Imperial College London

PETER A. ALLISON

Faculty of EngineeringDepartment of Earth Science & Engineering

Professor of Earth Science
 
 
 
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Contact

 

+44 (0)20 7594 6479p.a.allison Website

 
 
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Location

 

4.84Royal School of MinesSouth Kensington Campus

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Summary

 

Publications

Publication Type
Year
to

98 results found

Amir Hassan MH, Johnson HD, Allison PA, Abdullah WHet al., 2017, Sedimentology and stratigraphic architecture of a Miocene retrogradational, tide-dominated delta system: Balingian Province, offshore Sarawak, Malaysia, Geological Society, London, Special Publications, Vol: 444, Pages: 215-250, ISSN: 0305-8719

JOURNAL ARTICLE

Collins DS, Avdis A, Allison PA, Johnson HD, Hill J, Piggott MD, Hassan MHA, Damit ARet al., 2017, Tidal dynamics and mangrove carbon sequestration during the Oligo-Miocene in the South China Sea, NATURE COMMUNICATIONS, Vol: 8, ISSN: 2041-1723

JOURNAL ARTICLE

Collins DS, Johnson HD, Allison PA, Guilpain P, Damit ARet al., 2017, Coupled 'storm-flood' depositional model: Application to the Miocene-Modern Baram Delta Province, north-west Borneo, SEDIMENTOLOGY, Vol: 64, Pages: 1203-1235, ISSN: 0037-0746

JOURNAL ARTICLE

Parkinson SD, Funke SW, Hill J, Piggott MD, Allison PAet al., 2017, Application of the adjoint approach to optimise the initial conditions of a turbidity current with the AdjointTurbidity 1.0 model, GEOSCIENTIFIC MODEL DEVELOPMENT, Vol: 10, Pages: 1051-1068, ISSN: 1991-959X

JOURNAL ARTICLE

Jacobs CT, Goldin TJ, Collins GS, Piggott MD, Kramer SC, Melosh HJ, Wilson CRG, Allison PAet al., 2015, An improved quantitative measure of the tendency for volcanic ash plumes to form in water: implications for the deposition of marine ash beds, JOURNAL OF VOLCANOLOGY AND GEOTHERMAL RESEARCH, Vol: 290, Pages: 114-124, ISSN: 0377-0273

JOURNAL ARTICLE

Jordan N, Allison PA, Hill J, Sutton MDet al., 2015, Not all aragonitic molluscs are missing: taphonomy and significance of a unique shelly lagerstatte from the Jurassic of SW Britain, LETHAIA, Vol: 48, Pages: 540-548, ISSN: 0024-1164

JOURNAL ARTICLE

Martin-Short R, Hill J, Kramer SC, Avdis A, Allison PA, Piggott MDet al., 2015, .Tidal resource extraction in the Pentland Firth, UK: Potential impacts on flow regime and sediment transport in the Inner Sound of Stroma, RENEWABLE ENERGY, Vol: 76, Pages: 596-607, ISSN: 0960-1481

JOURNAL ARTICLE

Hiester HR, Piggott MD, Farrell PE, Allison PAet al., 2014, Assessment of spurious mixing in adaptive mesh simulations of the two-dimensional lock-exchange, OCEAN MODELLING, Vol: 73, Pages: 30-44, ISSN: 1463-5003

JOURNAL ARTICLE

Parkinson SD, Hill J, Piggott MD, Allison PAet al., 2014, Direct numerical simulations of particle-laden density currents with adaptive, discontinuous finite elements, GEOSCIENTIFIC MODEL DEVELOPMENT, Vol: 7, Pages: 1945-1960, ISSN: 1991-959X

JOURNAL ARTICLE

Hassan MHA, Johnson HD, Allison PA, Abdullah WHet al., 2013, Sedimentology and stratigraphic development of the upper Nyalau Formation (Early Miocene), Sarawak, Malaysia: A mixed wave- and tide-influenced coastal system, JOURNAL OF ASIAN EARTH SCIENCES, Vol: 76, Pages: 301-311, ISSN: 1367-9120

JOURNAL ARTICLE

Jordan N, Allison PA, Hill JH, Sutton MDet al., 2012, Carbonates, ammonites and the fate of aragonite: a new perspective from the Lower Jurassic of Lyme Regis, British Sedimentological Research Group Annual Meeting

