Unfortunately this page does not have a mobile or narrow screen view. Please switch to a desktop computer or increase the size of your browser. For tablets try flipping the screen.
Data Publication
Frictional slip weakening and shear-enhanced crystallinity in simulated coal fault gouges at subseismic slip rates
Liu, Jinfeng | Hunfeld, Luuk Bernd
YoDa Data Repository, Utrecht University, Netherlands
(2020)
We report seven velocity stepping (VS) and one slide-hold-slide (SHS) friction experiments performed on simulated fault gouges prepared from bituminous coal, collected from the upper Silesian Basin of Poland. These experiments were performed at 25-45 MPa effective normal stress and 100 ℃, employing sliding velocities of 0.1-100 μm/s, using a conventional triaxial apparatus plus direct shear assembly. All samples showed marked slip weakening behaviour at shear displacements beyond ~1-2 mm, from a peak friction coefficient approaching ~0.5 to (near) steady state values of ~0.3, regardless of effective normal stress or whether vacuum dry flooded with distilled (DI) water at 15 MPa pore fluid pressure. Analysis of both unsheared and sheared samples by means of microstructural observation, micro-area X-ray diffraction (XRD) and Raman spectroscopy suggests that the marked slip weakening behaviour can be attributed to the development of R-, B- and Y- shear bands, with internal shear-enhanced coal crystallinity development. The SHS experiment performed showed a transient peak healing (restrengthening) effect that increased with the logarithm of hold time at a linearized rate of ~0.006. We also determined the rate-dependence of steady state friction for all VS samples using a full rate and state friction approach. This showed a transition from velocity strengthening to velocity weakening at slip velocities >1 μm/s in the coal sample under vacuum dry conditions, but at >10 μm/s in coal samples exposed to DI water at 15 MPa pore pressure. This may be controlled by competition between dilatant granular flow and compaction enhanced by presence of water. Together with our previous work on frictional properties of coal-shale mixtures, our results imply that the presence of a weak, coal-dominated patch on faults that cut or smear-out coal seams may promote unstable, seismogenic slip behaviour, though the importance of this in enhancing either induced or natural seismicity depends on local conditions. The data is provided in a folder with 10 subfolders for 10 experiments/samples, including friction, XRD and Raman data. Detailed information about the files in these subfolders as well as information on how the data is processed is given in the explanatory file Fan-et-al-2020-Data-Description.pdf. Contact person is Dr. Jinfeng Liu - Sun Yat-Sen University- liujinf5@mail.sysu.edu.cn
Keywords
Originally assigned keywords
Corresponding MSL vocabulary keywords
MSL enriched keywords
MSL original sub domains
MSL enriched sub domains i
Source publisher
YoDa Data Repository, Utrecht University, Netherlands
DOI
10.24416/UU01-48I5DA
Authors
Liu, Jinfeng
0000-0002-6444-9427
School of Earth Sciences and Engineering, Sun Yat-Sen University; Guangdong Provincial Key Lab of Geodynamics and Geohazards, Sun Yat-Sen University, Zhuhai, China; Southern Marine Science and Engineering Guangdong Laboratory, Zhuhai, China;
Hunfeld, Luuk Bernd
0000-0001-9250-414X
Utrecht University;
Contributers
Fan, Caiyuan
DataCollector
0000-0002-0413-8467
School of Earth Sciences and Engineering, Sun Yat-Sen University;
Fan, Caiyuan
Researcher
0000-0002-0413-8467
School of Earth Sciences and Engineering, Sun Yat-Sen University;
Liu, Jinfeng
DataCollector
0000-0002-6444-9427
School of Earth Sciences and Engineering, Sun Yat-Sen University; Guangdong Provincial Key Lab of Geodynamics and Geohazards, Sun Yat-Sen University, Zhuhai, China; Southern Marine Science and Engineering Guangdong Laboratory, Zhuhai, China;
Liu, Jinfeng
ProjectLeader
0000-0002-6444-9427
School of Earth Sciences and Engineering, Sun Yat-Sen University; Guangdong Provincial Key Lab of Geodynamics and Geohazards, Sun Yat-Sen University, Zhuhai, China; Southern Marine Science and Engineering Guangdong Laboratory, Zhuhai, China;
Liu, Jinfeng
Researcher
0000-0002-6444-9427
School of Earth Sciences and Engineering, Sun Yat-Sen University; Guangdong Provincial Key Lab of Geodynamics and Geohazards, Sun Yat-Sen University, Zhuhai, China; Southern Marine Science and Engineering Guangdong Laboratory, Zhuhai, China;
Hunfeld, Luuk Bernd
Researcher
0000-0001-9250-414X
Utrecht University;
Spiers, Christopher James
Researcher
0000-0002-3436-8941
Utrecht University;
Experimental rock deformation/HPT-Lab (Utrecht University, The Netherlands)
HostingInstitution
Utrecht University;
of Earth Sciences and Engineering (Sun Yat-Sen University), School
HostingInstitution
Sun Yat-Sen University;
Liu, Jinfeng
ContactPerson
0000-0002-6444-9427
School of Earth Sciences and Engineering, Sun Yat-Sen University; Guangdong Provincial Key Lab of Geodynamics and Geohazards, Sun Yat-Sen University, Zhuhai, China; Southern Marine Science and Engineering Guangdong Laboratory, Zhuhai, China;
References
Hunfeld, L. B., Niemeijer, A. R., & Spiers, C. J. (2017). Frictional Properties of Simulated Fault Gouges from the Seismogenic Groningen Gas Field Under In Situ P–T ‐Chemical Conditions. Journal of Geophysical Research: Solid Earth, 122(11), 8969–8989. Portico. https://doi.org/10.1002/2017jb014876
10.1002/2017JB014876
References
Contact
Liu, Jinfeng
School of Earth Sciences and Engineering, Sun Yat-Sen University; Guangdong Provincial Key Lab of Geodynamics and Geohazards, Sun Yat-Sen University, Zhuhai, China; Southern Marine Science and Engineering Guangdong Laboratory, Zhuhai, China;
Citiation
Liu, J., & Hunfeld, L. B. (2020). Frictional slip weakening and shear-enhanced crystallinity in simulated coal fault gouges at subseismic slip rates. Utrecht University. https://doi.org/10.24416/UU01-48I5DA
Collection Period
2016-10-01 - 2020-01-31
Geo location(s)
49.96072880335346, 15.384399613612231, 51.57806093491139, 21.53674470471674
Coal samples were collected from Brzeszcze Mine (Seam 364), in the Upper Silesian Basin of Poland, Poland