Xie G.,Coal Geological Bureau of Jiangxi Province 223 Geological Bureau |
Xie G.,China University of Mining and Technology |
Liu S.,Coal Geological Bureau of Jiangxi Province 223 Geological Bureau |
Shen Y.,China University of Mining and Technology |
And 3 more authors.
Zhongguo Kuangye Daxue Xuebao/Journal of China University of Mining and Technology | Year: 2015
Based on measured sections, geological survey on outcrops and test results analysis of samples, the reservoir-forming geological conditions of the Hetang Formation shale gas reservoir in northeastern Jiangxi area was discussed in the following aspects: shale distribution and sedimentary characteristics, geochemical characteristics, reservoir characteristics and preservation conditions of shale gas; and this shale reservoir was considered to have a good physical properties. The results show that the reservoir thickness of Hetang Formation shale ranges from 25 m to 200 m; the shale is widely distributed and developed in deep-water shelf sedimentary environment. The organic matter type of shale is type I; the total organic carbon content is high and in the range of 0.54%-11.40% with the average of 5.75%; the thermal evolution degree is also high with Ro ranging from 2.35% to 4.90% with the average of 3.22%, being in the postmaturity stage. The shale has abundant brittle minerals consisting of the primary quartz and a small quantity of feldspar and carbonate minerals. The clay minerals content is moderate with the primary illite and secondary illite-montmorillonite mixed-layer mineral. The types of micropore of shale include inter-crystalline pores, organic pores, secondary dissolution pores and microcracks. The shale reservoirs have an average porosity of 2.2% and average permeability of 0.006 mD. Moreover, based on the favorable area optimization standard of China's marine shale gas, the Lower Cambrian Hetang Formation shale in northeastern Jiangxi Province has ideal shale gas exploration and development conditions and the favorable areas are located in the Mopanshan and Shangrao areas. ©, 2015, China University of Mining and Technology. All right reserved.