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  • This UKCCSRC (UK Carbon Capture and Storage Research Centre) Call 1 project involved the development, testing and validation of a two-fluid transient flow model for simulating outflow following the failure of high pressure CO2 pipelines is presented. The project made use of experimental data and used experimental data available from other UK/EC funded projects. The model developed accounts for thermal and mechanical non-equilibrium effects during depressurisation by utilising simple constitutive relations describing inter-phase mass, heat and momentum transfer in terms of relaxation to equilibrium. Pipe wall/fluid heat exchange on the other hand is modelled by coupling the fluid model with a finite difference transient heat conduction model. This paper describes the model, the details of its numerical solution and its validation as well as parametric analysis of relevant parameters. http://www.sciencedirect.com/science/article/pii/S1750583614002394, DOI: 10.1016/j.ijggc.2014.08.013. UKCCSRC grant UKCCSRC-C1-07.

  • These data are the recorded outcomes of binary male choice experiments. Teleopsis dalmanni males were able to choose to mate with either a large or a small female. Individuals were taken from laboratory stock populations. Also included is information on male genotype indicating if he is a carrier of a sex-ratio distorting or nondistorting X chromosome, and a calculation of male preference. The second dataset additionally contains measures of male eyespan and thorax length obtained by measuring images. Full details about this nonGeographicDataset can be found at https://doi.org/10.5285/d6c36f89-07f1-4bcc-96a0-f5302fd3ccec

  • The raw data contain genotype information for offspring collected from controlled crosses of Teleopsis dalmanni. Parents were taken from laboratory stock populations. Offspring genotypes were assigned by sizing a microsatellite, which distinguishes sex-ratio distorting and nondistorting X chromosomes. Also included is information on offspring sex and food treatment. The processed data summarises genotype counts by collection date and cage id (date/food treatment/cage). Also included is a fitness calculation for each genotype in each cage. Full details about this nonGeographicDataset can be found at https://doi.org/10.5285/71529a64-6c1b-4c8f-ae3f-7c4870efd976

  • The data contain phenotype measures of Teleopsis dalmanni males. Individuals were all taken from a laboratory stock population. Individuals carried either a nondistorting wildtype X chromosome or a sex-ratio distorting X chromosome. Data were obtained by measuring images of testes, accessory glands, thorax and eyespan, and direct counts of fertilised (hatched) and unfertilised egg. Full details about this nonGeographicDataset can be found at https://doi.org/10.5285/6e4c5823-35f5-4c90-b616-2190d87c0391

  • Processed SAR interferograms for the Wells, Nevada earthquake. Grant abstract: How do earthquakes happen? Understanding the nature of earthquakes is a key fundamental question in Geociences that holds many implications for society. Earthquakes are typically associated with a sudden release of energy that has slowly accumulated over hundreds to thousands of years, being strongly controlled by friction in faults buried several kilometers beneath our feet under quite extreme conditions. For example, the amount of heat produced in just a few seconds is such that it can dramatically change the nature of the fault zone near the sliding surface. Moreover, there is abundant evidence of substantial frictional weakening of faults (i.e., fault strength weakens with increasing slip or slip rate) during earthquakes. However, there are still many open questions related to earthquake source processes: How similar are earthquakes in different temperature-pressure conditions? What is the earthquake's energy budget, which controls the intensity of ground motions? What are the physical mechanisms responsible for fault weakening? Recent progress in seismological imaging methods, theoretical fracture mechanics and rupture dynamics simulations can help solve these questions. Huge volumes of freely available seismic and geodetic data from around the world now allow the routine calculation of earthquake models where earthquakes are typically described as single space-time points. Time is now ripe for systematically building robust, more detailed seismic models bearing information on earthquake's physics by using recently developed sophisticated modelling tools along with high-quality images of the 3-D Earth's interior structure enabled by high performance computing facilities. Moreover, it is now possible to model ruptures theoretically in detail using both analytical fracture mechanics calculations and numerical rupture dynamics simulations, and, for example, estimate the fault temperature during the rupture process, which is the most direct way to quantify friction. However, systematic quantitative links between these calculations and seismological observations are still lacking. This project addresses these issues through a coordinated effort involving seismology and rock mechanics aiming at estimating fault temperature rise during earthquakes from new macroscopic seismic source models. We will use advanced seismic source imaging methods to build a new set of robust kinematic, static and dynamic earthquake source parameters for a large selected set of global earthquakes (e.g., average fault length, width, rupture speed and time history, stress drop, radiated and fracture energy). These solutions will then be used as input parameters to estimate fault temperature using analytical and numerical rupture dynamics calculations. This will lead to an improved understanding of how local fault processes occurring at scales from few microns to tens of centimetres translate into macroscopic seismological properties, how energy is partitioned during earthquakes and which are the mechanisms responsible for fault weakening. Ultimately this project will shed new light on many basic questions in earthquake science such as the similarity of earthquakes in different P-T conditions and the potential geological record left by ruptures (e.g., melt). More broadly, this project will benefit hazard models and any studies relying on accurate earthquake source parameters such as studies in seismic tomography, active tectonics and microseismicity (e.g., associated with hydraulic fracturing).

