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Conference paperRimoy S, Jardine RJ, Standing JR, 2013,
Displacement response to axial cycling of driven piles in sand
, 18th Int. Conf. on Soil Mechanics and Geotchnical Engineering, Publisher: Presses des Ponts, Pages: 2387-2390 -
Conference paperJardine RJ, 2013,
Advanced laboratory testing in research and practice. 2nd Bishop Lecture
, 18th Conf. on Soil Mechanics and Geotechnical Engineering, Publisher: Presses des Ponts, Pages: 25-55 -
Conference paperSilva M, Foray P, Rimoy S, et al., 2013,
Influence des chargements cycliques axiaux sur le comportement et la capacité des pieux foncés dans les sables.
, Proc. 18th Int. Conf. on Soil Mechanics and Geotechnical Engineering, Publisher: Presses des Ponts, Pages: 2403-2406 -
Journal articlePelecanos L, Kontoe S, Zdravkovic L, 2013,
Numerical modelling of hydrodynamic pressures on dams
, Computers and Geotechnics, Vol: 53, Pages: 68-82This paper discusses several considerations related to appropriate numerical modelling of the reservoirhydrodynamic pressures on dams. The reservoir is modelled with 8-noded isoparametric displacementbased solid finite elements. The study includes both stiff and flexible dams with vertical and slopedupstream faces under ramp, harmonic and random acceleration loads. The numerical results were comparedand found to be in good agreement with available closed-form solutions. The same approach maybe used in analyses of other waterfront structures such as quay walls.
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Journal articleCorbett LB, Bierman PR, Graly JA, et al., 2013,
Constraining landscape history and glacial erosivity using paired cosmogenic nuclides in upernavik, northwest greenland
, Bulletin of the Geological Society of America, Vol: 125, Pages: 1539-1553, ISSN: 0016-7606High-latitude landscape evolution processes have the potential to preserve old, relict surfaces through burial by cold-based, nonerosive glacial ice. To investigate landscape history and age in the high Arctic, we analyzed in situ cosmogenic 10Be and 26Al in 33 rocks from Upernavik, northwest Greenland. We sampled adjacent bedrock-boulder pairs along a 100 km transect at elevations up to 1000 m above sea level. Bedrock samples gave significantly older apparent exposure ages than corresponding boulder samples, and minimum limiting ages increased with elevation. Two-isotope calculations (26Al/10Be) on 20 of the 33 samples yielded minimum limiting exposure durations up to 112 k.y., minimum limiting burial durations up to 900 k.y., and minimum limiting total histories up to 990 k.y. The prevalence of 10Be and 26Al inherited from previous periods of exposure, especially in bedrock samples at high elevation, indicates that these areas record long and complex surface exposure histories, including significant periods of burial with little subglacial erosion. The long total histories suggest that these highelevation surfaces were largely preserved beneath cold-based, nonerosive ice or snowfields for at least the latter half of the Quaternary. Because of high concentrations of inherited nuclides, only the six youngest boulder samples appear to record the timing of ice retreat. These six samples suggest deglaciation of the Upernavik coast at 11.3 ± 0.5 ka (average ± 1 standard deviation). There is no difference in deglaciation age along the 100 km sample transect, indicating that the ice-marginal position retreated rapidly at rates of ~120 m yr-1. © 2013 Geological Society of America.
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Journal articleSun T, Liu J, Yan H, et al., 2013,
Super-resolution reconstruction based on incoherent optical aperture synthesis
, OPTICS LETTERS, Vol: 38, Pages: 3471-3474, ISSN: 0146-9592- Author Web Link
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- Citations: 9
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Journal articleWilson P, Elliott GM, Gawthorpe RL, et al., 2013,
Geometry and segmentation of an evaporite-detached normal fault array: The southern Bremstein Fault Complex, offshore mid-Norway
, Journal of Structural Geology, Vol: 51, Pages: 74-91Geometry and segmentation of an evaporite-detached normal fault array: The southern Bremstein Fault Complex, offshore mid-Norway.
