Geological characteristics of shale rock system and shale oil exploration breakthrough in a lacustrine basin: A case study from the Paleogene 1st sub-member of Kong 2 Member in Cangdong sag, Bohai Bay Basin, China

被引：0

作者：

Zhao X. ^{[1
]}

Zhou L. ^{[1
]}

Pu X. ^{[1
]}

Jin F. ^{[1
]}

Han W. ^{[1
]}

Xiao D. ^{[1
]}

Chen S. ^{[2
]}

Shi Z. ^{[1
]}

Zhang W. ^{[1
]}

Yang F. ^{[1
]}

机构：

[1] PetroChina Dagang Oilfield Company, Tianjin

[2] China University of Petroleum (East China), Qingdao

来源：

| 2018年 / Science Press卷 / 45期

关键词：

Bohai Bay Basin; Cangdong sag; Fine grained deposits; Horizontal well; Paleogene Kongdian Formation; Shale oil; Shale reservoir sweet spot; Volume fracturing;

D O I：

10.11698/PED.2018.03.01

中图分类号：

学科分类号：

摘要：

A deep understanding of the basic geologic characteristics of the fine-grained shale layers in the Paleogene 1st sub-member of Kong 2 Member (Ek2 1) in Cangdong sag, Bohai Bay Basin, is achieved through observation of 140 m continuous cores and systematic analysis of over 1 000 core samples from two wells. Basic geological conditions for shale oil accumulation are proposed based on the unconventional geological theory of oil and gas. The shale rock system mainly developed interbedded formation of felsic shale, limy and dolomite shale and carbonates; high quality hydrocarbon source rock formed in the stable and closed environment is the material base for shale oil enrichment; intergranular pores in analcite, intercrystalline pores in dolomite and interlayer micro-fractures make tight carbonate, limy and dolomite shale and felsic shale effective reservoirs, with brittle mineral content of more than 70%; high abundance laminated shale rock in the lower section of Ek2 1 is rich in shale oil, with a total thickness of 70 m, burial depth between 2 800 to 4 200 m, an average oil saturation of 50%, a sweet spot area of 260 km2 and predicted resources of over 5×108 t. Therefore, this area is a key replacement domain for oil exploration in the Kongdian Formation of the Cangdong sag. At present, the KN9 vertical well has a daily oil production of 29.6 t after fracturing with a 2 mm choke. A breakthrough of continental shale oil exploration in a lacustrine basin is expected to be achieved by volume fracturing in horizontal wells. © 2018, The Editorial Board of Petroleum Exploration and Development. All right reserved.

引用

页码：361 / 372

页数：11

共 28 条

[1] Jia C., Breakthrough and significance of unconventional oil and gas to classical petroleum geological theory, Petroleum Exploration and Development, 44, 1, pp. 1-11, (2017)
[2] Zou C., Zhai G., Zhang G., Et al., Formation, distribution, potential and prediction of global conventional and unconventional hydrocarbon resources, Petroleum Exploration and Development, 42, 1, pp. 13-26, (2015)
[3] Song Y., Li Z., Jiang Z., Et al., Progress and development trend of unconventional oil and gas geological research, Petroleum Exploration and Development, 44, 4, pp. 638-648, (2017)
[4] Zhou Q., Yang G., Definition and application of tight oil and shale oil terms, Oil and Gas Geology, 33, 4, pp. 541-544, (2012)
[5] EIA, Technically recoverable shale oil and shale gas resources: An assessment of 137 shale formations in 41 countries outside the United States, (2013)
[6] U.S. Energy Information Administration. Annual energy outlook 2017, (2017)
[7] Wang H., Ma F., Tong X., Et al., Assessment of global unconventional oil and gas resources, Petroleum Exploration and Development, 43, 6, pp. 850-862, (2016)
[8] Zhang T., Peng Z., Yang W., Et al., Enlightenments of American shale oil research towards China, Lithologic Reservoirs, 27, 3, pp. 1-10, (2015)
[9] Li D., Liu Z., Zhang G., Et al., Comparison and revelation of tight oil accumulation conditions, distribution characteristics and development status between China and U.S., Natural Gas Geoscience, 28, 7, pp. 1126-1138, (2017)
[10] Pollastro R.M., Total petroleum system assessment of undiscovered resources in the giant Barnett Shale continuous (unconventional) gas accumulation, Fort Worth Basin, Texas, AAPG Bulletin, 91, 4, pp. 551-578, (2007)

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