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  • JOURNAL ARTICLE
    Han B, Zdravkovic L, Kontoe S, 2016,

    Numerical and analytical investigation of compressional wave propagation in saturated soils

    , COMPUTERS AND GEOTECHNICS, Vol: 75, Pages: 93-102, ISSN: 0266-352X
  • JOURNAL ARTICLE
    Jackson CAL, Lewis MM, 2016,

    Structural style and evolution of a salt-influenced rift basin margin: the impact of variations in salt composition and the role of polyphase extension

    , Basin Research, Vol: 28, Pages: 81-102

    Because salt can decouple sub- and supra-salt deformation, the structural style and evolution of salt-influenced rifts differs from those developed in megoscopically homogenous and brittle crust. Our understanding of the structural style and evolution of salt-influenced rifts comes from scaled physical models, or subsurface-based studies that have utilised moderate-quality 2D seismic reflection data. Relatively few studies have used high-quality 3D seismic reflection data, constrained by borehole data, to explicitly focus on the role that along-strike displacement variations on sub-salt fault systems, or changes in salt composition and thickness, play in controlling the four-dimensional evolution of supra-salt structural styles. In this study, we use 3D seismic reflection and borehole data from the Sele High Fault System (SHFS), offshore Norway to determine how rift-related relief controlled the thickness and lithology of an Upper Permian salt-bearing layer (Zechstein Supergroup), and how the associated variations in the mechanical properties of this unit influenced the degree of coupling between sub- and supra-salt deformation during subsequent extension. Seismic and borehole data indicate that the Zechstein Supergroup is thin, carbonate-dominated and immobile at the footwall apex, but thick, halite-dominated and relatively mobile in high accommodation areas, such as near the lateral fault tips and in the immediate hangingwall of the fault system. We infer that these variations reflect bathymetric changes related to either syn-depositional (i.e. Late Permian) growth of the SHFS or underfilled, fault scarp-related relief inherited from a preceding (i.e. Early Permian) rift phase. After a period of tectonic quiescence in the Early Triassic, regional extension during the Late Triassic triggered halokinesis and growth of a fault-parallel salt wall, which was followed by mild extension in the Jurassic and forced folding of Triassic overburden above the fault systems upp

  • JOURNAL ARTICLE
    Jacobs CT, Piggott MD, Kramer SC, Funke SWet al., 2016,

    On the validity of tidal turbine array configurations obtained from steady-state adjoint optimisation

    , ECCOMAS Congress 2016 - Proceedings of the 7th European Congress on Computational Methods in Applied Sciences and Engineering, Vol: 4, Pages: 8247-8261

    Extracting the optimal amount of power from an array of tidal turbines requires an intricate understanding of tidal dynamics and the effects of turbine placement on the local and regional scale flow. Numerical models have contributed significantly towards this understanding, and more recently, adjoint-based modelling has been employed to optimise the positioning of the turbines in an array in an automated way and improve on simple man-made configurations (e.g. structured grids of turbines) [1]. Adjoint-based optimisation of high-resolution and ideally 3D transient models is generally a very computationally expensive problem. Multiple approaches are therefore used in practice to obtain feasible runtimes: using high viscosity values to obtain a steady-state solution, or a sequence of steady-state solutions for "time-varying" setups; limiting the number of adjoint computations; or reformulating the problem to allow for coarser mesh resolution to make it feasible for resources assessment (e.g. [2] , [3]). However, such compromises may affect the reliability of the modelled turbines, their wakes and interactions, and thus bring into question the validity of the computed optimal turbine positions. This work considers a suite of idealised simulations of flow past tidal turbine arrays in a two-dimensional channel. It compares four regular array configurations, detailed by Divett et al. [4] , with the configuration found through adjoint optimisation in a steady-state, high-viscosity setup. The optimised configuration produces considerably more power than the other configurations (approximately 40% more than the best man-made configuration). The same configurations are then used to produce a suite of transient simulations that do not use constant high-viscosity, and instead use large eddy simulation (LES) to parameterise the resulting turbulent structures. All simulations are performed using OpenTidalFarm [1]. It is shown that the 'low background viscosity'/LES simu

  • JOURNAL ARTICLE
    Johnson BC, Blair DM, Collins GS, Melosh HJ, Freed AM, Taylor GJ, Head JW, Wieczorek MA, Andrews-Hanna JC, Nimmo F, Keane JT, Miljkovic K, Soderblom JM, Zuber MTet al., 2016,

