖文毫, 張本華, 王志偉, 武群虎, 崔虎旺, 喬俊程. 渤海灣盆地埕島東斜坡斷—砂組合樣式及其對(duì)油氣富集的控 制作用. 石油科學(xué)通報(bào), 2023, 06: 707-723 ZHANG Zaizhen, ZENG Jianhui, LIAO Wenhao, ZHANG Benhua, WANG Zhiwei, WU Qunhu, CUI Huwang, QIAO Juncheng. Configuration types of fault-sand and its control on hydrocarbon accumulation in the East Slope of Chengdao, Bohai Bay Basin. Petroleum Science Bulletin, 2023, 05: 707-723.
