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Journal articleMorgan JV, Warner MR, Collins GS, et al., 2011,
Full waveform tomographic images of the peak ring at the Chicxulub impact crater
, Journal of Geophysical Research, Vol: 116Peak rings are a feature of large impact craters on the terrestrial planets and are generally believed to be formed from deeply buried rocks that are uplifted during crater formation. The precise lithology and kinematics of peak ring formation, however, remains unclear. Previous work has revealed a suite of bright inward-dipping reflectors beneath the peak ring at the Chicxulub impact crater and that the peak ring was formed from rocks with a relatively low seismic velocity. New 2D full-waveform tomographic velocity images show that the uppermost lithology of the peak ring is formed from a thin (~100-200 m thick) layer of low-velocity (~3000-3200 m/s) rocks. This low-velocity layer is most likely to be composed of highly porous, allogenic impact breccias. Our models also show that the change in velocity between lithologies within and outside the peak ring is more abrupt than previously realized and occurs close to the location of the dipping reflectors. Across the peak ring, velocity appears to correlate well with predicted shock pressures from a dynamic model of crater formation, where the rocks that form the peak ring originate from uplifted basement that has been subjected to high shock pressures (10-50 GPa), and lie above downthrown sedimentary rocks that have been subjected to shock pressures of < 5 GPa. These observations suggest that low-velocities within the peak ring may be related to shock effects and that the dipping reflectors underneath the peak ring might represent the boundary between highly-shocked basement and weakly-shocked sediments.
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Journal articleFarrell PE, Piggott MD, Gorman GJ, et al., 2011,
Automated continuous verification for numerical simulation
, Geoscientific Model Development, Vol: 4, Pages: 435-449 -
Journal articleMitchell AJ, Allison PA, Gorman GJ, et al., 2011,
Tidal circulation in an ancient epicontinental sea: The Early Jurassic Laurasian Seaway
, Geology, Vol: 39, Pages: 207-210, ISSN: 0091-7613 -
Conference paperPiotrowski M, Sloan TM, Mewsissen M, et al., 2011,
Optimisation and parallelisation of the partitioning around medoids function in R
, Pages: 707-713 -
Journal articleMaddison JR, Marshall DP, Pain CC, et al., 2011,
Accurate representation of geostrophic and hydrostatic balance in unstructured mesh finite element ocean modelling
, OCEAN MODELLING, Vol: 39, Pages: 248-261, ISSN: 1463-5003- Author Web Link
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- Citations: 11
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Journal articleChen X, Navon IM, Fang F, 2011,
A dual weighted trust-region adaptive POD 4D-Var applied to a Finite-Element shallow-water Equations Model
, International Journal for Numerical Methods in Fluids, Vol: 65, Pages: 520-541 -
BookAllison PA, Bottjer DJ, 2011,
Taphonomy: Process And Bias Through Time (Volume 32 in the Topics in Geobiology series)
, Publisher: Springer, ISBN: 978-90-481-8642-6 -
Journal articleWuennemann K, Collins GS, Weiss R, 2010,
IMPACT OF A COSMIC BODY INTO EARTH'S OCEAN AND THE GENERATION OF LARGE TSUNAMI WAVES: INSIGHT FROM NUMERICAL MODELING
, REVIEWS OF GEOPHYSICS, Vol: 48, ISSN: 8755-1209- Author Web Link
- Open Access Link
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- Citations: 32
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SoftwarePain C, Allison P, Aristodemou E, et al., 2010,
Fluidity
, London, Publisher: Applied Modelling and Computation Group (AMCG), Imperial College London -
Journal articleCole KE, Waters KE, Fan X, et al., 2010,
Combining Positron Emission Particle Tracking and image analysis to interpret particle motion in froths
, MINERALS ENGINEERING, Vol: 23, Pages: 1036-1044, ISSN: 0892-6875- Author Web Link
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- Citations: 11
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Journal articleMorris G, Neethling SJ, Cilliers JJ, 2010,
The effects of hydrophobicity and orientation of cubic particles on the stability of thin films
, MINERALS ENGINEERING, Vol: 23, Pages: 979-984, ISSN: 0892-6875- Author Web Link
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- Citations: 26
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Book chapterPavlidis D, Aristodemou E, Gomes JLMA, et al., 2010,
Numerical Simulation of Air Flows in Street Canyons Using Mesh-Adaptive LES
, Direct and large-eddy simulation VII, Editors: Armenio, Geurts, Fröhlich, Publisher: Springer Verlag, ISBN: 9789048136513This book is of interest to scientists and engineers both at an early level in their career as well as at more senior levels.
