Hydrocarbon generation mechanism via the organic- inorganic interaction pathway and its geological pattern in ultra- deep sedimentary basins
Author:
Affiliation:

Clc Number:

Fund Project:

  • Article
  • |
  • Figures
  • |
  • Metrics
  • |
  • Reference
  • |
  • Related
  • |
  • Cited by
  • |
  • Materials
  • |
  • Comments
    Abstract:

    The continuous discovery of ultra- deep oil and gas around the world challenges the classical theory of hydrocarbon generation. The hydrocarbon generation process with exogenous hydrogen from organic- inorganic interactions has attracted wide attention. Based on the statistical data of geological observations, molecular hydrogen is widely distributed in sedimentary basins and its formation mechanism is complex. In geological environments, inorganic hydrogen derived from water, water- rock reactions and deep fluids is the main external source. Controlled hydrogenation simulation experiments reveal that the level of hydrogen fugacity in sedimentary basins is one of the essential factors regulating hydrocarbon generation, and the hydrocracking of kerogen is a preferential pathway for the hydrocarbon generation process in sedimentary basins. The premise of exogenous hydrogen participating in hydrocarbon generation is that the environmental hydrogen fugacity is greater than that of sedimentary organic matter. The range of this effect is constrained by the chemical composition and the structure of kerogen, and it probably starts after the peak of oil generation and ends approximately when the H/C of sedimentary organic matter is less than 0. 3. This demonstrates that hydrocarbon generation via organic- inorganic interactions is an effective pathway for hydrocarbon generation in ultra- deep strata of sedimentary basins. Within the effective range, the types of oil and gas resources are still determined by factors such as the types of kerogen (chemical composition and structure), maturity and heating history, with obvious stages and hydrocarbon generation modes different from the classical theory. With the participation of exogenous hydrogen, the oil generation yield can be slightly promoted in the mature stage and be significantly enhanced in the high- over maturity stage. Moreover, in the high- maturity stage, the hydrodealkylation reaction can increase the yield of light/condensate oil up to 50%, and in the over- maturity stage, the demethylation- ring opening reaction can increase the methane yield by approximately 5- fold. The new hydrocarbon generation model via the organic- inorganic interaction pathway expands the connotation of traditional hydrocarbon generation theory, establishes the theoretical foundation for ultra- deep oil and gas generation, and expands the vision of oil and gas exploration.

    Reference
    Related
    Cited by
Get Citation

Wu Jia, He Kun, Meng Qingqiang, Lu Hong, Zhong Ningning, Fang Peng, Wang Yuan, Ji Fujia, Yang Ya’nan, Huang Xiaowei, Li Kang, Zhao Zhongfeng.2023. Hydrocarbon generation mechanism via the organic- inorganic interaction pathway and its geological pattern in ultra- deep sedimentary basins[J]. Acta Geologica Sinica,97(3):961-972

Copy
Share
Article Metrics
  • Abstract:
  • PDF:
  • HTML:
  • Cited by:
History
  • Received:May 22,2022
  • Revised:July 05,2022
  • Adopted:July 07,2022
  • Online: March 30,2023
  • Published: