Characteristics and distribution of main source rocks in Xihu sag, East China Sea Basin

被引：0
|
作者：
Song C. [1 ]
Cao Q. [2 ,3 ]
Ye J. [2 ,3 ]
Lei C. [4 ]
Shan C. [2 ,3 ]
机构：
[1] School of Earth Sciences and Resources, China University of Geosciences, Beijing
[2] College of Resources, China University of Geosciences, Wuhan, 430074, Hubei
[3] Key Laboratory of Tectonics and Petroleum Resources, Ministry of Education, China University of Geosciences, Hubei, 430074, Wuhan
[4] PetroChina Jidong Oilfield Company, Tangshan, 063000, Hebei
来源：
Shiyou Xuebao/Acta Petrolei Sinica | 2016年 / 37卷 / 08期
关键词：
Gas-source correlation; Huagang Formation; Maturity; Pinghu Formation; Source rock; Xihu depression;
D O I：
10.7623/syxb201608003
中图分类号：
学科分类号：
摘要：
Based on a large number of exploration achievements in recent years, in combination with geochemical analysis and basin simulation technology, this study comprehensively analyzes and determines the organic geochemistry and distribution characteristics of source rocks in Xihu depression, and also discusses the genesis and source of regional natural gas as well. The results show that two major sets of source rocks in Pinghu Formation and Huagang Formation are developed in Xihu depression, mainly composed of dark mudstone and coal. The coal-measure source rocks in Pinghu Formation are the major hydrocarbon supply layers in the study area, of which the maximum thickness was observed in the middle of Baoshu slope belt and the mid-south part of Santan Deep depression-Central Anticline Belt, gradually thinning along both sides of the depression. The evaluations of source rocks show that Pinghu Formation is dominated by moderate/high-quality source rocks, where the Type II2 and Type III mudstones and Type III coal organic matter are mainly development. Presently, Pinghu Formation in the Santan Deep depression and Central Anticline Belt is during the mature-over mature stage, of which the source rocks are early mature with gas generation intensity obviously higher than oil generation intensity. The main sources of organic matter include terrigenous higher plants, which were formed in the fresh-brackish water oxidized sedimentary environment. Natural gas in Xihu depression is dominated by hydrocarbon gas, mostly belonging to coal-type gas, of which the maturity (Ro) is ranged between 0.58%-1.97%, indicating the thermal evolution product of mature and highly mature source rocks. Natural gas generated in Huagang Formation of Central Anticline Belt and Santan Deep depression was mainly originated from the mature and highly mature source rocks of Lower Pinghu Formation, to which the mature source rocks of Lower Huagang Formation also made contributions. In the middle of Baochu slope belt, natural gas was self-produced in Huagang Formation, Pinghu Structural Zone. Meanwhile, the natural gas was mostly self-produced in Pinghu Formation, while the highly mature gas samples from some gas wells might be originated from the highly mature source rocks in Pinghu Formation of the adjacent Santan Deep depression. A systematic analysis on the characteristics and distribution laws of chief source rocks in Xihu depression is of practical guiding significance to further oil and gas exploration. © 2016, Editorial Office of ACTA PETROLEI SINICA. All right reserved.
引用
收藏
页码：962 / 974
页数：12
相关论文
共 39 条
  • [31] Peters K.E., Moldowan J.M., Effects of source, thermal maturity, and biodegradation on the distribution and isomerization of homohopanes in petroleum, Organic Geochemistry, 17, 1, pp. 47-61, (1991)
  • [32] Jia J., Xu X., Sun B., Oil/gas geochcmical character in the Xihu trough of the East China Sea, Offshore Oil, 20, 2, pp. 1-7, (2000)
  • [33] Fu N., Li Y., Chen G., Et al., Pooling mechanisms of “evaporating fractionation” of oil and gas in the Xihu depression, East China Sea, Petroleum Exploration and Development, 30, 2, pp. 39-42, (2003)
  • [34] Su A., Chen H., Geochemical characteristics of oil and source rock, origin and genesis of oil in Xihu depression, East China Sea Basin, Earth Science: Journal of China University of Geosciences, 40, 6, pp. 1073-1082, (2015)
  • [35] Huang R., Formation and Distribution Law of Low Mature Oil and Gas Condensate Reservoir in China, (1997)
  • [36] Su A., Chen H., Wang C., Et al., Source of natural gas in Xihu depression of the East China Sea Basin, Geological Science and Technology Information, 33, 1, pp. 157-162, (2014)
  • [37] Prinzhofer A., Mello M.R., Takaki T., Geochemical characterization of natural gas: a physical multivariable approach and its applications in maturity and migration estimates, AAPG Bulletin, 84, 8, pp. 1152-1172, (2000)
  • [38] Liu W., Xu Y., A two-stage model of carbon isotopic fractionation in coal-gas, Geochimica, 28, 4, pp. 359-366, (1999)
  • [39] Su A., Chen H., Ma Y., Et al., Geological conditions and main controlling factors of gas washing in Kongqueting region in Xihu depression, Eastern Sea Basin, Natural Gas Geoscience, 26, 2, pp. 292-300, (2015)
1234