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Journal articleMunday DR, Marshall DP, Piggott MD, 2010,
Idealised flow past an island in a dynamically adaptive finite element model
, OCEAN DYNAMICS, Vol: 60, Pages: 835-850, ISSN: 1616-7341- Author Web Link
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- Citations: 6
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Journal articleJackson MD, 2010,
Multiphase electrokinetic coupling: Insights into the impact of fluid and charge distribution at the pore scale from a bundle of capillary tubes model
, JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH, Vol: 115, ISSN: 2169-9313- Author Web Link
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- Citations: 82
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Conference paperDavison TM, Collins GS, Ciesla F, et al., 2010,
Cumulative impact heating of planetesimals
, 73rd Annual Meeting of the Meteoritical-Society, Publisher: Wiley-Blackwell, Pages: A43-A43, ISSN: 1086-9379 -
Journal articleDavison TM, Collins GS, Ciesla FJ, 2010,
Numerical modelling of heating in porous planetesimal collisions
, ICARUS, Vol: 208, Pages: 468-481, ISSN: 0019-1035- Author Web Link
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- Citations: 90
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Conference paperPasek MA, Collins GS, Carter EA, et al., 2010,
SHOCKED QUARTZ IN A FULGURITE
, 73rd Annual Meeting of the Meteoritical-Society, Publisher: WILEY-BLACKWELL PUBLISHING, INC, Pages: A163-A163, ISSN: 1086-9379 -
Conference paperLamb A, Gorman G, Gosselin O, et al., 2010,
Coupled Deformation and Fluid Flow in Fractured Porous Media using Dual Permeability and Explicitly Defined Fracture Geometry
, 72nd EAGE Conference & ExhibitionWe present a numerical scheme which combines the dual permeability method (DPM) and the extended finite element method (XFEM) to simulate coupled deformation and fluid flow in fractured porous media. The scheme incorporates spatial variability in fracture properties without requiring the fracture to be discretized or aligned with the computational mesh. DPM is used to describe the fluid flow interaction between the porous matrix and fractures, whilst XFEM is used to address the discontinuous displacement field within elements which intersect fractures. The method is strongly coupled and solves the stress and flow equations simultaneously for each time increment.
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Journal articleSouthern J, Gorman GJ, Piggott MD, et al., 2010,
Simulating cardiac electrophysiology using anisotropic mesh adaptivity
, Journal of Computational Science, Vol: 1, Pages: 82-88The simulation of cardiac electrophysiology requires small time steps and a fine mesh in order to resolve very sharp, but highly localized, wavefronts. The use of very high resolution meshes containing large numbers of nodes results in a high computational cost, both in terms of CPU hours and memory footprint. In this paper an anisotropic mesh adaptivity technique is implemented in the Chaste physiological simulation library in order to reduce the mesh resolution away from the depolarization front. Adapting the mesh results in a reduction in the number of degrees of freedom of the system to be solved by an order of magnitude during propagation and 2–3 orders of magnitude in the subsequent plateau phase. As a result, a computational speedup by a factor of between 5 and 12 has been obtained with no loss of accuracy, both in a slab-like geometry and for a realistic heart mesh with a spatial resolution of 0.125 mm.
