Petroleum Reservoir Evaluation and Development ›› 2021, Vol. 11 ›› Issue (4): 506-513.doi: 10.13809/j.cnki.cn32-1825/te.2021.04.005

• Exploration & Development of Shale Oil and Gas • Previous Articles     Next Articles

Evaluation of shale oil migration and accumulation rules based on geochemical parameters of source rocks

DAI Bo1(),LI Erdang1,WANG Xiaojun1,CAO Li1,MA Xiong1,ZANG Qibiao2,3()   

  1. 1. No. 1 Oil Production Plant, PetroChina Changqing Oilfield Company, Yan’an, Shaanxi 716000, China
    2. State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, China
    3. College of Geosciences, China University of Petroleum, Beijing 102249, China
  • Received:2020-09-18 Online:2021-08-19 Published:2021-08-26
  • Contact: ZANG Qibiao E-mail:cqytdb@126.com;1448906535@qq.com

Abstract:

Taking the source rock of Chang 7 Member in Ansai area of Ordos Basin as the research object, the differentiation characteristics of shale oil in the process of migration and accumulation are discussed in depth through a series of testing methods, such as TOC test, rock pyrolysis and chromatography-mass spectrometry. The results show that the hydrocarbon generation potential of different source rocks in the study area is quite different. The shale has the strongest hydrocarbon generation capacity, while that of the interaction layer of sandstone and mudstone is the weakest. The high content of free hydrocarbon in interaction layer of sandstone and mudstone results from the receipt of external free hydrocarbon. The distribution of geochemical parameters of shale oil in different lithology is different. Among them, the sand mud interaction layer is rich in saturated hydrocarbon but relatively poor in nonhydrocarbon and asphaltene, while the shale and the mudstone are rich in nonhydrocarbon and asphaltene but relatively poor in saturated hydrocarbon. The properties of crude oil, thickness of source reservoir and physical properties have effects on shale oil migration and accumulation. Shale oil in thin-layer source rocks and small molecular hydrocarbon components are easy to migrate. Shale oil in thick-layer source rocks and macromolecular hydrocarbon components tend to remain in the source rocks.

Key words: shale oil, saturated hydrocarbon, migration and accumulation characteristics, main control factor, Ansai area

CLC Number: 

  • TE122.2