The Lower Jurassic Blue Lias Formation at Lyme Regis, Dorset, preserves a diverse assemblage of invertebrate and vertebrate fossils within rhythmic packages of shales, marls and carbonates. One limestone bed in particular, Bed 29, preserves a unique pavement of very large (up to 72 cm) ammonites, initially buried in carbonate mud before diagenetic cementation. The ammonite accumulation is most likely due to sedimentological condensation but the mechanisms for preserving an aragonitic shell long enough for it to be neomorphosed to calcite on the seabed are a challenge for conventional taphonomic models. It has been suggested that early dissolution of aragonite is a major process in offshore deeper ramp settings, resulting in the removal of sediment prior to lithification. We present field-based evidence for a new model of aragonite preservation within a cyclic oxic-anoxic carbonate environment, using ammonite preservation to track the fate of aragonite in different depositional environments. The carbonate sediment provides a short-term geochemical buffer that militates against the dissolution of aragonite sediment and molluscs, allowing neomorphism to calcite under some conditions. The broader implications of this model for the preservation of molluscan shells and reduced sediment dissolution in carbonate environments under variably oxygenated conditions are evaluated.

CONFERENCE PAPER

Allison PA, Bottjer DJ, 2011, Taphonomy: Bias and Process Through Time (Volume 32 in the Topics in Geobiology series), Publisher: Springer, ISBN: 978-90-481-8642-6

BOOK

Allison PA, Bottjer DJ, 2011, Taphonomy: Bias and Process Through Time, Taphonomy: Bias and Process Through Time (Volume 32 in the Topics in Geobiology series), Editors: Allison, Bottjer, Publisher: Springer, Pages: 1-18, ISBN: 978-90-481-8642-6

BOOK CHAPTER

Brett CE, Allison PA, Hendy AJW, 2011, Comparative taphonomy and sedimentology of small-scale mixed carbonate/siliciclastic cycles: Synopsis of Phanerozoic examples, Taphonomy: Bias and Process Through Time (Volume 32 in the Topics in Geobiology series), Editors: Allison, Bottjer, Publisher: Springer, Pages: 107-198, ISBN: 978-90-481-8642-6

BOOK CHAPTER

Fang F, Pain CC, Navon IM, Gorman GJ, Piggott MD, Allison PAet al., 2011, The independent set perturbation adjoint method: A new method of differentiating mesh-based fluids models, INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Vol: 66, Pages: 976-999, ISSN: 0271-2091

JOURNAL ARTICLE

Hiester HR, Piggott MD, Allison PA, 2011, The impact of mesh adaptivity on the gravity current front speed in a two-dimensional lock-exchange, OCEAN MODELLING, Vol: 38, Pages: 1-21, ISSN: 1463-5003

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

JOURNAL ARTICLE

Fang F, Pain CC, Navon IM, Gorman GJ, Piggott MD, Allison PA, Goddard AJHet al., 2010, A POD goal-oriented error measure for mesh optimization, International Journal for Numerical Methods in Fluids, Vol: 63, Pages: 185-206, ISSN: 0271-2091

The approach for designing an error measure to guide an adaptive meshing algorithm proposed in Power et al. (Ocean Modell. 2006; 15:3-38) is extended to use a POD adjoint-based method, thus facilitating efficient primal and adjoint integration in time. The aim is to obtain a new mesh that can adequately resolve all the fields at all time levels, with optimal (w.r.t. the functional) efficiency. The goal-based method solves both the primal and adjoint equations to form the overall error norms, in the form of a metric tensor. The tetrahedral elements are then optimized so that they have unit size in Riemannian space defined with respect to the metric tensor. This is the first attempt to use POD to estimate an anisotropic error measure. The metric tensor field can be used to direct anisotropic mesh adaptivity. The resulting mesh is optimized to efficiently represent the solution fields over a given time period. The calculation of the error measures is carried out in the reduced space. The POD approach facilitates efficient integration backwards in time and yields the sensitivity analysis necessary for the goal-based error estimates. The accuracy of both the primal and adjoint-reduced models is thus optimized (through the use of anisotropic mesh adaptivity). In addition, the functional for optimizing meshes has been designed to be consistent with that for 4D Var data assimilation. Copyright © 2009 John Wiley & Sons, Ltd.