    Formation of the Orientale lunar multiring basin

    , SCIENCE, Vol: 354, Pages: 441-444, ISSN: 0036-8075
  • JOURNAL ARTICLE
    Johnson BC, Collins GS, Minton DA, Bowling TJ, Simonson BM, Zuber MTet al., 2016,

    Spherule layers, crater scaling laws, and the population of ancient terrestrial impactors

    , ICARUS, Vol: 271, Pages: 350-359, ISSN: 0019-1035
  • JOURNAL ARTICLE
    Kent E, Boulton SJ, Stewart IS, Whittaker AC, Alcicek MCet al., 2016,

    Geomorphic and geological constraints on the active normal faulting of the Gediz (Alasehir) Graben, Western Turkey

    , JOURNAL OF THE GEOLOGICAL SOCIETY, Vol: 173, Pages: 666-678, ISSN: 0016-7649
  • JOURNAL ARTICLE
    Kramer SC, Piggott MD, 2016,

    A correction to the enhanced bottom drag parameterisation of tidal turbines

    , Renewable Energy, Vol: 92, Pages: 385-396, ISSN: 1879-0682

    Hydrodynamic modelling is an important tool for the development of tidalstream energy projects. Many hydrodynamic models incorporate the effect oftidal turbines through an enhanced bottom drag. In this paper we show thatalthough for coarse grid resolutions (kilometre scale) the resulting force exertedon the flow agrees well with the theoretical value, the force starts decreasingwith decreasing grid sizes when these become smaller than the length scale ofthe wake recovery. This is because the assumption that the upstream velocitycan be approximated by the local model velocity, is no longer valid. Using linearmomentum actuator disc theory however, we derive a relationship between thesetwo velocities and formulate a correction to the enhanced bottom drag formulationthat consistently applies a force that remains close to the theoretical value,for all grid sizes down to the turbine scale. In addition, a better understandingof the relation between the model, upstream, and actual turbine velocity, aspredicted by actuator disc theory, leads to an improved estimate of the usefullyextractable energy. We show how the corrections can be applied (demonstratedhere for the models MIKE 21 and Fluidity) by a simple modification of the dragcoefficient.

  • JOURNAL ARTICLE
    Kring DA, Kramer GY, Collins GS, Potter RWK, Chandnani Met al., 2016,

    Peak-ring structure and kinematics from a multi-disciplinary study of the Schrodinger impact basin

    , NATURE COMMUNICATIONS, Vol: 7, ISSN: 2041-1723
  • JOURNAL ARTICLE
    Maes J, Muggeridge AH, Jackson MD, Quintard M, Lapene Aet al., 2016,

    Modelling in-situ upgrading of heavy oil using operator splitting method

    , COMPUTATIONAL GEOSCIENCES, Vol: 20, Pages: 581-594, ISSN: 1420-0597
  • JOURNAL ARTICLE
    Magee C, Muirhead JD, Karvelas A, Holford SP, Jackson CA-L, Bastow ID, Schofield N, Stevenson CTE, McLean C, McCarthy W, Shtukert Oet al., 2016,

    Lateral magma flow in mafic sill complexes

    , Geosphere, Vol: 12, Pages: 809-841, ISSN: 1553-040X

    The structure of upper crustal magma plumbing systems controls the distribution of volcanism and influences tectonic processes. However, delineating the structure and volume of plumbing systems is difficult because (1) active intrusion networks cannot be directly accessed; (2) field outcrops are commonly limited; and (3) geophysical data imaging the subsurface are restricted in areal extent and resolution. This has led to models involving the vertical transfer of magma via dikes, extending from a melt source to overlying reservoirs and eruption sites, being favored in the volcanic literature. However, while there is a wealth of evidence to support the occurrence of dike-dominated systems, we synthesize field- and seismic reflection–based observations and highlight that extensive lateral magma transport (as much as 4100 km) may occur within mafic sill complexes. Most of these mafic sill complexes occur in sedimentary basins (e.g., the Karoo Basin, South Africa), although some intrude crystalline continental crust (e.g., the Yilgarn craton, Australia), and consist of interconnected sills and inclined sheets. Sill complex emplacement is largely controlled by host-rock lithology and structure and the state of stress. We argue that plumbing systems need not be dominated by dikes and that magma can be transported within widespread sill complexes, promoting the development of volcanoes that do not overlie the melt source. However, the extent to which active volcanic systems and rifted margins are underlain by sill complexes remains poorly constrained, despite important implications for elucidating magmatic processes, melt volumes, and melt sources.

