|
1
|
Xie W, Gan H, Chen C, Vandeginste V, Chen S, Wang M, Wang J, Yu Z. A model for superimposed coalbed methane, shale gas and tight sandstone reservoirs, Taiyuan Formation, Yushe-Wuxiang Block, eastern Qinshui Basin. Sci Rep 2022; 12:11455. [PMID: 35794230 PMCID: PMC9259666 DOI: 10.1038/s41598-022-15868-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Accepted: 06/30/2022] [Indexed: 11/09/2022] Open
Abstract
Superimposed accumulation mechanism and model of vertical source rock-reservoir system of coal-measure gas is crucial to evaluate the exploration potential, and also the basis of co-exploration and co-production of coal measure gas. This work investigates the formation mechanism of various types of reservoirs (coalbed methane, shale gas, tight sandstone) in the Taiyuan Formation (Yushe-Wuxiang Block, eastern Qinshui Basin). Source rocks (coal seams and coal-measure mudstones) in the study area are characterized by type III kerogen, organic rich and over-mature, and reach a gas generation peak during the Early to Late Cretaceous. Coalbed methane mainly adsorbs on the surface of micropores, shale gas mainly occurs in micropores, macropores and micro-factures in adsorbed and free states, and tight sandstone gas mainly occurs in macropores in a free state. The combinations of successions are identified, coalbed methane, shale gas, and tight sandstone gas horizons are divided into a mudstone-sandstone reservoir (combination I), a coal-mudstone-sandstone reservoir (combination II), and a coal-mudstone reservoir (combination III). This division occurs from top to bottom in the succession and is identified on the basis of lithology, total organic carbon content (TOC) of mudstones, gas logging, superimposition relationships, and the source rock-reservoir-caprock assemblage. The strata thickness, continuity, and gas logging results of combination III comprise the most favorable conditions for fairly good development potential, followed by combination I. The development potential of combination II is poor due to the small strata thickness and poor continuity. The identification of superimposed reservoirs can provide an engineering reference for the exploration of coal-measure gas.
Collapse
Affiliation(s)
- Weidong Xie
- School of Earth Resources, China University of Geosciences, Wuhan, 430074, China.,Key Laboratory of Coalbed Methane Resources and Accumulation Process, Ministry of Education, China University of Mining and Technology, Xuzhou, 221008, China
| | - Huajun Gan
- School of Earth Resources, China University of Geosciences, Wuhan, 430074, China.
| | - Chongyu Chen
- Jiangsu China Coal Geology Engineering Research Institute, Changzhou, 213000, China
| | - Veerle Vandeginste
- Department of Materials Engineering, Campus Bruges, KU Leuven, 8200, Bruges, Belgium
| | - Si Chen
- School of Earth Resources, China University of Geosciences, Wuhan, 430074, China
| | - Meng Wang
- Key Laboratory of Coalbed Methane Resources and Accumulation Process, Ministry of Education, China University of Mining and Technology, Xuzhou, 221008, China.
| | - Jiyao Wang
- Key Laboratory of Coalbed Methane Resources and Accumulation Process, Ministry of Education, China University of Mining and Technology, Xuzhou, 221008, China
| | - Zhenghong Yu
- School of Earth Resources, China University of Geosciences, Wuhan, 430074, China
| |
Collapse
|