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Journal articleTvedt ABM, Rotevatn A, Jackson CAL, et al., 2013,
Growth of normal faults in multilayer sequences; a 3D seismic case study from the Egersund Basin, Norwegian North Sea
, Journal of Structural Geology, Vol: 55, Pages: 1-20We investigate the structural style and evolution of a salt-influenced, extensional fault array in the Egersund Basin (Norwegian North Sea) through analysis of 3D reflection seismic and well data. Analysis of fault geometry/morphology, throw distribution and syn-kinematic strata reveal an intricate but systematic style of displacement and growth, suggesting an evolution of (1) initial syn-sedimentary fault growth contemporaneous with salt mobilization initiated during the Late Triassic, (2) cessation of fault activity and burial of the stagnant fault tips, and (3) subsequent nucleation of new faults in the cover above contemporaneous salt re-mobilization initiated during the Late Cretaceous, with downward propagation and linkage with faults. Stage 3 was apparently largely controlled by salt mobilization in response to basin inversion, as reactivated faults are located where the underlying salt is thick, while the non-reactivated faults are found where salt is depleted. Based on the 3D-throw analyses, we conclude that a combination of basement faulting and salt (re-) mobilization is the driving mechanisms behind fault activation and reactivation. Even though the sub- and supra-salt faults are mainly geometrically decoupled through the salt, a kinematic coupling must have existed as sub-salt faults still affected nucleation and localization of the cover faults.
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Journal articleLewis MM, Jackson CAL, Gawthorpe RL, 2013,
Salt-influenced normal fault growth and forced folding; the Stavanger Fault System, North Sea
, Journal of Structural Geology, Vol: 54, Pages: 156-173Displacement ratio (Dr) is the ratio of salt thickness (Tv) to sub-salt normal fault displacement (D) (Dr = Tv /D), and it is typically used to predict the degree of geometric and kinematic linkage between sub- and supra-salt fault populations, and the overall resultant structural style in salt-influenced extensional settings. However, we currently lack natural examples of how Dr and the underlying geological controls vary, and how these may control the three-dimensional geometry and evolution of salt-influenced normal fault systems. Furthermore, it is currently unknown if kinematic coherence in salt-influenced extensional settings can be maintained over long length-scales (101-103 m) and for long periods of extension, and how this may impact the growth and geometry of large-throw (> 500 m), salt-influenced normal fault systems. In this paper we use a 3600 km2, high-quality 3D seismic reflection dataset and borehole data from the Stavanger Fault System (SFS), Egersund Basin, eastern North Sea Basin to investigate; (i) how pre-rift salt thickness (Tv) and sub-salt fault throw (T) control the structural style and evolution of a basin-bounding, salt-influenced normal fault system; and (ii) the role salt plays in maintaining kinematic coherence in normal fault systems. We demonstrate that; (i) pre-rift salt distribution (Tv), specifically its presence in the proto-footwall (i.e., when Tv > 0), is the primary control on partitioning of faulting and (forced) folding along the fault system, and the style of linkage (i.e., hard- or soft-linkage) between sub- and supra-salt fault populations; and (ii) that sub- and supra-salt fault populations represent brittle elements of single geometrically and kinematically coherent structure, which is related to the ductile translation of strain on a scale (up to 8 km) and duration (c. 65 Myr) that is significantly greater than previously documented.
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Journal articleGudmundsdottir MH, Blisniuk K, Ebert Y, et al., 2013,
Restraining bend tectonics in the santa cruz mountains, california, imaged using <sup>10</sup> be concentrations in river sands
, Geology, Vol: 41, Pages: 843-846, ISSN: 0091-7613Reverse faults frequently generate large and destructive earthquakes, yet their seismic hazard remains difficult to assess with traditional paleoseismic tools because their surface expressions are often complex and subtle. This contribution assesses the utility of millennial- scale denudation rates derived from in-situ cosmogenic 10Be for revealing the spatial patterns and magnitudes of rock uplift produced by slip along reverse faults. We present seventeen basin-averaged denudation rates from rivers draining the Santa Cruz Mountains along the San Andreas fault (California, USA) which closely reproduce known uplift rate patterns associated with a restraining bend along the fault. An additional component of vertical deformation appears to be superposed on the uplift due to the restraining bend; this may result from regional transpression, further irregularities in the fault trace, or interactions with neighboring faults. Our results indicate that 10Be-derived denudation rates can reveal patterns of rock uplift adjacent to reverse faults over length-scales relevant for characterizing their seismic hazard potential. © 2013 Geological Society of America.
