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  • CONFERENCE PAPER
    Abolghasemi M, Piggott MD, Spinneken J, Vire A, Cotter CJ, Crammond Set al.,

    Simulating tidal turbines with mesh optimisation and RANS turbulence models

    , 2015 European Wave and Tidal Energy Conference
  • JOURNAL ARTICLE
    Avdis A, Jacobs CT, Hill J, Piggott MD, Gorman GJet al.,

    Shoreline and Bathymetry Approximation in Mesh Generation for Tidal Renewable Simulations

    Due to the fractal nature of the domain geometry in geophysical flowsimulations, a completely accurate description of the domain in terms of acomputational mesh is frequently deemed infeasible. Shoreline and bathymetrysimplification methods are used to remove small scale details in the geometry,particularly in areas away from the region of interest. To that end, a novelmethod for shoreline and bathymetry simplification is presented. Existingshoreline simplification methods typically remove points if the resultantgeometry satisfies particular geometric criteria. Bathymetry is usuallysimplified using traditional filtering techniques, that remove unwanted Fouriermodes. Principal Component Analysis (PCA) has been used in other fields toisolate small-scale structures from larger scale coherent features in a robustway, underpinned by a rigorous but simple mathematical framework. Here wepresent a method based on principal component analysis aimed towardssimplification of shorelines and bathymetry. We present the algorithm in detailand show simplified shorelines and bathymetry in the wider region around theNorth Sea. Finally, the methods are used in the context of unstructured meshgeneration aimed at tidal resource assessment simulations in the coastalregions around the UK.

  • JOURNAL ARTICLE
    Collins GS, Lynch E, McAdam R, Davison TMet al.,

    A numerical assessment of simple airblast models of impact airbursts

    , Meteoritics & Planetary Science, ISSN: 1086-9379
  • JOURNAL ARTICLE
    Funke SW, Kramer SC, Piggott MD,

    Design optimisation and resource assessment for tidal-stream renewable energy farms using a new continuous turbine approach

    , Renewable Energy, ISSN: 1879-0682

    This paper presents a new approach for optimising the design of tidal stream turbine farms. In this approach, the turbine farm is represented by a turbine density function that specifies the number of turbines per unit area and an associated continuous locally-enhanced bottom friction field. The farm design question is formulated as a mathematical optimisation problem constrained by the shallow water equations and solved with efficient, gradient-based optimisation methods. The resulting method is accurate, computationally efficient, allows complex installation constraints, and supports different goal quantities such as to maximise power or profit. The outputs of the optimisation are the optimal number of turbines, their location within the farm, the overall farm profit, the farm's power extraction, and the installation cost.We demonstrate the capabilities of the method on a validated numerical model of the Pentland Firth, Scotland. We optimise the design of four tidal farms simultaneously, as well as individually, and study how farms in close proximity may impact upon one another.

  • CONFERENCE PAPER
    Mason PJ, Rosenbaum MS, Moore JM,

    Predicting future landslides using remotely sensed imagery: the Langhe Hills in Piemonte, NW Italy.

    , 8th International Symposium on Landslides

    Existing landslides in the Langhe Hills, NW Italy, have been identified using digital remotelysensed imagery on the basis of their textural and spectral characteristics. Landsat ThematicMapper and multi-temporal SPOT Panchromatic images reveal landslides produced by a stormevent which occurred in 1994, on the basis of key soil properties. High clay content in the soilsand weathered rock profile enhances moisture retention, particularly in hollows and on concaveslopes. Soil moisture assumes the role of a conditioning factor, alongside smectite and ironoxideswhich have been leached from the rocks, and facilitated by groundwater flow throughfractures. Digital images, produced from Landsat TM, representing hydrated mineral (clay), ironoxideand soil moisture content have enabled identification of areas where conditioning factorsare present.

  • JOURNAL ARTICLE
    Nielsen SG, Yogodzinski G, Prytulak J, Plank T, Kay SM, Kay RW, Blusztajn J, Owens JD, Auro M, Kading Tet al.,

    Tracking along-arc sediment inputs to the Aluetian arc using thallium isotopes

    , Geochimica et Cosmochimica Acta, ISSN: 1872-9533
  • JOURNAL ARTICLE
    Nielsen SG, Yogodzinski G, Prytulak J, Plank T, Kay SM, Kay RW, Blusztajn J, Owens JD, Auro M, Kading Tet al.,

