Acoustic emissions (AE) and ultrasonic wave velocity data recorded during a series of high temperature thermal cracking experiments by Daoud et al., in the Rock and Ice Physics Laboratory of the University College London. The data gives the time and magnitude of AE output which were recorded contemporaneously whilst cyclically heating three rock types (A Slaufrudalur Granophyre, A Santorini Andesite and a Seljadalur Basalt). The ultrasonic wave velocity data was recorded pre- and post- heating. The data acquisition was permitted using a rock placed within an acoustic wave guide placed inside a high temperature furnace.

Collection of data from the PhD Thesis "Thermo-mechanical loading of intact rock and discontinuities" by J Woodman. This collection of data includes raw logged .csv datafiles of uniaxial compression testing and triaxial compression testing on intact synthetic compositions, as well as intact and discontinuous specimens of Thornhill Rock and Midgley Grit at both ambient temperatures, and temperatures up to 100°C.

This data has been recorded during a triaxial rock deformation experiment where a Lanhelin granite samples was subjected to controlled shear failure. The data consists of mechanical data (load, displacement, confining pressure, strain gauge data) and acoustic data necessary to reproduce the seismic tomography presented in 'Rupture energetics in crustal rock from laboratory-scale seismic tomography' by Aben, Brantut, Mitchell and David [2019], Geophysical Research Letters. Acoustic data contains AE source locations and arrival times, sensor locations, arrival times of active acoustic surveys.

Unconfined compressive strength data for rocks from TilTil and ElTeniente mines in Chile, plus basic index tests (porosity, density) and Elastic wave velocity for selected samples. Laboratory data collected as part of NERC grant NE/W00383X/1:Geological safety and optimisation in mining operations: towards a new understanding of fracture damage, heterogeneity and anisotropy.

The mechanical data (loads, displacements) recorded during double torsion experiments on samples of 6 shale materials and a sandstone. These experiments were conducted on the I12 beamline, Diamond Light Source, Harwell as part of beamtimes EE13824-1 and EE13824-2 between 26/02/17 and 03/03/17. The data were collected using the standard double-torsion technique, with a load cell behind the actuator recording applied force. The method and results are described in detail by Chandler et al, (2018,submitted) "Correlative optical and X-ray imaging of strain evolution during Double Torsion Fracture Toughness measurements in shale" The data was collected with the aim of correlating local deformation around a progressing fracture (through X-Ray and optical imaging) with recorded mechanical data from the loading system. The data was collected by M. Chandler, A-L Fauchille, J. Mecklenburgh, H. K. Kim and L. Ma, and was processed by M. Chandler and R. Rizzo. The complete dataset is present.

Datafiles are from a suite of frictional velocity step experiments on clay-bearing fault gouges, at elevated temperatures up to 180°C. The aim was to test if varying temperature reduces the stability of clay-rich faults, measured by the rate and state friction parameter (a-b). Data were collected in the Rock Deformation Laboratory at the University of Liverpool between Oct 2021 to May 2022 by Dr. Isabel Ashman, as part of her NERC EAO DTP studentship. The datafiles are text files of both the raw voltage and calibrated measurements from triaxial deformation experiments. The stability of synthetic kaolinite clay-bearing fault gouges was found to decrease systematically with elevated temperatures commensurate with those found at typical earthquake depths. In materials containing 25-50% clay, the stability of slip decreased with increasing temperature so that the gouges displayed unstable slip at temperatures between 100 and 180°C. At room temperature the same materials showed stable slip and velocity strengthening characteristics. The reduction in stability with increasing temperature coincides with a greater degree of compaction observed in the gouge microstructure and is inferred to result from progressive loss of water adsorbed on the clay surfaces. These results indicate that clay-bearing fault rocks can nucleate unstable slip at conditions common to the clay-bearing brittle crust; a result that adds to the observations of mature clay-bearing faults in nature that can nucleate and propagate earthquakes.

The dataset contains point load test data of salt samples collected from the Northwich Halite Member at the Winsford Mine in Cheshire, UK. Each sample was tested in an unconfined state using a point load testing apparatus, in which compressive force was applied through two opposing conical platens until failure occurred. All tests were conducted in the Rock Mechanics and Physics Laboratory at the British Geological Survey, Keyworth, UK. The dataset is compiled into a single Microsoft Excel file, with each row representing an individual test. For each test, measurements of sample length, diameter, and peak load are provided, along with calculated point load strength indices and estimates of unconfined compressive strength.

