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  • Journal article
    Morgan JV, Warner MR, Collins GS, Grieve RAF, Christeson GL, Gulick SPS, Barton PJet al., 2011,

    Full waveform tomographic images of the peak ring at the Chicxulub impact crater

    , Journal of Geophysical Research, Vol: 116

    Peak 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.

  • Journal article
    Farrell PE, Piggott MD, Gorman GJ, Ham DA, Wilson CR, Bond TMet al., 2011,

    Automated continuous verification for numerical simulation

    , Geoscientific Model Development, Vol: 4, Pages: 435-449
  • Journal article
    Mitchell AJ, Allison PA, Gorman GJ, Piggott MD, Pain CCet al., 2011,

    Tidal circulation in an ancient epicontinental sea: The Early Jurassic Laurasian Seaway

    , Geology, Vol: 39, Pages: 207-210, ISSN: 0091-7613
  • Conference paper
    Piotrowski M, Sloan TM, Mewsissen M, Forster T, Mitchell L, Petrou S, Dobrezelecki B, Ghazal P, Trew A, Hill Jet al., 2011,

    Optimisation and parallelisation of the partitioning around medoids function in R

    , Pages: 707-713
  • Journal article
    Maddison JR, Marshall DP, Pain CC, Piggott MDet 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
  • Journal article
    Chen 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
  • Book
    Allison 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 article
    Wuennemann 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
  • Software
    Pain C, Allison P, Aristodemou E, Bond T, Bercia GT, Bricheno L, Buchan A, Candy A, Clay G, Collins G, Cotter C, Creech A, Davies R, Dunstall J, Du J, Eaton M, Farrell P, Funke S, Ham D, Hill J, Garcia-Sagrado A, Gomes J, Gorman G, Harrison D, Jacobs C, Jiang S, Kramer S, Liu H, Lutsko N, Maddison J, Martin B, Miles B, Milthaler F, Mindel J, Mitchell A, Nelson R, Pavlidis D, Perpeet R, Piggott M, Plociniczak H, Power P, Sallito M, Saunders J, Shahdatullah S, Tollit B, Wang H, Wells M, Whitworth M, Wilson C, Umpleby Aet al., 2010,

    Fluidity

    , London, Publisher: Applied Modelling and Computation Group (AMCG), Imperial College London
  • Journal article
    Cole KE, Waters KE, Fan X, Neethling SJ, Cilliers JJet 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
  • Journal article
    Morris 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
  • Book chapter
    Pavlidis D, Aristodemou E, Gomes JLMA, Pain CC, ApSimon Het 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: 9789048136513

    This book is of interest to scientists and engineers both at an early level in their career as well as at more senior levels.

  • Journal article
    Munday 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
  • Journal article
    Jackson 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
  • Conference paper
    Davison TM, Collins GS, Ciesla F, O'Brien DPet al., 2010,

    Cumulative impact heating of planetesimals

    , 73rd Annual Meeting of the Meteoritical-Society, Publisher: Wiley-Blackwell, Pages: A43-A43, ISSN: 1086-9379
  • Journal article
    Davison TM, Collins GS, Ciesla FJ, 2010,

    Numerical modelling of heating in porous planetesimal collisions

    , ICARUS, Vol: 208, Pages: 468-481, ISSN: 0019-1035
  • Conference paper
    Pasek MA, Collins GS, Carter EA, Melosh HJ, Atlas Zet 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 paper
    Lamb A, Gorman G, Gosselin O, Onaisi Aet al., 2010,

    Coupled Deformation and Fluid Flow in Fractured Porous Media using Dual Permeability and Explicitly Defined Fracture Geometry

    , 72nd EAGE Conference & Exhibition

    We 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.

  • Journal article
    Southern J, Gorman GJ, Piggott MD, Farrell PE, Bernabeu MO, Pitt-Francis Jet al., 2010,

    Simulating cardiac electrophysiology using anisotropic mesh adaptivity

    , Journal of Computational Science, Vol: 1, Pages: 82-88

    The 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.

  • Journal article
    Matthaei SK, Nick HM, Pain C, Neuweiler Iet 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
  • Journal article
    Schulte P, Alegret L, Arenillas I, Arz JA, Barton PJ, Bown PR, Bralower TJ, Christeson GL, Claeys P, Cockell CS, Collins GS, Deutsch A, Goldin TJ, Goto K, Grajales-Nishimura JM, Grieve RAF, Gulick SPS, Johnson KR, Kiessling W, Koeberl C, Kring DA, Macleod KG, Matsui T, Melosh J, Montanari A, Morgan JV, Neal CR, Norris RD, Pierazzo E, Ravizza G, Rebolledo-Vieyra M, Reimold WU, Robin E, Salge T, Speijer RP, Sweet AR, Urrutia-Fucugauchi J, Vajda V, Whalen MT, Willumsen PSet al., 2010,

    Response - Cretaceous Extinctions

    , SCIENCE, Vol: 328, Pages: 975-976, ISSN: 0036-8075
  • Journal article
    Wells MR, Allison PA, Piggott MD, Hampson GJ, Pain CC, Gorman GJet 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 article
    Wells MR, Allison PA, Piggott MD, Hampson GJ, Pain CC, Gorman GJet 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 article
    Tong M, Neethling SJ, 2010,