    Tracking along-arc sediment inputs to the Aleutian arc using thallium isotopes

    , Geochimica et Cosmochimica Acta, ISSN: 1872-9533

    Sediment transport from the subducted slab to the mantle wedge is an importantprocess in understanding the chemical and physical conditions of arc magma generation. The Aleutian arc offers an excellent opportunity to study sediment transport processes because the subducted sediment flux varies systematically along strike (Kelemen et al., 2003) and many lavas exhibit unambiguous signatures of sediment addition to the sub-arc mantle (Morris et al.,1990). However, the exact sediment contribution to Aleutian lavas and how these sediments are transported from the slab to the surface are still debated. Thallium (Tl) isotope ratios have great potential to distinguish sediment fluxes in subduction zones because pelagic sediments and lowtemperaturealtered oceanic crust are highly enriched in Tl and display heavy and light Tl isotope compositions, respectively, compared with the upper mantle and continental crust. Here, we investigate the Tl isotope composition of lavas covering almost the entire Aleutianarc a well as sediments outboard of both the eastern (DSDP Sites 178 and 183) and central (ODP Hole 886C) portions of the arc. Sediment Tl isotope compositions change systematically from lighter in the Eastern to heavier in the Central Aleutians reflecting a larger proportion of pelagic sediments when distal from the North American continent. Lavas in the Eastern and CentralAleutians mirror this systematic change to heavier Tl isotope compositions to the west, which shows that the subducted sediment composition is directly translated to the arc east of Kanaga Island. Moreover, quantitative mixing models of Tl and Pb, Sr and Nd isotopes reveal that bulk sediment transfer of ~0.6-1.0% by weight in the Eastern Aleutians and ~0.2-0.6% by weight in the Central Aleutians can account for all four isotope systems. Bulk mixing models, however,require that fractionation of trace element ratios like Ce/Pb, Cs/Tl, and Sr/Nd in the Central and Eastern Aleutians occurs after the sediment c

  • JOURNAL ARTICLE
    Nixon CW, McNeill LC, Bull JM, Bell RE, Gawthorpe RL, Henstock TJ, Christodoulou, Ford M, Taylor B, Sakellariou D, Ferentinos G, Papatheodorou G, Leeder M, Collier RELI, Goodliffe A, Sachpazi M, Kranis Het al.,

    Rapid spatio-temporal variations in rift structure during development of the Corinth Rift, central Greece

    , Tectonics, ISSN: 1944-9194
  • JOURNAL ARTICLE
    Ryan L, Magee C, Jackson CA-L,

    The kinematics of normal faults in the Ceduna Sub-Basin, offshore Southern Australia; implications for hydrocarbon trapping in a frontier basin

    , AAPG Bulletin, ISSN: 0149-1423

    The geometry and growth of normal faults is fundamental to the evolution and petroleum prospectivity of sedimentary basins, controlling trap development, source, reservoir and seal rock distribution, and fluid flow. The poorly studied, petroliferous Ceduna Sub-basin located offshore southern Australia contains an ESE-striking, gravity driven fault array, which soles out onto a SW-dipping detachment horizon. Within the sub-basin, structural closures bound by these gravity driven faults represent the main exploration targets. Determining when these faults and associated traps formed relative to petroleum generation and migration and, more specifically, if the faults reactivated, is thus critical to understanding the prospectivity of the Ceduna Sub-basin. In this study, we use a high-quality, time-migrated 2D seismic reflection survey covering the central Ceduna Sub-basin to constrain the geometry and kinematics of the fault array. Fault throw patterns reveal that most nucleated in the Cenomanian. Although some faults display evidence for continuous growth by upper tip propagation throughout the Cenomanian to Maastrichtian, others grew via either dip linkage of isolated segments or fault reactivation. It is apparent that some faults were inactive during the Turonian-Santonian before reactivating and propagating upwards or dip-linking with overlying, newly formed faults. Continuously growing faults primarily occur in the center of the study area, whereas reactivated faults occur proximal to the sediment source and dip-linked faults developed oceanwards. We suggest that this spatial variation fault growth style was primarily controlled by compositional and mechanical heterogeneities in the Tiger and lower Hammerhead supersequences. In addition to providing insights into the petroleum prospectivity of the Ceduna Sub-basin, this study shows how 2D seismic reflection data can be used to probe the kinematics of normal faults.

  • CONFERENCE PAPER
    Singh A, Gupta S, Sinha R, Carter A, Kristina KJ, Mark DF, Buylaert J-P, Mason PJ, Murray AS, Jain M, Paul Det al.,

    Large–scale avulsion of the late Quaternary Sutlej river in the NW Indo–Gangetic foreland basin

    , European Geosciences Union General Assembly 2015

    River avulsions are important processes in the spatial evolution of river systems in tectonically active sedimentary basins as they govern large–scale patterns of sediment routing. However, the pattern and timing of avulsions in large river systems are poorly documented and not well understood. Here we document late Quaternary paleo– river channel changes in the Indo–Gangetic basin of northwest India. Using a combination of satellite remote sensing and detailed sediment coring, we analyse the large–scale planform geometry, and detailed sedimentary andstratigraphic nature of a major fluvial sedimentary deposit in the shallow subsurface. This sediment body records aggradation of multiple fluvial channel fills. Satellite remote sensing analysis indicates the trace of the buried channel complex and demonstrates that it exists in region of the Himalayan foreland where no major rivers are currently present. Thus it records the former drainage pathway of a major river, which has since been diverted. We use optically stimulated luminescence dating techniques to develop an age model for the stratigraphic succession and hence constrain the timing of river channel existence and diversion. Provenance analysis based on U–Pb dating of detrital zircons and detrital mica Ar–Ar ages indicate sediment sources in the Higher Himalayan Crystalline andLesser Himalayan Crystalline Series indicating that this paleo–river channel system formed a major perennial river derived from the main body of the Himalaya. Specifically we are able to fingerprint bedrock sources in thecatchment of the present–day Sutlej river indicating that the paleo–fluvial system represents the former course of the Sutlej river prior to a major nodal avulsion to its present day course. Our results indicate that on geologically relatively short time–scales, we observe dramatic along strike shifts in the location of major Himalayan rivers. Our sediment records

