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  • JOURNAL ARTICLE
    Patruno S, Hampson GJ, Jackson CA-L, 2015,

    Quantitative characterisation of deltaic and subaqueous clinoforms

    , EARTH-SCIENCE REVIEWS, Vol: 142, Pages: 79-119, ISSN: 0012-8252
  • JOURNAL ARTICLE
    Patruno S, Hampson GJ, Jackson CA-L, Dreyer Tet al., 2015,

    Clinoform geometry, geomorphology, facies character and stratigraphic architecture of a sand-rich subaqueous delta: Jurassic Sognefjord Formation, offshore Norway

    , Sedimentology, Vol: 62, Pages: 350-388

    The integration of core sedimentology, seismic stratigraphy and seismic geomorphology has enabled interpretation of a sand-prone subaqueous delta in the Upper Jurassic Sognefjord Formation of the Troll Field, Horda Platform, offshore Norway. Mud-prone subaqueous deltas characterised by a compound clinoform morphology are common in many modern tide- and wave-influenced settings, but ancient examples are rarely reported. The Sognefjord Formation data therefore demonstrate the criteria for recognition of subaqueous deltas in the stratigraphic record, as well as refining the depositional model of the main reservoir in the super-giant Troll oil and gas field. Two 10-60 m thick, wave-dominated, regressive-transgressive packages bounded by major marine flooding surfaces are distinguished in the lower Sognefjord Formation. Each regressive-transgressive package corresponds to a set of seismically resolved, westerly-dipping clinoforms, and its bounding surfaces form the seismic “envelope” of a clinoform set. The packages thicken westwards, until they reach a maximum where the clinoform “envelope” rolls over to define a topset-foreset-toeset geometry at the position of maximum regression. Both individual clinoforms and reflections bounding the clinoform sets are oriented sub-parallel to the edge of the Horda Platform (N005-N030). In the eastern half of the field, individual clinoforms are relatively gently dipping (1°-6°) and bound thin (10-30 m) clinothems dominated by fine-grained, hummocky cross-stratified sandstones. Towards the west, clinoforms gradually become steeper (5°-14°) and bound thicker (15-60 m) clinothems that comprise medium-grained, cross-bedded sandstones in their upper parts. Topsets are consistently well developed, except in the westernmost area, where some clinoform foresets are top-truncated. No evidence of subaerial exposure is observed. We interpret deposition by fully subaqueous, near-linear clinoforms that pro

  • JOURNAL ARTICLE
    Patruno S, Hampson GJ, Jackson CA-L, Whipp PSet al., 2015,

    Quantitative progradation dynamics and stratigraphic architecture of ancient shallow-marine clinoform sets: a new method and its application to the Upper Jurassic Sognefjord Formation, Troll Field, offshore Norway

    , BASIN RESEARCH, Vol: 27, Pages: 412-452, ISSN: 0950-091X
  • JOURNAL ARTICLE
    Pelecanos L, Kontoe S, Zdravkovic L, 2015,

    A case study on the seismic performance of earth dams

    , GEOTECHNIQUE, Vol: 65, Pages: 923-935, ISSN: 0016-8505
  • SOFTWARE
    Piggott MD, 2015,

    OpenTidalFarm

    OpenTidalFarm is an open-source software for simulating and optimising tidal turbine farms.The positioning of the turbines in a tidal farm is a crucial decision. Simulations show that the optimal positioning can increase the power generation of the farm by up to 50% and can therefore determine the viability of a project. However, finding the optimal layout is a difficult process due to the complex flow interactions. OpenTidalFarm solves this problem by applying an efficient optimisation algorithm onto a accurate flow prediction model.

  • JOURNAL ARTICLE
    Portenga EW, Bierman PR, Duncan C, Corbett LB, Kehrwald NM, Rood DHet al., 2015,

    Erosion rates of the Bhutanese Himalaya determined using in situ-produced Be-10

    , GEOMORPHOLOGY, Vol: 233, Pages: 112-126, ISSN: 0169-555X
  • JOURNAL ARTICLE
    Potter RWK, Kring DA, Collins GS, 2015,

    Scaling of basin-sized impacts and the influence of target temperature

    , Special Paper of the Geological Society of America, Vol: 518, Pages: 99-113, ISSN: 0072-1077

    © 2015 The Geological Society of America. All rights reserved. We produce a set of scaling laws for basin-sized impacts using data from a suite of lunar basin numerical models. The results demonstrate the importance of preimpact target temperature and thermal gradient, which are shown to greatly influence the modification phase of the impact cratering process. Impacts into targets with contrasting thermal properties also produce very different crustal and topographic profiles for impacts of the same energy. Thermal conditions do not, however, significantly influence the excavation stage of the cratering process; results demonstrate, as a consequence of gravity-dominated growth, that transient crater radii are generally within 5% of each other over a wide range of thermal gradients. Excava tion depth-to-diameter ratios for the basin models (~0.12) agree well with experimental, geological, and geophysical estimates, suggesting basins follow proportional scaling. This is further demonstrated by an agreement between the basin models and Piscaling laws based upon first principles and experimental data. The results of this work should also be applicable to basin-scale impacts on other silicate bodies, including the Hadean Earth.

