Wen X, Jin J K, Chen Y H, et al.Effects of fracturing fluid pumping rate on fracture initiation behavior in hydraulic fracturing of methane hydrate-bearing sediments[J].Journal of Henan Polytechnic University(Natural Science) ,2026,45(6):23-31.

doi:10.16186/j.cnki.1673-9787.2024030065

Received:2024/03/25

Revised:2024/08/15

Published:2026/10/09

Effects of fracturing fluid pumping rate on fracture initiation behavior in hydraulic fracturing of methane hydrate-bearing sediments

Wen Xin1,2, Jin Jikai1,2, Chen Yanhua1, Zhang Yibo1

1.College of Civil and Architectural Engineering， North China University of Science and Technology， Tangshan  063210， Hebei， China；2.Hebei Collaborative Innovation Center for Applied Technology of Geotechnical Engineering Disaster Prevention and Mitigation， Tangshan  063299， Hebei， China

Abstract: Objectives To address the fact that the effects of the fracturing fluid pumping rate on the fracture initiation behavior and fracture characteristics of methane hydrate-bearing sediments remain unclear， the fracture initiation behavior and fracture characteristics of these sediments under hydraulic fracturing were investigated.  Methods Methane hydrate-bearing sediment specimens were prepared independently， and a multifunctional experimental simulation apparatus for hydraulic fracturing under multi-field coupled conditions was developed. Hydraulic fracturing tests were conducted on the specimens at fracturing fluid pumping rates of 1， 1.5， 3， 5， 8 and 10 mL/s. The effects of fracturing fluid pumping rate on hydraulic fracturing of methane hydrate-bearing sediments were analyzed， and the fracture propagation mechanism was investigated.  Results The results show that the fracturing fluid pumping rate has a significant effect on the fracture initiation pressure of methane hydrate-bearing sediments. The fracture initiation pressure gradually increases with increasing fracturing fluid pumping rate.  However， there is a threshold pumping rate of 5 mL/s， above which fracture initiation is promoted. Hydraulic fractures in methane hydrate-bearing sediments mainly initiate along bedding planes， and the fracture morphology varies considerably at different fracturing fluid pumping rates. The complex fractures formed during hydraulic fracturing are mainly Y-shaped and consist primarily of vertical and horizontal tensile fractures.  The fracturing fluid pumping rate is strongly correlated with fracture initiation time and injection volume.  Conclusions The study reveals the fracture evolution characteristics of hydraulic fracturing in methane hydrate-bearing sediment reservoirs and provides a reference for the application of hydraulic fracturing technology to natural gas hydrate development.

Key words: methane hydrate-bearing sediments; hydraulic fracturing; fracture initiation behavior; fracture characteristics