  • Observed global seismograms used to study earthquakes in the Azores. The seismograms have been processed and then have been used to perform source inversions of the events.

  • Synthetic seismic waveforms computed using the spectral element method for 1-D and 3-D Earth models for a variety of scenarios of structures in the deep Earth's interior.

  • This dataset contains VASP runs performed on ARCHER to calculate the electrical and thermal conductivities of pure iron and iron alloys at Earth's core conditions using density functional theory with the Kubo-Greenwood formulation. Data are available for both the solid and the liquid phase characterising the inner and outer core respectively. Also included in the dataset the runs for computing the lattice contribution to the electrical resistivity of magnetic bcc iron at ambient pressure and two low temperatures and for computing the melting curve of fcc nickel. These data were also used for the modelling of the geodynamo and the thermal history of the Earth, to calculate the transport properties for silicon-oxygen-iron mixtures and to confirm the saturation of electrical resistivity of solid iron at Earth’s core conditions. The results from this dataset showed that both conductivities are much larger than previously thought with important implications for the geodynamo and the thermal history of the Earth, benefitting the geodynamo community. The results of our research have been recently confirmed by new experimental results obtained at Earth's core conditions. Further details can be found in Alfè et al. (2012); Pozzo et al. (2012, 2013a, 2013b, 2014, 2016); Gubbins et al. (2015); Davies et al. (2015). NERC Grant is NE/H02462X/1.

  • Multi-decadal time series of groundwater levels were compiled by the authors from records of observation wells initiated and maintained by government departments and research institutions in nine countries in sub-Saharan Africa. The pan-African collation of these hydrographs was initiated at the 41st Congress of the International Association of Hydrogeologists (IAH) in Marrakech (Morocco) on 14th September 2014. All records were subjected to a rigorous review by the authors during which the integrity, continuity, duration and interpretability of records were evaluated. This process included dedicated workshops in Benin, Tanzania, and Uganda, and records failing these tests were discarded from the analysis. Procedures included taking of the first time derivative to identify anomalous spikes in records commonly associated with errors of data-entry. Where multiple records in same geographic and climate zone were available (e.g. Benin, South Africa) we prioritized records remote from potential areas of intensive abstraction. Statistical clustering of records was also used in the Limpopo Basin of South Africa to identify the representativity of employed records at Modderfontein and Sterkloop.

  • Rare earth element, major and minor element, and iron speciation data for nine independent sections in the Nama Group, described in detail in Wood et al., 2015, Precambrian Research, and Tostevin et al., 2016, Nature Communications. Additional data for Zebra River section include sulfur isotopes from carbonate associated sulfate (published in Tostevin et al, 2017, Precambrian Research); Uranium isotope data for carbonates (published in Tostevin et al., 2019, EPSL); Calcium isotope data for carbonates (unpublished).