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Journal articleMatthaei SK, Nick HM, Pain C, et al., 2010,
Simulation of Solute Transport Through Fractured Rock: A Higher-Order Accurate Finite-Element Finite-Volume Method Permitting Large Time Steps
, TRANSPORT IN POROUS MEDIA, Vol: 83, Pages: 289-318, ISSN: 0169-3913- Author Web Link
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- Citations: 42
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Journal articleSchulte P, Alegret L, Arenillas I, et al., 2010,
Response - Cretaceous Extinctions
, SCIENCE, Vol: 328, Pages: 975-976, ISSN: 0036-8075- Author Web Link
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- Citations: 9
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Journal articleWells MR, Allison PA, Piggott MD, et al., 2010,
Tidal modeling of an ancient tide-dominated seaway, part 2: the Aptian Lower Greensand seaway of northwest Europe
, Journal of Sedimentary Research, Vol: 80, Pages: 411-439, ISSN: 1527-1404 -
Journal articleWells MR, Allison PA, Piggott MD, et al., 2010,
Tidal modeling of an ancient tide-dominated seaway, part 1: model validation and application to global early Cretaceous (Aptian) tides
, Journal of Sedimentary Research, Vol: 80, Pages: 393-410, ISSN: 1527-1404 -
Journal articleTong M, Neethling SJ, 2010,
The size of films in dry foams
, JOURNAL OF PHYSICS-CONDENSED MATTER, Vol: 22, ISSN: 0953-8984- Author Web Link
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- Citations: 2
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Journal articleSchulte P, Alegret L, Arenillas I, et al., 2010,
The Chicxulub Asteroid Impact and Mass Extinction at the Cretaceous-Paleogene Boundary
, SCIENCE, Vol: 327, Pages: 1214-1218, ISSN: 0036-8075- Author Web Link
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- Citations: 886
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Journal articleCole KE, Waters KE, Parker DJ, et al., 2010,
PEPT combined with high speed digital imaging for particle tracking in dynamic foams
, CHEMICAL ENGINEERING SCIENCE, Vol: 65, Pages: 1887-1890, ISSN: 0009-2509- Author Web Link
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- Citations: 18
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Journal articleBuchan AG, Candy AS, Merton SR, et al., 2010,
The Inner-Element Subgrid Scale Finite Element Method for the Boltzmann Transport Equation
, NUCLEAR SCIENCE AND ENGINEERING, Vol: 164, Pages: 105-121, ISSN: 0029-5639This paper is of particular importance to the nuclear community as it offers a new, efficient and accurate method for resolving the spatial dimensions of the radiation transport (RT) equation. Solving the RT equation can be extremely demanding as its discretisation leads to unusually large and computationally expensive systems. This sub-grid model therefore blends an accurate and stable discontinuous Galerkin method within a computationally efficient continuous framework. It is shown to produce accurate and stable approximations that also capture large solution gradients. This can all be achieved whilst reducing the problem size by up to a factor of 20.
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Journal articleTAGGART S, HAMPSON GJ, JACKSON MD, 2010,
High-resolution stratigraphic architecture and lithological heterogeneity within marginal aeolian reservoir analogues
, Sedimentology, ISSN: 0037-0746 -
Journal articleGuasch L, Warner MR, Stekl I, et al., 2010,
3D elastic wavefield inversion in the time domain
, 72nd European Association of Geoscientists and Engineers Conference and Exhibition 2010: A New Spring for Geoscience. Incorporating SPE EUROPEC 2010, Vol: 1, Pages: 26-30We have developed a 3D tomographic wavefield inversion code that solves the fully elastic wave equation in the time domain using finite differences. We show results of applying this elastic code to different synthetic 3D problems. © 2010, European Association of Geoscientists and Engineers.
