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  • Data supporting the publication: Robin N. Thomas, Adriana Paluszny, Robert W. Zimmerman, 2017. Quantification of fracture interaction using stress intensity factor variation maps. Journal of Geophysical Research: Solid Earth [DOI: 10.1002/2017JB014234]. Each sheet contains the data used in each figure, covering method validation, stress intensity factor perturbations, and data used to create fracture interaction maps. The data were created using the Imperial College Geomechanics Toolkit.

  • The spreadsheet gathers the data collected during a brine:CO2 flow-through experiment conducted on a synthetic sandstone core sample to present the capabilities of a novel 'multiflow experimental rig for CO2 experiments' designed and assembled at the National Oceanography Centre, Southampton. The test was configured to assess geophysical monitoring techniques in shallow tight (North Sea-like) CO2 storage sandstone reservoirs. The tests were conducted in the rock physics laboratory at the National Oceanography Centre, Southampton, during 2015, as part of the DiSECCS project with funding from the United Kingdom's Engineering and Physical Sciences Research Council (EPSRC grant EP/K035878/1) and the Natural Environment Research Council (NERC). The experiment was a steady state brine-CO2 flow-through test to replicate CO2 geosequestration conditions and evaluate geophysical monitoring techniques. The confining and pore pressure conditions were similar to those estimated for shallow North Sea - like storage reservoirs, but simulating inflation/depletion cyclic scenarios for increasing brine:CO2 fractional flow rates. The data include ultrasonic P- and S-wave velocities and their respective attenuation factors, axial strains, and electrical resistivity; also relative permeability to both fluids (CO2 and brine) is displayed as a function of pore volume times, associated to increasing CO2 to brine contents in the sample.

  • Report summarising the contents of the seismic analysis toolbox produced during the DiSECCS project. The toolbox comprises an online library of seismic software developed and utilised in the project, and presented in a form that other practitioners can utilise and tailor to their own specific needs. The toolbox include software for the measurement and characterisation of thin CO2 layers by spectral and attenuation analysis, fracture characterisation via wavelet coda analysis, novel rock physics algorithms and a summary of new laboratory analyses.

  • The spreadsheet gathers the data collected during an experiment conducted on a Utsira Sand formation core sample to complements and constrains existing geophysical monitoring surveys at Sleipner and, more generally, improves the understanding of shallow weakly-cemented sand reservoirs. The tests were conducted in the rock physics laboratory at the National Oceanography Centre, Southampton, during 2016, as part of the DiSECCS project with funding from the United Kingdom’s Engineering and Physical Sciences Research Council (EPSRC grant EP/K035878/1) and the Natural Environment Research Council (NERC). The experiment was a steady state brine-CO2 flow-through test to simultaneously evaluate ultrasonic waves, electrical resistivity (converted into pore fluid distribution) and mechanical indicators during CO2 geosequestration in shallow weakly-cemented reservoirs. The confining and pore pressure conditions were similar to those estimated for Sleipner (North Sea – like storage reservoirs), but simulating inflation/depletion cyclic scenarios for increasing brine:CO2 fractional flow rates. The data include primary ultrasonic wave velocities and attenuation factors, axial and radial strains, and electrical resistivity. Also, we provide a velocity-saturation relationship of practical importance to CO2 plume monitoring, obtained from the inversion of ultrasonic velocity and attenuation data and extrapolation of results to field-scale seismic-frequencies using a new rock physics theory. The dataset is linked to this publication: http://www.sciencedirect.com/science/article/pii/S1750583617306370.

  • EPSRC project EP/K035878/1 - DiSECCS research has focussed on developing advanced seismic monitoring tools and combining these with social science research to identify key factors in establishing trust and confidence in the storage system.This report presents insights into and recommendations for the monitoring systems and protocols required to maintain the integrity of storage reservoirs suitable for large-scale CO2 storage and for obtaining a social licence to operate a CCS project.

  • 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, robin.thomas11@imperial.ac.uk), 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.

  • EPSRC project EP/K035878/1 - Report summarising scientific findings from Work Packages 1 to 4 of the DiSECCS project. These include advanced seismic methods for assessing pressure changes and fluid flow processes in a reservoir rock, experimental rock physics and public perceptions for CCS and analogue activities.