  • JOURNAL ARTICLE
    Prelat A, Hodgson DM, Hall M, Jackson CA-L, Baunack C, Tveiten Bet al., 2015,

    Constraining sub-seismic deep-water stratal elements with electrofacies analysis; A case study from the Upper Cretaceous of the Maloy Slope, offshore Norway

    , MARINE AND PETROLEUM GEOLOGY, Vol: 59, Pages: 268-285, ISSN: 0264-8172
  • JOURNAL ARTICLE
    Prelat A, Pankhania S, Jackson CA-L, Hodgson DMet al., 2015,

    Slope gradient and lithology as controls on the initiation of submarine slope gullies; insights from the North Carnarvon Basin, Offshore NW Australia

    , Sedimentary Geology, Vol: 329, Pages: 12-17, ISSN: 0037-0738

    Slope-confined submarine gullies are present on many continental margins, yet the controls on their initiation and demise are poorly understood because modern or recently active systems are rarely if ever monitored, and exhumed systems, typically formed in very fine-grained successions, are poorly preserved at outcrop. We use 3D seismic reflection and borehole data from offshore NW Australia to investigate long-term (~ 40 Myr) variations in the geomorphology of Eocene-to-Miocene gullies that developed in mixed carbonate–clastic clinothems. Through time, clinoform slope gradient increases from 1.6° to 3.2°, with gullies forming when the clinoform slope exceeds 2.5°. After their inception, gullies increase in width (from 350 m to 770 m) and depth (from 37 m to 60 m). Slope steepening appears to coincide with a change from poorly cemented, fine-grained carbonate to better-cemented, coarse-grained carbonate, implying a secondary, lithological control on slope dip and, ultimately, gully formation.

  • JOURNAL ARTICLE
    Pupim FDN, Bierman PR, Assine ML, Rood DH, Silva A, Merino ERet al., 2015,

    Erosion rates and landscape evolution of the lowlands of the Upper Paraguay river basin (Brazil) from cosmogenic Be-10

    , GEOMORPHOLOGY, Vol: 234, Pages: 151-160, ISSN: 0169-555X
  • JOURNAL ARTICLE
    Reeve MT, Bell RE, Duffy O, Jackson CAL, Sansom E, Reeve MT, Bell RE, Duffy OB, Jackson CA-L, Sansom Eet al., 2015,

    The development of non-colinear fault systems; what can we learn from 3D seismic reflection data?

    , Journal of Structural Geology, Vol: 70, Pages: 141-155, ISSN: 0191-8141

    Many rift zones exhibit a range of fault orientations, rather than simple colinear faults that strike orthogonal to the inferred least principal stress. The formation of non-colinear fault sets has implications for assessing rift-zone kinematics, as well as determining palaeo-stress state in extensional basins. Using 3D seismic reflection data, we deduce the likely mechanisms responsible for the formation of a population of non-colinear faults in the Måløy Slope area of the northern North Sea. Three basement-displacing fault populations exist on the Måløy Slope; (i) large (>1 km throw), N-S-striking faults, (ii) smaller (<250 m throw) N-S-striking faults and (iii) small (<250m throw) NE-SW-striking faults. All were initiated in the Middle Jurassic. Coeval growth of these fault populations, and the apparent correlation between the NE-SW faults and a NE-SW-trending gravity and magnetic anomaly high lead us to suggest that the NE-SW faults are the result of deflection of the otherwise E-W-orientated least principal stress by NE-trending intrabasement weaknesses. Our study’s results have implications for the large-scale kinematic evolution of the North Sea, arguing that major rotations in extension direction are not required to generate multiple fault sets locally or across the rift. This study also highlights the importance of using borehole-constrained 3D seismic data as a tool in understanding non-colinear fault growth, and its broader implications for regional tectonic history.

  • JOURNAL ARTICLE
    Reusser L, Bierman P, Rood D, 2015,

    Quantifying human impacts on rates of erosion and sediment transport at a landscape scale

    , GEOLOGY, Vol: 43, Pages: 171-174, ISSN: 0091-7613
  • CONFERENCE PAPER
    Rimoy SP, Jardine RJ, 2015,

    Axial capacity ageing trends of piles driven in silica sands

    , Pages: 637-642

    © 2015 Taylor and Francis Group, London. Field studies of piles driven in silica sands have shown axial capacity increases (set-up) over the days to months that follow driving, long after installation induced pore pressures have dissipated. Three main hypotheses have been proposed regarding the governing mechanisms and tested to a limited extent through relatively modest databases of pile load tests. However, a secure understanding of the governing mechanisms is required before projecting ageing predictions for other cases and considering how ageing trends might be affected by, for example, scale, pile type, groundwater regime or submerged offshore conditions. This paper reports an extended database study aimed at assessing the distinct ageing contributions of base and shaft loads, the potential influence of compression or tension axial loading directions, the effects of prior loading history, the influence of groundwater type as well as the effects of pile diameter and material. The analysis is informed by parallel highly instrumented model tests that were designed to investigate and identify the fundamental ageing mechanisms. The findings have important implications for pile design and re-assessment.

