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Volume 37 Issue 3
Jun 2026
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Wenjibin Sun, Zhonghu Wu, Yujun Zuo, Chao Pan, Hao Liu, Baofeng Lan, Jianyun Lin, Bin Chen, Qinggang Chen. Enrichment Characteristics of Normal-Pressure Marine Shale Gas in the Complex Tectonic Zone: A Case Study of the Lower Cambrian Niutitang Formation in Northern Guizhou. Journal of Earth Science, 2026, 37(3): 1253-1268. doi: 10.1007/s12583-024-0006-3
Citation: Wenjibin Sun, Zhonghu Wu, Yujun Zuo, Chao Pan, Hao Liu, Baofeng Lan, Jianyun Lin, Bin Chen, Qinggang Chen. Enrichment Characteristics of Normal-Pressure Marine Shale Gas in the Complex Tectonic Zone: A Case Study of the Lower Cambrian Niutitang Formation in Northern Guizhou. Journal of Earth Science, 2026, 37(3): 1253-1268. doi: 10.1007/s12583-024-0006-3

Enrichment Characteristics of Normal-Pressure Marine Shale Gas in the Complex Tectonic Zone: A Case Study of the Lower Cambrian Niutitang Formation in Northern Guizhou

doi: 10.1007/s12583-024-0006-3
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  • Corresponding author: Zhonghu Wu, wuzhonghugzu@163.com
  • Received Date: 19 Jan 2024
  • Accepted Date: 28 Mar 2024
  • Available Online: 10 Jun 2026
  • Issue Publish Date: 30 Jun 2026
  • The Lower Cambrian Niutitang Formation is a crucial stratum for the exploration of normal-pressure marine shale gas in southern China, with great development potential. To research the normal-pressure shale gas accumulation of the Niutitang Formation in the complex tectonic zone, the shale cores in northern Guizhou were subjected to X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) observation, and tests were conducted to determine total organic content (TOC), bitumen reflectance, and nitrogen isotopes. The results indicate that the equivalent vitrinite reflectance of cores varies from 2.30% to 3.73%, and the TOC content of cores varies from 3.8% to 7.8%. The total gas content of three wells in northern Guizhou is 0.5, 0.3, and 1.4 m3/t, respectively. The TOC content of the shale in the syncline structure is higher than that of the shale in the anticline structure. Nitrogen in shale gas originates primarily from the thermal ammoniation of organic matter, the atmosphere, and the deep crust. Shale gas preservation is favorable in regions with a large range of lifting, and small lifting differences. The syncline is broad and gentle with few faults have better gas accumulation conditions. The Niutitang Formation in the residual syncline of the study area has better gas content than that of other structures. Exploration of shale gas accumulation sweet spots in northern Guizhou should focus on the broad-gentle synclines with minimal changes in stratigraphic lifting, few faults, and no hydrothermal activity at the edges of paleo-uplifts.

     

  • Electronic Supplementary Materials: Supplementary materials (Figures S1–S7) are available in the online version of this article at https://doi.org/10.1007/s12583-024-0006-3.
    Conflict of Interest
    The authors declare that they have no conflict of interest.
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