Physical simutation experiment investigation on hydraulic fracture propagation in high-dip coal seam

Authors

JIANG Wei, Fracturing and Acidizing Technology Service Center, PetroChina Research Institute of Petroleum Exploration &Development, Langfang 065007, China
ZHANG Jun, No.156 Coalfield Geological Exploration Team, Xinjiang Bureau of Coalfield Geology, Ürümqi 830000, China
ZHONG Jie, No.156 Coalfield Geological Exploration Team, Xinjiang Bureau of Coalfield Geology, Ürümqi 830000, China
ZHAO Chen, No.156 Coalfield Geological Exploration Team, Xinjiang Bureau of Coalfield Geology, Ürümqi 830000, China
TANG Zhuyun, No.156 Coalfield Geological Exploration Team, Xinjiang Bureau of Coalfield Geology, Ürümqi 830000, China
LU Haibing, Fracturing and Acidizing Technology Service Center, PetroChina Research Institute of Petroleum Exploration & Development, Langfang 065007, China
YI Xinbin, Fracturing and Acidizing Technology Service Center, PetroChina Research Institute of Petroleum Exploration & Development, Langfang 065007, China
WANG Hai, CNPC Bohai Drilling Engineering Co. Ltd., Tianjin 300000, China

Abstract

In order to study the hydraulic fracture geometry in high-dip coal seam, a large-scale true triaxial fracturing simulation system was used to carry out physical simulation experiments, and the hydraulic fracture geometry of the maximum horizontal principal stress along the strike direction and along the dip direction-in 60° dip coal seam were investigated respectively. Experimental results of the maximum principal stress direction along the strike direction show that: hydraulic fracture initiation is easily; fracture height is limited in the whole time; fracture connectivity is good; fracture propagates mainly along bedding and natural fracture, vertical fracture is formed; the influence of high-dip on stimulation is relatively small; massive volume stimulation is needed. Experimental results of the maximum principal stress direction along the dip direction show that: hydraulic fracture initiation is hard; fracture height is limited in the early time and out of control in the later period; fracture connectivity is poor; fracture is not easy to form influenced by joint, and hydraulic fracture propagates difficultly; fracture diversion and multi-stage breakdown can be observed in the fracturing curve; small volume but multi-stage stimulation is needed. The experimental results have a good guiding effect on the stimulation model and scale determination of the high-dip coal seam in Xinjiang and other regions.

Keywords

coalbed methane, high-dip angle, stress direction, hydraulic fracture geometry, physical simulation, constraction scale, Xinjiang Fukang

DOI

10.3969/j.issn.1001-1986.2020.03.007

Recommended Citation

JIANG Wei, ZHANG Jun, ZHONG Jie, et al. (2020) "Physical simutation experiment investigation on hydraulic fracture propagation in high-dip coal seam," Coal Geology & Exploration: Vol. 48: Iss. 3, Article 8.
DOI: 10.3969/j.issn.1001-1986.2020.03.007
Available at: https://cge.researchcommons.org/journal/vol48/iss3/8

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