文献类型：期刊文献

英文题名：Frictional stability and permeability evolution of fractures subjected to repeated cycles of heating-and-quenching: granites from the Gonghe Basin, northwest China

作者：Cui, Li[1,2];Zhang, Fengshou[1,2];An, Mengke[1,2];Zhuang, Li[3];Elsworth, Derek[4,5,6];Zhong, Zhen[7]

机构：[1]Tongji Univ, Coll Civil Engn, Dept Geotech Engn, Shanghai 200092, Peoples R China;[2]Tongji Univ, Key Lab Geotech & Underground Engn, Minist Educ, Shanghai 200092, Peoples R China;[3]Korea Inst Civil Engn & Bldg Technol, Goyang 10223, Gyeonggi, South Korea;[4]Penn State Univ, EMS Energy Inst, Dept Energy & Mineral Engn, University Pk, PA 16802 USA;[5]Penn State Univ, Ctr G3, University Pk, PA 16802 USA;[6]Penn State Univ, Dept Geosci, University Pk, PA 16802 USA;[7]Shaoxing Univ, Sch Civil Engn, Shaoxing 312000, Peoples R China

年份：2023

卷号：9

期号：1

外文期刊名：GEOMECHANICS AND GEOPHYSICS FOR GEO-ENERGY AND GEO-RESOURCES

收录：SCI-EXPANDED(收录号：WOS:000938235000001)、、EI(收录号：20230913649210)、Scopus(收录号：2-s2.0-85148891706)、WOS

基金：AcknowledgementsThis research is funded by the National Natural Science Foundation of China (42077247, 42107163), the China Postdoctoral Science Foundation (2021M692448, 2022T150483), and the Fundamental Research Funds for the Central Universities. DE acknowledges support from the G. Albert Shoemaker endowment. We appreciate the assistance of Lei Wang in lab.

语种：英文

外文关键词：Enhanced geothermal system (EGS); Hot dry rock; Hydraulic fracturing; Heating-quenching cycles; Permeability; Fracture stability

外文摘要：Fluid injection into enhanced geothermal system (EGS) reservoirs can reactivate subsurface fractures/faults and trigger earthquakes-requiring that frictional stability and permeability evolution characteristics are adequately evaluated. This behavior potentially becomes more complicated when the impacts of temperature and cycled thermal stresses, and the resulted damage accumulation on both stability and transport characteristics are getting involved. We conducted coupled shear-flow experiments on saw-cut fractures recovered from an analog surface outcrop representative of a reservoir at 2450 m in the Gonghe Basin of northwestern China. The rocks were subjected to variable numbers of repeated heating-quenching (25-180-25 degrees C) cycles for shear-flow experiments at an effective stress of similar to 3 MPa and with velocity stepped between 10-1-10-1-10 mu m/s. The smooth fractures return frictional coefficients in the range similar to 0.69 to 0.72 and are little affected by the thermal cycling. The frictional stability parameter (a-b) decreases and the instantaneous permeability increases with an increase in the number of heating-quenching cycles, during which intergranular and intragranular microcracks were generated in fracture surface. The above results indicate that the heating-quenching cycles during hydraulic fracturing of geothermal reservoir could affect both the fracture frictional instability and permeability evolution.