  • JOURNAL ARTICLE
    Magee C, O'Driscoll B, Petronis MS, Stevenson CTEet al., 2016,

    Three-dimensional magma flow dynamics within subvolcanic sheet intrusions

    , GEOSPHERE, Vol: 12, Pages: 842-866, ISSN: 1553-040X
  • JOURNAL ARTICLE
    Maguire R, Ritsema J, van Keken PE, Fichtner A, Goes Set al., 2016,

    P- and S-wave delays caused by thermal plumes

    , GEOPHYSICAL JOURNAL INTERNATIONAL, Vol: 206, Pages: 1169-1178, ISSN: 0956-540X
  • JOURNAL ARTICLE
    Mannie AS, Jackson CA-L, Hampson GJ, Fraser AJet al., 2016,

    Tectonic controls on the spatial distribution and stratigraphic architecture of a net-transgressive shallow-marine synrift succession in a salt-influenced rift basin: Middle to Upper Jurassic, Norwegian Central North Sea

    , JOURNAL OF THE GEOLOGICAL SOCIETY, Vol: 173, Pages: 901-915, ISSN: 0016-7649
  • JOURNAL ARTICLE
    Massart BYG, Jackson MD, Hampson GJ, Johnson HDet al., 2016,

    Effective flow properties of heterolithic, cross-bedded tidal sandstones: Part 2. Flow simulation

    , AAPG BULLETIN, Vol: 100, Pages: 723-742, ISSN: 0149-1423
  • JOURNAL ARTICLE
    Massart BYG, Jackson MD, Hampson GL, Johnson HD, Legler B, Jackson CA-Let al., 2016,

    Effective flow properties of heterolithic, cross-bedded tidal sandstones: Part I. Surface-based modeling

    , AAPG BULLETIN, Vol: 100, Pages: 697-721, ISSN: 0149-1423
  • JOURNAL ARTICLE
    McPhillips D, Hoke GD, Liu-Zeng J, Bierman PR, Rood DH, Niedermann Set al., 2016,

    Dating the incision of the Yangtze River gorge at the First Bend using three-nuclide burial ages

    , GEOPHYSICAL RESEARCH LETTERS, Vol: 43, Pages: 101-110, ISSN: 0094-8276
  • JOURNAL ARTICLE
    Miljkovic K, Collins GS, Wieczorek MA, Johnson BC, Soderblom JM, Neumann GA, Zuber MTet al., 2016,

    Subsurface morphology and scaling of lunar impact basins

    , JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS, Vol: 121, Pages: 1695-1712, ISSN: 2169-9097
  • JOURNAL ARTICLE
    Monteux J, Collins GS, Tobie G, Choblet Get al., 2016,

    Consequences of large impacts on Enceladus' core shape

    , ICARUS, Vol: 264, Pages: 300-310, ISSN: 0019-1035
  • JOURNAL ARTICLE
    Morgan JV, Gulick SPS, Bralower T, Chenot E, Christeson G, Claeys P, Cockell CS, Collins GS, Coolen MJL, Ferriere L, Gebhardt C, Goto K, Jones H, Kring DA, Le Ber E, Lofi J, Long X, Lowery C, Mellett C, Ocampo-Torres R, Osinski GR, Perez-Cruz L, Pickersgill A, Poelchau M, Rae A, Rasmussen C, Rebolledo-Vieyra M, Riller U, Sato H, Schmitt DR, Smit J, Tikoo S, Tomioka N, Urrutia-Fucugauchi J, Whalen M, Wittmann A, Yamaguchi KE, Zylberman Wet al., 2016,

    The formation of peak rings in large impact craters

    , SCIENCE, Vol: 354, Pages: 878-882, ISSN: 0036-8075
  • JOURNAL ARTICLE
    Ortiz-Karpf A, Hodgson DM, Jackson CA-L, McCaffrey WDet al., 2016,

    Mass-transport complexes as markers of deep-water fold-and-thrust belt evolution: insights from the southern Magdalena fan, offshore Colombia

    , Basin Research, ISSN: 0950-091X

This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.

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