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Journal articleHolgate NE, Jackson CA-L, Hampson GJ, et al., 2013,
Sedimentology and sequence stratigraphy of the Middle–Upper Jurassic Krossfjord and Fensfjord formations, Troll Field, northern North Sea
, Petroleum Geoscience, Vol: 19, Pages: 237-258, ISSN: 1354-0793<jats:p> The Middle–Upper Jurassic Krossfjord and Fensfjord formations are secondary reservoir targets in the super-giant Troll oil and gas field, Horda Platform, offshore Norway. The formations comprise sandstones ( <jats:italic>c</jats:italic> . 195 m thick) sourced from the Norwegian mainland to the east, that pinch out basinwards into offshore shales of the Heather Formation to the west. Sedimentological analysis of cores from the Troll Field has identified six facies associations, which represent wave- and tide-dominated deltaic, shoreline and shelf depositional environments. Resulting depositional models highlight the complex distribution of depositional environments, and reflect spatial and temporal variations in physical processes at the shoreline, rate of sediment supply and accommodation development. These models are further complicated by the absence of coastal plain facies, which implies that the Troll Field was fully subaqueous during deposition, that shoreline regression was forced by falling sea level or that coastal plain deposits were removed by transgression. Genetic sequences bounded by major flooding surfaces (‘series’) exhibit laterally uniform thicknesses, implying no major tectonic influence on sedimentation. The recognition of pronounced variability in facies character and stratigraphical architecture emphasize the need for a robust depositional model of the formations in order to drive future exploration in these, and coeval, reservoirs. </jats:p>
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Journal articleRimoy SP, Jardine RJ, Standing JR, 2013,
Displacement response to axial cycling of piles driven in sand
, ICE Proceedings Geotechnical Engineering -
Journal articleLegler B, Johnson HD, Hampson GJ, et al., 2013,
Facies model of a fine-grained, tide-dominated delta: lower Dir Abu Lifa Member (Eocene), Western Desert, Egypt
, Sedimentology, Vol: 60, Pages: 1313-1356Existing facies models of tide-dominated deltas largely omit fine-grained, mud-rich successions. Sedimentary facies and sequence stratigraphic analysis of the exceptionally well-preserved Late Eocene Dir Abu Lifa Member (Western Desert, Egypt) aims to bridge this gap. The succession was deposited in a structurally controlled, shallow, macrotidal embayment and deposition was supplemented by fluvial processes but lacked wave influence. The succession contains two stacked, progradational parasequence sets bounded by regionally extensive flooding surfaces. Within this succession two main genetic elements are identified: non-channelised tidal bars and tidal channels. Non-channelised tidal bars comprise coarsening-upward sand bodies, including large, downcurrent-dipping accretion surfaces, sometimes capped by palaeosols indicating emergence. Tidal channels are preserved as single-storey and multilateral bodies filled by: (i) laterally migrating, elongate tidal bars (inclined heterolithic strata, 5 to 25 m thick); (ii) forward-facing lobate bars (sigmoidal heterolithic strata, up to 10 m thick); (iii) side bars displaying oblique to vertical accretion (4 to 7 m thick); or (iv) vertically-accreting mud (1 to 4 m thick). Palaeocurrent data show that channels were swept by bidirectional tidal currents and typically were mutually evasive. Along-strike variability defines a similar large-scale architecture in both parasequence sets: a deeply scoured channel belt characterised by widespread inclined heterolithic strata is eroded from the parasequence-set top, and flanked by stacked, non-channelised tidal bars and smaller channelised bodies. The tide-dominated delta is characterised by: (i) the regressive stratigraphic context; (ii) net-progradational stratigraphic architecture within the succession; (iii) the absence of upward deepening trends and tidal ravinement surfaces; and (iv) architectural relations that demonstrate contemporaneous tidal distributary channel infill and ti
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Journal articleLiu Y, Cao X, Liu JG, 2013,
Classification using distances from samples to linear manifolds
, PATTERN ANALYSIS AND APPLICATIONS, Vol: 16, Pages: 417-430, ISSN: 1433-7541- Author Web Link
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- Citations: 1
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Journal articleCraske JC, van Reeuwijk M, 2013,
Robust and accurate open boundary conditions for incompressible turbulent jets and plumes
, Computers and FluidsWe show that a popular convective open boundary condition (OBC) is unsuitable in the direct simulation of incompressible turbulent jets and plumes, because (1) the boundary condition modifies their spreading rate; (2) the results are domain dependent; and (3) the boundary condition is liable to cause instability and therefore requires domains that are much larger than the area of interest. We demonstrate the accuracy of new axisymmetric OBCs compared to the standard OBC by conducting direct numerical simulation (DNS) of a turbulent plume and a turbulent jet. The new OBCs conform to the fundamental features of statistically axisymmetric turbulent flows, regardless of the computational domains on which they are imposed. They do not contain tunable parameters and are dynamical, accounting for the strength and extent of a flow at a given time, which eliminates the need for calibration to particular cases. The implementation presented herein is computationally efficient and robust in the vicinity of turbulent flows