    The size of films in dry foams

    , JOURNAL OF PHYSICS-CONDENSED MATTER, Vol: 22, ISSN: 0953-8984
  • Journal article
    Schulte P, Alegret L, Arenillas I, Arz JA, Barton PJ, Bown PR, Bralower TJ, Christeson GL, Claeys P, Cockell CS, Collins GS, Deutsch A, Goldin TJ, Goto K, Grajales-Nishimura JM, Grieve RAF, Gulick SPS, Johnson KR, Kiessling W, Koeberl C, Kring DA, MacLeod KG, Matsui T, Melosh J, Montanari A, Morgan JV, Neal CR, Nichols DJ, Norris RD, Pierazzo E, Ravizza G, Rebolledo-Vieyra M, Reimold WU, Robin E, Salge T, Speijer RP, Sweet AR, Urrutia-Fucugauchi J, Vajda V, Whalen MT, Willumsen PSet al., 2010,

    The Chicxulub Asteroid Impact and Mass Extinction at the Cretaceous-Paleogene Boundary

    , SCIENCE, Vol: 327, Pages: 1214-1218, ISSN: 0036-8075
  • Journal article
    Cole KE, Waters KE, Parker DJ, Neethling SJ, Cilliers JJet 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
  • Journal article
    Buchan AG, Candy AS, Merton SR, Pain CC, Hadi JI, Eaton MD, Goddard AJHet 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: 0029-5639

    This 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.

  • Journal article
    TAGGART S, HAMPSON GJ, JACKSON MD, 2010,

    High-resolution stratigraphic architecture and lithological heterogeneity within marginal aeolian reservoir analogues

    , Sedimentology, ISSN: 0037-0746
  • Journal article
    Guasch L, Warner MR, Stekl I, Umpleby APet 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: 26-30

    We 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.

  • Journal article
    Shah NK, Warner MR, Guasch L, Stekl I, Umpleby APet 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: 4846-4850

    A 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.

  • Journal article
    Weller H, Ringler T, Piggott M, Wood Net 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
  • Journal article
    Mitchell AJ, Allison PA, Piggott MD, Gorman GJ, Pain CC, Hampson GJet 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 article
    Garcia X, Pavlidis D, Gorman GJ, Gomes JLMA, Piggott MD, Aristodemou E, Mindel J, Latham JP, Pain CC, ApSimon Het al., 2010,

    A two-phase adaptive finite element method for solid–fluidcoupling in complex geometries

    , International Journal for Numerical Methods in Fluids

    In 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.

  • Journal article
    Mitchell AJ, Ulicny D, Hampson GJ, Allison PA, Gorman GJ, Piggott MD, Wells MR, Pain CCet 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 paper
    Guo X, Gorman G, Ashworth M, Kramer S, Piggott M, Sunderland Set al., 2010,

    High Performance Computing Driven Software Development for Next-Generation Modelling of the Worlds Oceans

    , Cray Users Group Conference

    The 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.

  • Journal article
    Miles BE, Pain CC, Gomes JLMA, Tollit Bet 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 article
    Pavlidis D, Gorman GJ, Gomes JLMA, Pain CC, ApSimon Het al., 2010,

    Synthetic-Eddy Method for Urban Atmospheric Flow Modelling

    , Boundary-Layer Meteorology, Vol: 136, Pages: 285-299
  • Conference paper
    Pavlidis D, Gomes JLMA, Gorman GJ, Aristodemou E, Pain CC, ApSimon H, Robins AGet 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
  • Journal article
    Farrell PE, Piggott MD, Gorman GJ, Ham DA, Wilson CRet al., 2010,

    Automated continuous verification and validation for numerical simulation

    , Geoscientific Model Development Discussions, Vol: 3, Pages: 1587-1623
  • Conference paper
    Southern J, Gorman GJ, Piggott MD, Farrell PE, Bernabeu MO, Pitt-Francis Jet al., 2010,

    Anisotropic mesh adaptivity for cardiac electrophysiology

    , Pages: 929-938-929-938
  • Journal article
    Kramer 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
  • Journal article
    Vinogradov 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 article
    Glover PWJ, Jackson MD, 2010,

    Borehole electrokinetics

    , The Leading Edge, Vol: 29, Pages: 724-728
  • Journal article
    Miles 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 article
    Leinov E, Vinogradov J, Jackson MD, 2010,

    Salinity Dependence of the Thermoelectric Coupling Coefficient in Brine-Saturated Sandstones

    , Geophysical Research Letters
  • Conference paper
    Latham J-P, Xiang J, 2010,

    Fold development in compressed multi-layers modelled with FEMDEM

    , 5th International Conference on Discrete Element Methods
  • Conference paper
    Xiang 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 paper
    Latham J-P, Xiang J, Harrison JP, Munjiza Aet 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 article
    Lamb AR, Gorman GJ, Gosselin OR, Onaisi Aet 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: 1146-1161

    We 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.

  • Journal article
    Aristodemou E, Bentham T, Pain C, Colvile R, Robins A, ApSimon Het 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

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