  • CONFERENCE PAPER
    Skiada E, Kontoe S, Stafford P, Potts DMet al.,

    Canyon Depth Effect on Surface Ground Motion

    , 1st International Conference on Natural Hazards & Infrastructure

    Topographic effects are rarely accounted for in seismic design codes, despite their potential to significantly modify surfaceground motions. This paper investigates the influence of a canyon’s slope height on the surface ground motion through aparametric time-domain Finite Element (FE) study. A two-dimensional plane-strain model of an idealised canyon isconsidered for vertically propagating SV waves, using wavelets as input excitation. The model consists of two step-likeslopes with slope height (H), in a homogeneous linear elastic soil layer overlying rigid bedrock. The analysis results showthat the distribution of topographic aggravation at the ground surface varies significantly with normalized canyon depthover the input wavelength (H/λ) and it does not necessarily reach a maximum at a specific H/λ ratio, as has been suggestedin previous studies. The validity of this conclusion is investigated for different depths to bedrock and soil layer properties.

  • JOURNAL ARTICLE
    Schofield N, Holford S, Millett J, Brown D, Jolley D, Passey SR, Muirhead D, Grove C, Magee C, Murray J, Hole M, Jackson CA-L, Stevenson Cet al., 2017,

    Regional magma plumbing and emplacement mechanisms of the Faroe-Shetland Sill Complex: implications for magma transport and petroleum systems within sedimentary basins

    , BASIN RESEARCH, Vol: 29, Pages: 41-63, ISSN: 0950-091X
  • JOURNAL ARTICLE
    Summersgill FC, Kontoe S, Potts DM, 2017,

    On the use of nonlocal regularisation in slope stability problems

    , COMPUTERS AND GEOTECHNICS, Vol: 82, Pages: 187-200, ISSN: 0266-352X
  • JOURNAL ARTICLE
    Abolghasemi MA, Piggott MD, Spinneken J, Vire A, Cotter CJ, Crammond Set al., 2016,

    Simulating tidal turbines with multi-scale mesh optimisation techniques

    , JOURNAL OF FLUIDS AND STRUCTURES, Vol: 66, Pages: 69-90, ISSN: 0889-9746
  • JOURNAL ARTICLE
    Adam A, Buchan AG, Piggott MD, Pain CC, Hill J, Goffin MAet al., 2016,

    Adaptive Haar wavelets for the angular discretisation of spectral wave models

    , JOURNAL OF COMPUTATIONAL PHYSICS, Vol: 305, Pages: 521-538, ISSN: 0021-9991
  • JOURNAL ARTICLE
    Adam A, Pavlidis D, Percival JR, Salinas P, Xie Z, Fang F, Pain CC, Muggeridge AH, Jackson MDet al., 2016,

    Higher-order conservative interpolation between control-volume meshes: Application to advection and multiphase flow problems with dynamic mesh adaptivity

    , JOURNAL OF COMPUTATIONAL PHYSICS, Vol: 321, Pages: 512-531, ISSN: 0021-9991
  • JOURNAL ARTICLE
    Al-Balushi AN, Neumaier M, Fraser AJ, Jackson CA-Let al., 2016,

    The impact of the Messinian salinity crisis on the petroleum system of the Eastern Mediterranean: a critical assessment using 2D petroleum system modelling

    , PETROLEUM GEOSCIENCE, Vol: 22, Pages: 357-379, ISSN: 1354-0793
  • JOURNAL ARTICLE
    Allen H, Jackson CA-L, Fraser AJ, 2016,

    Gravity-driven deformation of a youthful saline giant: the interplay between gliding and spreading in the Messinian basins of the Eastern Mediterranean

    , PETROLEUM GEOSCIENCE, Vol: 22, Pages: 340-356, ISSN: 1354-0793
  • JOURNAL ARTICLE
    Alroudhan A, Vinogradov J, Jackson MD, 2016,

    Zeta potential of intact natural limestone: Impact of potential-determining ions Ca, Mg and SO4

    , COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS, Vol: 493, Pages: 83-98, ISSN: 0927-7757
  • JOURNAL ARTICLE
    Baker DMH, Head JW, Collins GS, Potter RWKet al., 2016,

    The formation of peak-ring basins: Working hypotheses and path forward in using observations to constrain models of impact-basin formation

    , ICARUS, Vol: 273, Pages: 146-163, ISSN: 0019-1035

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