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Journal articleSookhak Lari K, Reeuwijk M, Maksimović Č, 2013,
The role of geometry in rough wall turbulent mass transfer
, Heat and Mass Transfer, Vol: 49, Pages: 1191-1203, ISSN: 0947-7411 -
Journal articleJackson CAL, Rotevatn A, 2013,
3D seismic analysis of the structure and evolution of a salt-influenced normal fault zone: a test of competing fault growth models
, Journal of Structural Geology, Vol: 54, Pages: 215-234In this paper we determine the structure and evolution of a normal fault system by applying qualitative and quantitative fault analysis techniques to a 3D seismic reflection dataset from the Suez Rift, Egypt. Our analysis indicates that the October Fault Zone is composed of two fault systems that are locally decoupled across an salt-bearing interval of Late Miocene (Messinian) age. The sub-salt system offsets pre-rift crystalline basement, and was active during the Late Oligocene-early Middle Miocene. It is composed of four, planar, NW-SE-striking segments that are hard-linked by N-S-striking segments, and up to 2 km of displacement occurs at top basement, suggesting that this fault system nucleated at or, more likely, below this structural level. The supra-salt system was active during the Pliocene-Holocene, and is composed of four, NW-SE-striking, listric fault segments, which are soft-linked by unbreached relay zones. Segments in the supra-salt fault system nucleated within Pliocene strata and have maximum throws of up to 482 m. Locally, the segments of the supra-salt fault system breach the Messinian salt to hard-link downwards with the underlying, sub-salt fault system, thus forming the upper part of a fault zone composed of: (i) a single, amalgamated fault system below the salt and (ii) a fault system composed of multiple soft-linked segments above the salt. Analysis of throw-distance (T-x) and throw-depth (T-z) plots for the supra-salt fault system, isopach maps of the associated growth strata and backstripping of intervening relay zones indicates that these faults rapidly established their lengths during the early stages of their slip history. The fault tips were then effectively ‘pinned’ and the faults accumulated displacement via predominantly downward propagation. We interpret that the October Fault Zone had the following evolutionary trend; (i) growth of the sub-salt fault system during the Oligocene-to-early Middle Miocene; (ii) cessation of
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Conference paperBland PA, Collins GS, Dyl KA, et al., 2013,
Impact-induced compaction of primordial materials and the effect on the chondrite record.
, 76th Annual Meeting of the Meteoritical-Society, Publisher: WILEY-BLACKWELL, Pages: A63-A63, ISSN: 1086-9379 -
Journal articleKimura S, Candy AS, Holland PR, et al., 2013,
Adaptation of an unstructured-mesh, finite-element ocean model to the simulation of ocean circulation beneath ice shelves
, Ocean Modelling, Vol: 67, Pages: 39-51, ISSN: 1463-5003 -
Journal articleAmos CB, Brownlee SJ, Rood DH, et al., 2013,
Chronology of tectonic, geomorphic, and volcanic interactions and the tempo of fault slip near Little Lake, California
, Bulletin of the Geological Society of America, Vol: 125, Pages: 1187-1202, ISSN: 0016-7606New geochronologic and geomorphic constraints on the Little Lake fault in the Eastern California shear zone reveal steady, modest rates of dextral slip during and since the midto-late Pleistocene. We focus on a suite of offset fluvial landforms in the Pleistocene Owens River channel that formed in response to peri odic interaction with nearby basalt flows, thereby recording displacement over multiple time intervals. Overlap between 40Ar/39Ar ages for the youngest intracanyon basalt flow and 10Be surface exposure dating of downstream terrace surfaces suggests widespread channel incision during a prominent outburst flood through the Little Lake channel at ca. 64 ka. Older basalt flows flanking the upper and lower canyon margins indicate localization of the Owens River in its current position between 212 ± 14 and 197 ± 11 ka. Coupled with terrestrial light detection and ranging (lidar) and digital topographic measurements of dextral offset, the revised Little Lake chronology indicates average dextral slip rates of at least ~0.6-0.7 mm/yr and <1.3 mm/yr over intervals ranging from ~104 to 105 yr. Despite previous geodetic observations of relatively rapid interseismic strain along the Little Lake fault, we find no evidence for sustained temporal fluctuations in slip rates over multiple earthquake cycles. Instead, our results indicate that accelerated fault loading may be transient over much shorter periods (~101 yr) and perhaps indicative of time-dependent seismic hazard associated with Eastern California shear zone faults. © 2013 Geological Society of America.
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