Formation mechanisms of nano-scale pores/fissures and shale oil enrichment characteristics for Gulong shale，Songliao Basin

被引：0
|
作者：
Longde S. [1 ,2 ,3 ]
Xiaojun W. [1 ,2 ,4 ]
Zihui F. [1 ,2 ,5 ]
Hongmei S. [1 ,2 ,5 ]
Huasen Z. [1 ,2 ,5 ]
Bo G. [1 ,2 ,5 ]
Hang J. [1 ,2 ,6 ]
机构：
[1] National Key Laboratory of Continental Shale Oil, Heilongjiang, Daqing
[2] Heilongjiang Provincial Key Laboratory of Continental Shale Oil, Heilongjiang, Daqing
[3] PetroChina Company Limited, Beijing
[4] Daqing Oilfield Company Ltd., PetroChina, Heilongjiang, Daqing
[5] Exploration and Development Research Institute, Daqing Oilfield Company Ltd., PetroChina, Heilongjiang, Daqing
[6] Research Institute of Petroleum Exploration & Development, PetroChina, Beijing
来源：
Oil and Gas Geology | 2023年 / 44卷 / 06期
关键词：
enrichment model; Gulong shale; organo-clay complex; Qingshankou Formation; shale oil; Songliao Basin; organic-inorganic pore-fissure system;
D O I：
10.11743/ogg20230602
中图分类号：
学科分类号：
摘要：
：The Cretaceous Gulong shale oil reservoirs in the Songliao Basin are composed of organic -rich continental shales with high clay content，interbedded with minor amounts of thinly laminated calcareous sandstones and dolomites. Currently，there is a lack of studies on the pore-fissure system and shale oil enrichment pattern of these reservoirs. Based on the data from experiments and analyses including argon ion milling-field emission scanning electron microscopy（FE-SEM），energy-dispersive X-ray spectroscopy（EDS），high-pressure mercury injection analysis， low-temperature nitrogen adsorption experiment， fluorescence thin section observation，X-ray diffraction（XRD）mineralogy of whole rock，and geochemical analysis，we investigate the organic-inorganic pore-fissure system in the Gulong shale and its relationship with shale oil enrichment. The results are as follows：（1）The Gulong shale hosts a dual-porosity reservoir system consisting of matrix pores and microfissures. Matrix pores serve as shale oil enrichment spaces，while microfissures provide both storage spaces and seepage pathways for shale oil；（2）Influenced by multiple factors such as mineral evolution，hydrocarbon generation，and cracking and conversion of crude oil，the Gulong shale exhibits varying pore-fissure combinations at different evolutionary stages. At the mature stage，the shale predominantly contains micron-scale dissolved pores and organo-clay complex pores/fissures（i. e. ，pores/fissures with clay minerals as framework and formed as a result of hydrocarbon generation）. In contrast，the highly mature stage is characterized by nano-scale organo-clay-complex pores/fissures and bedding fissures；（3）There exists a coupling relationship between the shale oil enrichment and the evolution of pore-fissure combinations for the Gulong shale. The shale oil primarily accumulates within inorganic intergranular and intercrystalline pores at the low mature stage，while it is relatively heavy and predominantly concentrates in dissolved pores and organo-clay complex pores/fissures at the mature stage. At the highly mature stage，the shale oil becomes lighter and largely gets enriched in organo-clay complex pores/fissures and bedding fissures. © 2023 Editorial Department of Oil and Gas Geology. All rights reserved.
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页码：1350 / 1365
页数：15
相关论文
共 46 条
  • [21] WANG Yuman, DONG Dazhong, YANG Hua, Et al., Quantitative characterization of reservoir space in the Lower Silurian Longmaxi Shale， southern Sichuan， China ［J］, Science China Earth Sciences, 44, 6, pp. 1348-1356, (2014)
  • [22] Feiyu WANG, Jing GUAN, Weiping FENG, Et al., Evolution of overmature marine shale porosity and implication to the free gas volume［J］, Petroleum Exploration and Development, 40, 6, pp. 819-824, (2013)
  • [23] Lin WEI, MASTALERZ M，, SCHIMMELMANN A，, Et al., Influence of soxhlet-extractable bitumen and oil on porosity in thermally maturing organic-rich shales［J］, International Journal of Coal Geology, 132, pp. 38-50, (2014)
  • [24] JIANG Zhenxue, LI Xin, WANG Xingmeng, Et al., Characteristic differences and controlling factors of pores in typical South China shale［J］, Oil & Gas Geology, 42, 1, pp. 41-53, (2021)
  • [25] Fenglan WANG, Zihui FENG, Xue WANG, Et al., Effect of organic matter， thermal maturity and clay minerals on pore formation and evolution in the Gulong Shale，Songliao Basin，China［J］, Geoenergy Science and Engineering, 223, (2023)
  • [26] HE Wenyuan, CUI Baowen, WANG Fenglan, Et al., Study on reservoir spaces and oil states of the Cretaceous Qingshankou Formation in Gulong Sag，Songliao Basin［J］, Geological Review, 68, 2, pp. 693-741, (2022)
  • [27] LI Wenbiao, LU Shuangfang, LI Junqian, Et al., Carbon isotope fractionation during shale gas transport： Mechanism，characterization and significance ［J］, Science China Earth Sciences, 50, 4, pp. 553-569, (2020)
  • [28] HUO Qiuli, ZENG Huasen, ZHANG Xiaochang, Et al., Organic matter characteristics and shale oil formation of Gulong shale in Songliao Basin［J］, Petroleum Geology & Oilfield Development in Daqing, 39, 3, pp. 86-96, (2020)
  • [29] SCHMIDT V, MCDONALD D A., The role of secondary porosity in the course of sandstone diagenesis, Aspects of Diagenesis, pp. 175-207, (1979)
  • [30] BARUCH E T, KENNEDY M J, Et al., Feldspar dissolution-enhanced porosity in Paleoproterozoic shale reservoir facies from the Barney Creek Formation （McArthur Basin，Australia）［J］, AAPG Bulletin, 99, 9, pp. 1745-1770, (2015)
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