Friction coefficient and frictional stability (rate & state parameter) data for triaxially compressed direct shear experiments on kaolinite-rich china clay and Mg-montmorillonite fault gouges (<2micron grain size). A total of 19 raw experimental datasets are presented as detailed in the index files: 13 on kaolinite-rich china clay, and 6 on cation-exchanged Mg-Montmorillonite. The raw data files, logged at either 1 or 2Hz, comprise confining pressures, upstream and downstream fluid pressures, force experienced by the direct shear assembly during triaxial compression, and absolute volumes of the confining pressure and fluid pressure reservoirs. Data is provided as measured by gauges in the pressure vessel in Volts, and also as calculated in MPa, kN and mm3. Also presented are the outputs of MATLAB models run to simulate the rate and state parameters k, a, b, dc and f0 for each experiment, with error data presented as 2sigma and standard error values. Parameters were determined using a non-linear least-squares fitting routine with the machine stiffness treated as a fitting parameter (c.f. Noda and Shimamoto, 2009). Data were fit by a single set of state variables (a, b, dc) with a linear detrend. Also presented are the outputs of Specific Thermogravimetric Analyses on kaolinite-rich china clay and Mg-montmorillonite.
Ethiopia experienced severe drought in 2015-16. Many rural communities experienced declines in the performance of their water supply systems. As a result UNICEF commissioned a real-time monitoring and responsive operation and maintenance programme for point source rural water supplies across Central, Northern and Eastern Ethiopia. The water point monitoring survey was coordinated by UNICEF and conducted by World Vision Ethiopia and Oxfam Ethiopia. Data was collected between January and May 2016. Akvo Flow, a mobile survey tool, was used to collect data using questionnaires which were completed by enumerators and uploaded to central servers in near real time. The dataset includes data on functionality, access, usage and water quantity from 5196 rural water points. UNICEF provided the dataset to BGS. BGS reorganised, cleaned, and conducted quality control and analysis of the dataset. A companion paper has been published with more details of the methodology and results of the monitoring survey, https://doi.org/10.1038/s41467-020-14839-3
High frequency (100 Hz) data from two horizontal induction coils measuring the Earth's magnetic field at the Eskdalemuir Observatory in the United Kingdom. The data covers the period from January 2018 to December 2018. Also included are examples of Matlab code and the frequency calibration files to convert to the raw data to SI units. Thumbnail spectrograms and metadata are also supplied.
High frequency (100 Hz) data from two horizontal induction coils measuring the Earth's magnetic field at the Eskdalemuir Observatory in the United Kingdom. The data covers the period from January 2019 to December 2019. Also included are examples of Matlab code and the frequency calibration files to convert to the raw data to SI units. Thumbnail spectrograms and metadata are also supplied.
This document is the drillers log of strata encountered during site investigation work. The log was made in the field during drilling at Prees, Shropshire on 8th to 10th January 2020. The log includes basic information on lithology and drilling equipment used and depths of the individual core runs.
River elevation and catchment area data for major rivers in Calabria, Italy (one river profile in each file). Data were extracted from 1 arc second SRTM (Shuttle Radar Topography Mission) Digital Elevation Models using the Arc GIS hydrology toolbox between October 2015 and October 2019. These river profiles were acquired for fluvial inversion to calculate rock uplift in Calabria.