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Journal articleShah NK, Warner MR, Guasch L, et al., 2010,
A strategy for waveform inversion without an accurate starting model
, 72nd European Association of Geoscientists and Engineers Conference and Exhibition 2010: A New Spring for Geoscience. Incorporating SPE EUROPEC 2010, Vol: 7, Pages: 4846-4850A key limitation of waveform inversion as currently implemented is the need for a starting model of high accuracy or field data with low frequencies. Here we present a new approach - staged waveform inversion - designed to mitigate this need and thereby permit the application of waveform inversion to a much wider range of datasets. © 2010, European Association of Geoscientists and Engineers.
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Journal articleWeller H, Ringler T, Piggott M, et al., 2010,
CHALLENGES FACING ADAPTIVE MESH MODELING OF THE ATMOSPHERE AND OCEAN
, BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY, Vol: 91, Pages: 105-+, ISSN: 0003-0007- Author Web Link
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- Citations: 21
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Journal articleMitchell AJ, Allison PA, Piggott MD, et al., 2010,
Numerical modelling of tsunami propagation with implications for sedimentation in ancient epicontinental seas: the Lower Jurassic Laurasian Seaway
, Journal of Sedimentary Geology, Vol: 228, Pages: 81-97, ISSN: 0037-0738 -
Journal articleGarcia X, Pavlidis D, Gorman GJ, et al., 2010,
A two-phase adaptive finite element method for solid–fluidcoupling in complex geometries
, International Journal for Numerical Methods in FluidsIn this paper we present a method to solve the Navier–Stokes equations in complex geometries, suchas porous sands, using a finite-element solver but without the complexity of meshing the porous space.The method is based on treating the solid boundaries as a second fluid and solving a set of equationssimilar to those used for multi-fluid flow. When combined with anisotropic mesh adaptivity, it is possibleto resolve complex geometries starting with an arbitrary coarse mesh. The approach is validated bycomparing simulation results with available data in three test cases. In the first we simulate the flow pasta cylinder. The second test case compares the pressure drop in flow through random packs of sphereswith the Ergun equation. In the last case simulation results are compared with experimental data on theflow past a simplified vehicle model (Ahmed body) at high Reynolds number using large-eddy simulation(LES). Results are in good agreement with all three reference models.
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Journal articleMitchell AJ, Ulicny D, Hampson GJ, et al., 2010,
Modelling tidal current-induced bed shear stress and palaeocirculation in an epicontinental seaway: the Bohemian Cretaceous Basin, Central Europe
, Sedimentology, Vol: 57, Pages: 359-388, ISSN: 0037-0746 -
Conference paperGuo X, Gorman G, Ashworth M, et al., 2010,
High Performance Computing Driven Software Development for Next-Generation Modelling of the Worlds Oceans
, Cray Users Group ConferenceThe Imperial College Ocean Model (ICOM) is an open-source next generation ocean model build upon finite element methods and anisotropic unstructured adaptive meshing. Since 2009, a project has been funded by EPSRC to optimise the ICOM for the UK national high-end computing resource, HECToR (Cray XT4). Extensive use of profiling tools such as CrayPAT and Vampir, has been made in order to understand performance issues of the code on the Cray XT4. Of particular interest is the scalability of the sparse linear solvers and the algebraic multigrid preconditioners required to solve the system of equations.