  • CONFERENCE PAPER
    Rimoy SP, Jardine RJ, 2015,

    Analysis of an extended field test database regarding driven pile ageing in sands

    , Pages: 1157-1162

    © The authors and ICE Publishing: All rights reserved, 2015. Field testing has revealed that the axial capacities of piles driven in sand can increase dramatically with age after driving. Jardine et al (2006) showed from experiments conducted in Dunkirk that the processes are affected by the history of prior loading and assembled a modest database of field cases to support the evidence from their single test site. This paper reports an extended database that is used to assess: The distinct contributions of base and shaft loads; the potential influence of loading sign (compression or tension); the effects of any prior failures; the influence of groundwater type as well as the effects of pile diameter and material. The analysis presented is informed by parallel highly instrumented model tests that were designed to explore the fundamental driving mechanisms. The findings have important implications for the re-assessment and re-use of foundations in a wide range of onshore and offshore project settings.

  • JOURNAL ARTICLE
    Shanks RP, Ascough PL, Dougans A, Gallacher P, Gulliver P, Rood DH, Xu S, Freeman SPHTet al., 2015,

    Performance of the rebuilt SUERC single-stage accelerator mass spectrometer

    , Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms, Vol: 361, Pages: 76-79, ISSN: 0168-583X

    © 2015 The Authors. The SUERC bipolar single-stage accelerator mass spectrometer (SSAMS) has been dismantled and rebuilt to accommodate an additional rotatable pre-accelerator electrostatic spherical analyser (ESA) and a second ion source injector. This is for the attachment of an experimental positive-ion electron cyclotron resonance (ECR) ion source in addition to a Cs-sputter source. The ESA significantly suppresses oxygen interference to radiocarbon detection, and remaining measurement interference is now thought to be from 13 C injected as 13 CH molecule scattering off the plates of a second original pre-detector ESA.

  • JOURNAL ARTICLE
    Stafford PJ, 2015,

    Variability and Uncertainty in Empirical Ground-Motion Prediction for Probabilistic Hazard and Risk Analyses

    , PERSPECTIVES ON EUROPEAN EARTHQUAKE ENGINEERING AND SEISMOLOGY, VOL 2, Vol: 39, Pages: 97-128
  • JOURNAL ARTICLE
    Stafford PJ, 2015,

    Extension of the Random-Effects Regression Algorithm to Account for the Effects of Nonlinear Site Response

    , BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA, Vol: 105, Pages: 3196-3202, ISSN: 0037-1106
  • JOURNAL ARTICLE
    Stevenson CJ, Jackson CA-L, Hodgson DM, Hubbard SM, Eggenhuisen JTet al., 2015,

    Deep-water sediment bypass

    , Journal of Sedimentary Research, Vol: 85, Pages: 1058-1081, ISSN: 1527-1404

    Submarine gravity flows are a key process for transporting large volumes of sediment from the continents to the deep sea. The location, volume, and character of the sediment bypassed by these flows dictates the areal extent and thickness of the associated deposits. Despite its importance, sediment bypass is poorly understood in terms of flow processes and the associated stratigraphic expression. We first examine the relationships between the physical parameters that govern bypass in flows, before assessing the variable stratigraphic expression of bypass from modern seafloor, outcrop, and subsurface datasets. Theoretical and numerical approaches distinguish grain size, slope, flow size, and sediment concentration as parameters that exert major controls on flow bypass. From field data, a suite of criteria are established to recognize bypass in the geological record. We identify four bypass-dominated zones, each of which is associated with a set of diagnostic criteria: slope-channel bypass, slope-bypass from mass wasting events, base-of-slope bypass, and basin-floor bypass. As the expression of bypass varies spatially and is dependent on the scale of observation, a range of scale-dependent criteria are required for robust interpretation of these zones in the field or subsurface. This synthesis of deep-water sediment bypass highlights the challenge in quantitatively linking process with product. The establishment of criteria to recognize sediment bypass, qualitatively linked with flow processes, is an important step towards improving our understanding of submarine flow dynamics and resultant stratigraphic architecture.

  • JOURNAL ARTICLE
    Stewart JP, Douglas J, Javanbarg M, Bozorgnia Y, Abrahamson NA, Boore DM, Campbell KW, Delavaud E, Erdik M, Stafford PJet al., 2015,

    Selection of Ground Motion Prediction Equations for the Global Earthquake Model

    , EARTHQUAKE SPECTRA, Vol: 31, Pages: 19-45, ISSN: 8755-2930
  • JOURNAL ARTICLE
    Su K, Latham J-P, Pavlidis D, Xiang J, Fang F, Mostaghimi P, Percival JR, Pain CC, Jackson MDet al., 2015,

    Multiphase flow simulation through porous media with explicitly resolved fractures

    , GEOFLUIDS, Vol: 15, Pages: 592-607, ISSN: 1468-8115

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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