This dataset contains raw data from synthetic and experimental velocity steps analyzed using the MATLAB routine ‘steadystate.m’, as presented by Giacomel, P., Faulkner, D.R., Lambert, V., Allen, M.J (2024): ‘steadystate: A MATLAB-based routine for determining steady-state friction conditions in the framework of rate- and state- friction analysis’ – GSA, Geosphere. The data is provided in .zip folder containing the Velocity Steps and the outputs from steadystate.m, along with the scripts used to generate the figures shown in the Manuscript and Supplementary Material. The folder ‘Velocity_Steps’ notably contains the complete suite of mechanical data (subfolder ‘Mechanical_Data), the modelled rate- and state- friction parameters (subfolder ‘Modelled_RSF_Parameters SlipLaw’) obtained by assuming steady state at different displacements, as well as the linear detrended end members (i.e., at short to large displacements) fitted via inverse modelling (subfolder ‘Detrended_Velocity_Steps + Fit-Inversions’). Such observations were foundational for the development of the steadystate.m routine. Each subfolder is accompanied by a README.txt file that reports on the link between the raw .txt data with the MATLAB scripts generating the associated figures. For the sepiolite fault gouge used during the friction velocity steps, please refer to: Sánchez-Roa, C., Jiménez-Millán, J., Abad, I., Faulkner, D. R., Nieto, F., and García-Tortosa, F. J., 2016, Fibrous clay mineral authigenesis induced by fluid-rock interaction in the Galera fault zone (Betic Cordillera, SE Spain) and its influence on fault gouge frictional properties: Applied Clay Science, v. 134, p. 275-288.

This dataset contains raw mechanical measurements of standard uniaxial tests in 1) tension; 2) compression; 3) compression with creep deformation (load hold); 4) compression with creep and mechanical oscillations. The data is used by Schaefer et al., 2023, (https://doi.org/10.55575/tektonika2023.1.1.10). Experiments consisted of 1) standard Uniaxial Compressive strength tests; 2) Brazilian tensile strength tests; 3) Creep tests in compression and tension; 4) Creep and mechanical oscillations tests in compression and tension. For experiments in 1 in compression, a rock cylinder of 20x40 mm (diameter x height) is loaded at a constant deformation rate in a uniaxial press, for each test type until 1) failure; 3) a target stress that is then held constant for 5h before moving to a different target stress and repeating the process; and 4) to a target stress that is then held for 30 mins before inducing stress oscillations for 40 minutes. The stress is then held constant at the end of oscillations for another 30 mins. Target stresses corresponded to 50; 60 and 70% of the average compressive strength measured in test type 1. For experiments in 1), 3) and 4) in tension, a rock disc of 40x20 mm (diameter x height) is loaded at a constant deformation rate in a uniaxial press under the same stressing configurations as in compression. More details of the methods can be found in the publication Schaefer et al., 2023. Volcanic domes and edifices are inherently unstable owing to their structure and rapid emplacement/growth, further enhanced by both mechanical and thermal variations due to the movement of magma. Understanding the long-term mechanical response and fatigue of their rock constituents is thus key to understanding their stability. Experimental datasets can help quantify the amount of deformation that rocks can sustain before failure, helping us to understand possible rock failure events at larger scale at volcanoes. All data were collected at the University of Liverpool and analysed at the University of Liverpool, UK, at the USGS, USA and LMU Munich, Germany. All samples were collected at Unzen volcano, Japan. Experiments and data analysis were carried in 2021 and 2022.

The dataset contains unconfined compressive strength data of salt samples collected from the Northwich Halite Member at the Winsford Mine in Cheshire, UK. Each sample was unconfined and deformed under standard uniaxial stress conditions, where the primary principal stress corresponds to the axial stress and the intermediate and minimum principal stresses are equal to 0. Each sample was axially compressed using either a constant strain rate of 1e-5 per second or a constant loading rate of 200 N/s. The tests were completed using a servo-controlled stiff load frame in the Rock Mechanics and Physics Laboratory at the British Geological Survey, Keyworth UK. The data are separated into individual Microsoft Excel files, with each file representing a single test. Each file contains time, force, stress, displacement, and strain data.