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Log file and GSAS data files for synchrotron study of NaMnF3. Diffraction patterns from synchrotron experiments on NaMnF3. NERC grant: Understanding the D' zone: novel fluoride analogues to MgSiO3 post perovskite NERC grant abstract: The thermal boundary layers of a convecting system control many aspects of its style of convection and thermo-chemical history. For the silicate Earth these boundary layers are the lithosphere, whose low temperature and high rigidity induces slab-style downwellings, and the D' region on the mantle side of the core-mantle-boundary (CMB). The D' region is the source of plume-style convection and regulates heat exchange from the core to the silicate Earth. The lower thermal boundary is made more complex by the existance of a phase transition in the most common mineral in the lower mantle (magnesium-silicate perovskite) which changes the properties of the D' region at the CMB. Unfortunately, most of these properties cannot be measured at the extreme pressures (120 GPa) of stabilisation of the post-perovskite phase. The best chance of constraining them is through a combination of measurements on low-pressure analogue materials (which have the same crystal structure but a different chemical composition) and ab initio simulations of both the analogue and natural systems. We have recently developed a set of ABF3 analogues whose properties are much more similar to MgSiO3 than are those of the CaBO3 analogues currently in use. We propose, therefore, to use these improved fluoride analogues to determine the properties of post-perovskite which control the dynamics of D' (phase diagram, pressure-temperature-volume relations, viscosity, slip systems and thermal diffusivity). These measurements will allow models to be developed which accurately predict the behaviour of the lower thermal boundary layer of the mantle. This will place coinstraints on (1) the heat budget, dynamo power and start of crystallisation of the inner core, (2)the vigour of plumes, (3) the ratio of underside heating to internal heating in the mantle and, (4) the radioactive element budget of the silicate Earth.
The two-phase modeling of water between liquid iron and silicate melt at 50 and 135 gigapascals (corresponding to 3500 and 4200 kelvin) was performed by using ab initio molecular dynamics implemented in the Vienna Ab Initio Simulation Package.
The three-component data are downloaded from CDSN and processed with instrument response removed. The data coverages include sampling in the East Asia, southwest and northwest Pacific.
Data files have .dat extension and can be opened with Notepad or any basic text editor software. Each file contains details of sample name, dimensions (length and diameter). All deformed samples were pre-prepared cylinders of synthetic neighbourite. Each file contains 11 data column as follows: Time (hours); Time (secs); CP (V); Vol (V); Force(V); Temp (V); Disp(V); Euro disp (mm); Furn T (mV); PoreP (mV); Furnace Power where V= Volts, mV= millivolts. The Calibration sheet (specific to the apparatus used) uploaded together with the data files is required to convert V and mV raw data into values of stress, strain, strain rate, confining pressure and temperature.
Input and output files from first-principles calculations to compute the lattice thermal conductivity, elastic properties, and phase stability of various lower mantle minerals. Spreadsheets of processing and final results. Article pre-prints.
This data is described in section 6.4 of the following paper, Three-Field Block Preconditioners for Models of Coupled Magma/Mantle Dynamics by Rhebergen et al DOI:10.1137/14099718X
Tables of characteristic parameters for each model used in paper Agrusta et al. 2014, The effect of metastable pyroxene on the slab dynamics, DOI: 10.1002/2014GL062159 Tables of characteristic parameters for each model used in paper Agrusta et al 2017, Subducting-slab transition-zone interaction: Stagnation, penetration and mode switches, DOI: 10.1016/j.epsl.2017.02.005
High-pressure multi anvil synchrotron data from ID06-LVP at the ESRF. Contains diffraction, radiography, MHz ultrasonic and calibration data from experiments performed to ~ 13 GPa on CaSiO3 perovskite and Ca[Si60Ti40]O3 perovskite samples.
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.
Broadband data collected at the equatorial Mid-Atlantic Ridge from March 2016 to March 2017. From the Grant abstract: We will systematically image the entire length of an oceanic plate, from its birth at the Mid Atlantic Ridge to its oldest formation on the African margin. This is a large-scale focused effort with multiple scales of resolution and sensitivity, from a metre to kilometre scale using seismic and electromagnetic methods. This scale, focus, and interdisciplinary approach will finally determine the processes and properties that make a plate strong and define it. The project will be accomplished through a large, focused international collaboration that involves EU partners (3.5 M euro) and industry (6.4M euro), both already funded.