Data output from the numerical flow modelling in GRL manuscript ""Evidence for the top-down control of lava domes on magma ascent dynamics"", by Marsden, L., Neuberg, J. & Thomas, M., all of University of Leeds. The models were created using the Laminar Flow module in COMSOL Multiphysics v5.4 by L. Marsden. The following files are uploaded: Archive_Reference_Model.txt (Reference flow model: Gas loss function, Initial H2O content = 4.5 wt.% Excess pressure at depth = 10 MPa, Constant corresponding to crystal growth rate = 4e-6 s^-1 ) Archive_High_H2O.txt (Gas loss function, Initial H2O content = 10 wt.% Excess pressure at depth = 10 MPa, Constant corresponding to crystal growth rate = 4e-6 s^-1) Archive_No_Gas_Loss.txt (No gas loss, Initial H2O content = 4.5 wt.% Excess pressure at depth = 10 MPa, Constant corresponding to crystal growth rate = 4e-6 s^-1) Archive_Gamma_Low.txt (Gas loss function, Initial H2O content = 4.5 wt.% Excess pressure at depth = 10 MPa, Constant corresponding to crystal growth rate = 1e-6 s^-1) Archive_Excess_Pressure_0MPa.txt (Gas loss function, Initial H2O content = 4.5 wt.% Excess pressure at depth = 0 MPa, Constant corresponding to crystal growth rate = 4e-6 s^-1) Archive_Excess_Pressure_20MPa.txt (Gas loss function, Initial H2O content = 4.5 wt.% Excess pressure at depth = 20 MPa, Constant corresponding to crystal growth rate = 4e-6 s^-1) The files uploaded include the reference flow model and where a single key parameter has been changed in the flow modelling. We include data where the key parameter is at the upper or lower limit of the values tested. Data are not included where magma ascent is modelled to stall without the extrusion of a lava dome, as a time dependent model is not run in this case. A solution is provided using equilibrium modelling only. The following variables are output, at conduit centre unless specified: Depth (m), Time(s), Ascent velocity (m/s), Bulk Viscosity (Pa s), Crystal Content, Dome height (m), Gas Volume Fraction, Overpressure (Pa), Shear Stress at Conduit Wall (Pa)
The partitioning coefficients of water between iron and silicate melts at 20, 50, 90 and 135 gigapascals (corresponding to 2800, 3500, 3900 and 4200 kelvin) were calculated by using ab initio molecular dynamics and thermodynamic integration techniques. The Gibbs free energy of a series of iron and silicate melts with different concentrations of H2/H2O were calculated. Then the chemical potentials of H2/H2O were derived from the concentration dependent Gibbs free energies at each pressure temperature. The partitioning coefficients can be calculated by equating the chemical potential of H2/H2O in iron and silicate melts. The Weeks-Chandler-Andersen (WCA) system with established thermodynamics was used as the reference.
Geochemical data for the Huainan Basin include Fe speciation data; P speciation data; elemental Al, Fe, P, Mn, Sr data, total organic carbon; C isotope ratios of organic C and carbonates. Geochemical data for the Taoudeni Basin and the Anamikie Basin include Fe speciation data; P speciation data; and elemental P and total organic carbon analyses.
Data supporting 'Effective permeability tensors of three-dimensional numerically grown geomechanical discrete fracture networks with evolving geometry and mechanical apertures', submitted to the Journal of Geophysical Research: Solid Earth. Authors: Robin N Thomas (corresponding, email@example.com), Adriana Paluszny, Robert W Zimmerman. Department of Earth Science and Engineering, Imperial College London. Contents: For each GDFN, the geometry at each growth step. Additionally, for GDFN E, the data shown in the paper (aperture and flow distributions, figures 6 and 7) are provided, including the displacement for the mechanical case, and pressure distributions which were not shown in the manuscript. For the two SDFN sets, the geometry of the four datasets shown in figures 4 and 5 are provided. Notes: - The geometry files are provided in the .3dm format, Rhinocerous' native format (https://www.rhino3d.com/). A free trial of Rhinocerous can be used to explore the files, and can convert them to a range of other CAD file types. - VTK files can be viewed using free software such as Paraview (https://www.paraview.org/). These contain the meshes. - Fracture surface areas reported in the paper are derived from the mesh, rather than the geometry. The mesh approximates the geometry leading to a different surface area than those measured in the geometry (3dm) files. - The SDFN datasets are shown before trimming the parts of fractures which are outside the domain. These parts are trimmed when they are imported to ICGT.