  • "This data was compiled for the paper "Self-similarity of seismic moment release to volume change scaling for volcanoes: a comparison with injection-induced seismicity", that has been accepted for publication in Geophysical Research Letters. It is a compilation of literature values of volume changes and associated total seismic moment releases for many injection-induced earthquake sequences. It also includes a number of total moment releases and volume changes from volcanic sequences that were calculated for the study from published earthquake catalogues. This work was conducted to examine the response of the shallow crust to volume changes in the two different contexts, make the comparison between them, and discuss why the response is similar or dissimilar. The data consists of two tables. For the fluid injection data the table lists the project name, the approximate dates, the source, the type of operation, and naturally the volume and total seismic moment release. For the volcanotectonic sequences, it lists the name of the eruption/intrusion, the dates, volume change, and moment release. Also included in both tables are the seismic efficiency (functionally the ratio of moment releasee to volume change, see Hallo et al., 2014) and seismogenic index (another measure of the response of the crust to a volume change, see Shapiro et al., 2010). Aki, K. (1965). Maximum likelihood estimate of b in the formula log N = a-bM and its confidence. Bulletin of Earthquake Research Institute of the University of Tokyo, 43, 237–239. Cao, A., & Gao, S. S. (2002). Temporal variation of seismic b -values beneath northeastern Japan island arc Geophysical Research Letters, 29(9), 48-1-48–3. https://doi.org/10.1029/2001gl013775 Hallo, M., Oprsal, I., Eisner, L., & Ali, M. Y. (2014). Prediction of magnitude of the largest potentially induced seismic event. Journal of Seismology, 18(3), 421–431. https://doi.org/10.1007/s10950-014-9417-4 Shapiro, S. A., Dinske, C., Langenbruch, C., & Wenzel, F. (2010). Seismogenic index and magnitude probability of earthquakes induced during reservoir fluid stimulations. Leading Edge, 29(3), 304–309. https://doi.org/10.1190/1.3353727 "

  • The spreadsheet gathers the data collected during a brine:CO2 flow-through experiment conducted on a weakly-cemented synthetic sandstone core sample using the multiflow experimental rig for CO2 experiments, designed and assembled at the National Oceanography Centre, Southampton. The test was configured to assess geophysical monitoring and deformation of reservoirs subjected to CO2 injection in shallow weakly-cemented (North Sea-like, e.g., Sleipner) CO2 storage sandstone reservoirs. The tests was conducted in the rock physics laboratory at the National Oceanography Centre, Southampton, during 2015-2016, as part of the DiSECCS project with funding from the United Kingdom’s Engineering and Physical Sciences Research Council (EPSRC grant EP/K035878/1) and the Natural Environment Research Council (NERC). The experiment was a steady state brine-CO2 flow-through test in which realistic shallow CO2 geosequestration conditions were simulated, to related geophysical signatures to the hydrodynamic and geomechanical behaviour of the rock sample. The confining and pore pressure conditions were similar to those estimated for shallow North Sea Sleipner-like, storage reservoirs, but simulating inflation/depletion cyclic scenarios for increasing brine:CO2 fractional flow rates. The data include ultrasonic P- and S-wave velocities and their respective attenuation factors, axial, radial and volumetric strains, and electrical resistivity; also relative permeability to both fluids (CO2 and brine) is displayed as a function of pore volume times, associated to increasing CO2 to brine contents in the sample.

  • A brief description of ten core plug samples collected from borehole GGC01 (Glasgow, United Kingdom) is provided, as well as for twelve 15-50 g cuttings samples from 1m intervals within borehole GGA08. Samples were also collected from borehole GGA02 but not used for further analyses. Data comprise results from geomechanical tests, permeability and porosity measurements, and X-Ray Diffraction analyses performed on drillcore samples of sandstones, siltstones, mudstones and coals from eleven depth intervals within the GGC01 borehole. Geomechanical data include triaxial compressional strength, tensile strength, and frictional strength. Frictional strength data was also collected for cuttings samples of sandstones, siltstones, mudstones and coals from the GGA08 borehole. In total twenty-three tensile strength tests were performed on ten sampled intervals, and seven porosity measurements pre-and post-failure were taken. Nine triaxial compressive strength tests and twenty-one frictional strength tests were performed, with permeability measured both before and after failure or shear respectively. From compressive strength tests we also determined the Young’s modulus and Poisson’s ratio. Samples and data are derived from the UK Geoenergy Observatories Programme funded by the UKRI Natural Environment Research Council and delivered by the British Geological Survey.