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Journal articleMiles BE, Pain CC, Gomes JLMA, et al., 2010,
Simulation of a gas-cooled fluidized bed nuclear reactor. Part I: Mixed oxide fuels
, Annals of Nuclear Energy, Vol: 37, Pages: 999-1013 -
Journal articlePavlidis D, Gorman GJ, Gomes JLMA, et al., 2010,
Synthetic-Eddy Method for Urban Atmospheric Flow Modelling
, Boundary-Layer Meteorology, Vol: 136, Pages: 285-299 -
Conference paperPavlidis D, Gomes JLMA, Gorman GJ, et al., 2010,
Novel Mesh Adaptive LES Simulations for Multi-Scale Atmospheric Flows: Application to the Urban Environment
, 30th NATO/SPS International Technical Meeting on Air Pollution Modeling and Its Applications, Publisher: SPRINGER, Pages: 63-+, ISSN: 1871-465X- Author Web Link
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- Citations: 1
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Journal articleFarrell PE, Piggott MD, Gorman GJ, et al., 2010,
Automated continuous verification and validation for numerical simulation
, Geoscientific Model Development Discussions, Vol: 3, Pages: 1587-1623 -
Conference paperSouthern J, Gorman GJ, Piggott MD, et al., 2010,
Anisotropic mesh adaptivity for cardiac electrophysiology
, Pages: 929-938-929-938 -
Journal articleKramer SC, Cotter CJ, Pain CC, 2010,
Solving the Poisson equation on small aspect ratio domains using unstructured meshes
, OCEAN MODELLING, Vol: 35, Pages: 253-263, ISSN: 1463-5003- Author Web Link
- Open Access Link
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- Citations: 13
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Journal articleVinogradov J, Jaafar MZ, Jackson MD, 2010,
Measurement of Streaming Potential Coupling Coefficient in Sandstones Saturated with Natural and Artificial Brines at High Salinity
, Journal of Geophysical Research -
Journal articleGlover PWJ, Jackson MD, 2010,
Borehole electrokinetics
, The Leading Edge, Vol: 29, Pages: 724-728 -
Journal articleMiles BE, Pain CC, Gomes JLMA, 2010,
Simulation of a gas-cooled fluidized bed nuclear reactor Part II: Stability of a fluidized bed reactor with mixed oxide fuels
, Annals of Nuclear Energy, Vol: 37, Pages: 1014-1025 -
Journal articleLeinov E, Vinogradov J, Jackson MD, 2010,
Salinity Dependence of the Thermoelectric Coupling Coefficient in Brine-Saturated Sandstones
, Geophysical Research Letters -
Conference paperLatham J-P, Xiang J, 2010,
Fold development in compressed multi-layers modelled with FEMDEM
, 5th International Conference on Discrete Element Methods -
Conference paperXiang J, Latham J-P, 2010,
Implementation of tangential force in 3D Discrete Element and Combined Finite-Discrete Element Methods.
, 5th International Conference on Discrete Element Methods -
Conference paperLatham J-P, Xiang J, Harrison JP, et al., 2010,
Development of Virtual Geoscience Simulation Tools, VGeST using the combined finite discrete element method, FEMDEM
, 5th International Conference on Discrete Element Methods -
Journal articleLamb AR, Gorman GJ, Gosselin OR, et al., 2010,
Finite element coupled deformation and fluid flow in fractured porous media
, 72nd European Association of Geoscientists and Engineers Conference and Exhibition 2010: A New Spring for Geoscience. Incorporating SPE EUROPEC 2010, Vol: 2, Pages: 1146-1161We present a finite element scheme which combines the dual permeability method (DPM) and the extended finite element method (XFEM) to simulate coupled deformation and fluid flow in fractured porous media. The scheme incorporates spatial variability in fracture properties without requiring the fracture to be discretized or aligned with the computational mesh. DPM is used to describe the fluid flow interaction between the porous matrix and fractures, whilst XFEM is used to address the discontinuous displacement field within elements which intersect fractures. The method is strongly coupled and solves the stress and flow equations simultaneously for each time increment. DPM-XFEM uses the level set method (LSM) to define existing fractures and eliminates the need for their explicit discretization during simulation. The method performs well on coarse structured grids and does not require complex, difficult to generate meshes to conduct simulations. Comparison between the proposed method and the discrete fracture method (DFM) shows its ability to adequately determine the displacement and fluid pore pressure distribution within a fractured domain. © 2010, European Association of Geoscientists and Engineers.
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Journal articleAristodemou E, Bentham T, Pain C, et al., 2009,
A comparison of mesh-adaptive LES with wind tunnel data for flow past buildings: Mean flows and velocity fluctuations
, ATMOSPHERIC ENVIRONMENT, Vol: 43, Pages: 6238-6253, ISSN: 1352-2310- Author Web Link
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- Citations: 28
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