Enrichment and distribution of shale oil in the Cretaceous Qingshankou Formation,Songliao Basin,Northeast China |
| |
| Institution: | 1. State Key Laboratory of Petroleum Resource and Prospecting, China University of Petroleum, Beijing 102249, China;2. College of Geosciences, China University of Petroleum, Beijing 102249, China;3. Langfang Branch of Research Institute of Petroleum Exploration and Development, PetroChina, Langfang, Hebei Province 065007, China;1. State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development, Beijing 100083, China;2. College of Geosciences, China University of Petroleum, Qingdao 266580, China;3. Department of Earth and Environmental Sciences, The University of Texas at Arlington, Arlington, TX 76019, USA;4. Petroleum Exploration and Production Research Institute, SINOPEC, Beijing 100083, China;5. College of Geosciences, China University of Petroleum, Beijing 102249, China;6. School of Energy and Resources, China University of Geosciences, Beijing 100083, China;1. Key Laboratory of Shale Gas Exploration and Evaluation, Ministry of Land and Resources, China University of Geosciences, Beijing (CUGB), 100083, China;2. School of Energy and Resource, CUGB, 100083, China;3. Sinopec Petroleum Exploration and Production Research Institute, 100083, China;4. China University of Petroleum, Qingdao, Shandong Province, 266580, China;5. CNOOC Gas & Power Group, Beijing, 100083, China;1. PetroChina Research Institute of Petroleum Exploration & Development, Beijing 100083, China;2. National Energy Tight Oil & Gas R & D Center, Beijing 100083, China;3. CNPC Key Laboratory of Oil & Gas Reservoirs, Beijing 100083, China;1. College of Earth Sciences, Jilin University, 130061 Changchun, China;2. Key Laboratory of Oil Shale and Coexistent Energy Minerals of Jilin Province, 130061 Changchun, China;3. Key Laboratory for Evolution of Past Life and Environment in Northeast Asia (Jilin University), Ministry of Education, 130026 Changchun, China;4. China National Offshore Oil Corporation (Tianjin Branch), 300452 Tianjin, China;5. Daqing Oil Field Company, 163113 Daqing, China;1. Deep Oil and Gas Key Laboratory, China University of Petroleum (East China), Qingdao, Shandong 266580, China;2. No.7 Oil Recovery Plant of PetroChina Changqing Oilfield Company, Xi''an, Shaanxi 710000, China;3. Fengcheng Oil Recovery Plant of PetroChina Xinjiang Oilfield Company, Karamay, Xinjiang 834000, China;1. Key Laboratory of Tectonics and Petroleum Resources, China University of Geosciences (Wuhan), Ministry of Education, Wuhan 430074, China;2. SINOPEC Northeast Oil and Gas Branch Company, Changchun, Jilin 130062, China;3. Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, AB T6G 2E3, Canada |
| |
| Abstract: | The Songliao Basin is a large-scale petroliferous basin in China. With a gradual decline in conventional oil production, the exploration and development of replacement resources in the basin is becoming increasingly important. Previous studies have shown that the Cretaceous Qingshankou Formation (K2qn) has favorable geological conditions for the formation of shale oil. Thus, shale oil in the Qingshankou Formation represents a promising and practical replacement resource for conventional oil. In this study, geological field surveys, core observation, sample tests, and the analysis of well logs were applied to study the geochemical and reservoir characteristics of shales, identify shale oil beds, build shale oil enrichment models, and classify favorable exploration areas of shale oil from the Cretaceous Qingshankou Formation. The organic matter content is high in shales from the first member of the Cretaceous Qingshankou Formation (K2qn1), with average total organic carbon (TOC) content exceeding 2%. The organic matter is mainly derived from lower aquatic organisms in a reducing brackish to fresh water environment, resulting in mostly type I kerogen. The vitrinite reflectance (Ro) and the temperature at which the maximum is release of hydrocarbons from cracking of kerogen occurred during pyrolysis (Tmax) respectively range from 0.5% to 1.1% and from 430 °C to 450 °C, indicating that the K2qn1 shales are in the low-mature to mature stage (Ro ranges from 0.5% to 1.2%) and currently generating a large amount of oil. The favorable depth for oil generation and expulsion is 1800–2200 m and 1900–2500 m, respectively as determined by basin modeling. The reserving space of the K2qn1 shale oil includes micropores and mircofractures. The micropore reservoirs are developed in shales interbedded with siltstones exhibiting high gamma ray (GR), high resistivity (Rt), low density (DEN), and slightly abnormal spontaneous potential (SP) in the well-logging curves. The microfracture reservoirs are mainly thick shales with high Rt, high AC (acoustic transit time), high GR, low DEN, and abnormal SP. Based on the shale distribution, geochemical characteristics, reservoir types, fracture development, and the process of shale oil generation and enrichment, the southern Taikang and northern Da'an are classified as two favorable shale oil exploration areas in the Songliao Basin. |
| |
| Keywords: | Songliao Basin Cretaceous Source rocks Shale oil Favorable area |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