JOURNAL ARTICLE

Fang F, Pain CC, Navon IM, Gorman GJ, Piggott MD, Allison PA, Goddard AJHet al., 2010, A POD goal-oriented error measure for mesh optimization, INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Vol: 63, Pages: 185-206, ISSN: 0271-2091

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, SEDIMENTARY GEOLOGY, Vol: 228, Pages: 81-97, ISSN: 0037-0738

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

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

Brett CE, Allison PA, DeSantis MK, Liddell WD, Kramer Aet al., 2009, Sequence stratigraphy, cyclic facies, and lagerstatten in the Middle Cambrian Wheeler and Marjum Formations, Great Basin, Utah, PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY, Vol: 277, Pages: 9-33, ISSN: 0031-0182

JOURNAL ARTICLE

Fang F, Pain CC, Navon IM, Gorman GJ, Piggott MD, Allison PA, Farrell PE, Goddard AJHet al., 2009, A POD reduced order unstructured mesh ocean modelling method for moderate Reynolds number flows, Ocean Modelling, Vol: 28, Pages: 127-136, ISSN: 1463-5003

Herein a new approach to enhance the accuracy of a novel Proper Orthogonal Decomposition (POD) model applied to moderate Reynolds number flows (of the type typically encountered in ocean models) is presented. This approach develops the POD model of Fang et al. [Fang, F., Pain, C.C., Navon, I.M., Piggott, M.D., Gorman, G.J., Allison, P., Goddard, A.J.H., 2008. Reduced-order modelling of an adaptive mesh ocean model. International Journal for Numerical Methods in Fluids. doi:10.1002/fld.1841] used in conjunction with the Imperial College Ocean Model (ICOM), an adaptive, non-hydrostatic finite element model. Both the velocity and vorticity results of the POD reduced order model (ROM) exhibit an overall good agreement with those obtained from the full model. The accuracy of the POD-Galerkin model with the use of adaptive meshes is first evaluated using the Munk gyre flow test case with Reynolds numbers ranging between 400 and 2000. POD models using the L 2 norm become oscillatory when the Reynolds number exceeds Re = 400. This is because the low-order truncation of the POD basis inhibits generally all the transfers between the large and the small (unresolved) scales of the fluid flow. Accuracy is improved by using the H 1 POD projector in preference to the L 2 POD projector. The POD bases are constructed by incorporating gradients as well as function values in the H 1 Sobolev norm. The accuracy of numerical results is further enhanced by increasing the number of snapshots and POD bases. Error estimation was used to assess the effect of truncation (involved in the POD-Galerkin approach) when adaptive meshes are used in conjunction with POD/ROM. The RMSE of velocity results between the full model and POD-Galerkin model is reduced by as much as 50% by using the H 1 norm and increasing the number of snapshots and POD bases. © 2008 Elsevier Ltd.

JOURNAL ARTICLE

Fang F, Pain CC, Navon IM, Gorman GJ, Piggott MD, Allison PA, Farrell PE, Goddard AJHet al., 2009, A POD reduced order unstructured mesh ocean modelling method for moderate Reynolds number flows, OCEAN MODELLING, Vol: 28, Pages: 127-136, ISSN: 1463-5003

JOURNAL ARTICLE

Fang F, Pain CC, Navon IM, Piggott MD, Gorman GJ, Allison PA, Goddard AJHet al., 2009, Reduced-order modelling of an adaptive mesh ocean model, INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Vol: 59, Pages: 827-851, ISSN: 0271-2091

JOURNAL ARTICLE

Fang F, Pain CC, Navon IM, Piggott MD, Gorman GJ, Farrell PE, Allison PA, Goddard AJHet al., 2009, A POD reduced-order 4D-Var adaptive mesh ocean modelling approach, INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Vol: 60, Pages: 709-732, ISSN: 0271-2091

JOURNAL ARTICLE

Halgedahl SL, Jarrard RD, Brett CE, Allison PAet al., 2009, Geophysical and geological signatures of relative sea level change in the upper Wheeler Formation, Drum Mountains, West-Central Utah: A perspective into exceptional preservation of fossils, PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY, Vol: 277, Pages: 34-56, ISSN: 0031-0182

JOURNAL ARTICLE

Allison PA, Hesselbo SP, Brett CE, 2008, Methane seeps on an Early Jurassic dysoxic seafloor, PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY, Vol: 270, Pages: 230-238, ISSN: 0031-0182

JOURNAL ARTICLE

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