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Journal articleMagee C, Briggs F, Jackson CAL, 2013,
3D seismic insights into lithological controls on igneous intrusion-induced ground deformation
, Journal of the Geological Society, Vol: 170, Pages: 853-856Ground deformation commonly precedes volcanic eruptions, although its relationship to underlying intrusion networks is complex. We use 3D seismic reflection data to examine the link between a saucer-shaped sill and an overlying forced fold formed at the contemporaneous palaeosurface. Our results highlight a disparity in size between the sill and fold, which we attribute to accommodation of magma by overburden uplift and fluid expulsion from the host rock. Sill transgression occurred in response to plastic deformation of the host rock and did not produce seismically resolvable uplift. Inversion models of ground deformation should therefore acknowledge host rock behaviour during intrusion.
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Conference paperHolford SP, Schofield N, Jackson CAL, et al., 2013,
Impact of igneous intrusions on source and reservoir potential in prospective sedimentary basins
, Western Australia Basin SymposiumMany prospective basins in rifted continental margins, including those located along the western Australian continental margin, contain extrusive and intrusive rocks generated during rifting and particularly during continental breakup. Intrusive igneous systems in rifted margin basins are typically characterized by networks of interconnected, laterally and vertically extensive sheet complexes (e.g. sills and dykes) that transgress basin stratigraphy. The presence of igneous rocks thus represents an important geological risk in hydrocarbon exploration. Constraining the distribution, timing and intrusive mechanisms of the igneous rocks is essential to reducing exploration risk. This paper focuses on two key sources of risk associated with the intrusion of igneous rocks into prospective sedimentary basins: (1) interconnected, low-permeability sheet intrusions (e.g. sills and dykes) that can compartmentalise significant volumes of source and reservoir rock, thereby reducing migration efficiencies; and (2) igneous-related hydrothermal circulation systems that can be highly mineralising and thus detrimental to reservoir quality. It is also important to highlight that igneous rocks may also be beneficial to petroleum systems. For example, the thermal effects of igneous intrusions may in some cases be sufficient to place immature source rocks within the oil window. The impacts of igneous intrusion on the prospectivity of rift basins along the western Australian continental margin are examined, with particular focus on frontier exploration areas such as the Exmouth Plateau and Browse Basin.
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Journal articleWu M-C, Liu JG, Mason PJ, 2013,
Adaptive local kriging to retrieve slant-range surface motion maps of the Wenchuan earthquake
, INTERNATIONAL JOURNAL OF REMOTE SENSING, Vol: 34, Pages: 7589-7606, ISSN: 0143-1161- Author Web Link
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- Citations: 5
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Journal articleMiljkovic K, Wieczorek MA, Collins GS, et al., 2013,
Asymmetric Distribution of Lunar Impact Basins Caused by Variations in Target Properties
, Science, Vol: 342, Pages: 724-726, ISSN: 0036-8075Maps of crustal thickness derived from NASA’s Gravity Recovery and Interior Laboratory (GRAIL) mission revealed more large impact basins on the nearside hemisphere of the Moon than on its farside. The enrichment in heat-producing elements and prolonged volcanic activity on the lunar nearside hemisphere indicate that the temperature of the nearside crust and upper mantle was hotter than that of the farside at the time of basin formation. Using the iSALE-2D hydrocode to model impact basin formation, we found that impacts on the hotter nearside would have formed basins with up to twice the diameter of similar impacts on the cooler farside hemisphere. The size distribution of lunar impact basins is thus not representative of the earliest inner solar system impact bombardment.
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Journal articleAmidon WH, Bookhagen B, Avouac JP, et al., 2013,
Late Pleistocene glacial advances in the western Tibet interior
, Earth and Planetary Science Letters, Vol: 381, Pages: 210-221, ISSN: 0012-821XIt has long been observed that the timing of glacial advances is asynchronous across the Himalaya-Karakoram-Tibet Plateau (HKTP) but the climatic implications, if any, remain unclear. Resolving this question requires additional glacial chronologies from unique spatial and climatic regimes as well as an analysis of how glaciers within different regimes are likely to have responded to past climate changes. This study presents a 10Be-21Ne chronology from the Mawang Kangri range of western Tibet (~34°N, 80°E); an arid high-elevation site. We identify advances at ~123, 83, and 56 kyr, which agree reasonably well with sites in the immediate vicinity, but are asynchronous relative to sites across the entire HKTP, and relative to sites in the western HKTP. To evaluate HKTP-wide asynchroneity, we compile dated glacial chronologies and classify them by the approximate timing of their maximum recent advance. This result shows a strong spatial clustering of young (MIS 1-2) relative to older (MIS 3-5) maximum advances. Further comparison with modern precipitation, temperature, and topographic data show that the pattern of HKTP-wide asynchroneity is broadly independent of topography and can potentially be explained by local responses to changes in temperature at either very warm-wet or cold-dry sites. Sites that receive intermediate amounts of precipitation are more ambiguous, although spatial clustering of MIS 1-2 vs. MIS 3-5 advances is suggestive of past variations in precipitation at these sites. In western Tibet, no spatial or climatic correlation is observed with the timing of maximum glacial advances. We suggest this could arise from mis-interpretation of disparate boulder ages generated by a prolonged MIS-3/4 glacial advance in the western HKTP. © 2013 Elsevier B.V.
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Journal articleDilib FA, Jackson MD, 2013,
Closed-Loop Feedback Control for Production Optimization of Intelligent Wells Under Uncertainty
, SPE PRODUCTION & OPERATIONS, Vol: 28, Pages: 345-357, ISSN: 1930-1855- Author Web Link
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- Citations: 14
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Journal articleJackson CA-L, Lewis MM, 2013,
Physiography of the NE margin of the Permian Salt Basin: new insights from 3D seismic reflection data
, JOURNAL OF THE GEOLOGICAL SOCIETY, Vol: 170, Pages: 857-860, ISSN: 0016-7649- Author Web Link
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- Citations: 16
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Journal articleJackson CAL, Schofield N, Golenkov B, 2013,
Geometry and controls on the development of igneous sill-related forced folds: a 2D seismic reflection case study from offshore southern Australia
, Geological Society of America Bulletin, Vol: 125, Pages: 1874-1890Emplacement of magma in the shallow subsurface can result in the development of dome–shaped folds at the Earth's surface. These so-called "forced folds" have been described in the field and in subsurface data sets, although the exact geometry of the folds and the nature of their relationship to underlying sills remain unclear and, in some cases, controversial. In this study we use high-quality, two-dimensional (2-D) seismic reflection and borehole data from the Ceduna sub-basin, offshore southern Australia, to describe the structure and infer the evolution of igneous sill–related forced folds in the Bight Basin igneous complex. Thirty-three igneous sills, which were emplaced 200–1500 m below the paleo-seabed in Upper Cretaceous rocks, are mapped in the Ceduna sub-basin. The intrusions are expressed as packages of high-amplitude reflections, which are 32–250 m thick and 7–19 km in diameter. We observe five main types of intrusion: type 1, strata-concordant sills; type 2, weakly strata-discordant, transgressive sills; type 3, saucer-shaped sills; type 4, laccoliths; and type 5, hybrid intrusions, which have geometric characteristics of intrusion types 1–3. These intrusions are overlain by dome-shaped folds, which are up to 17 km wide and display up to 210 m of relief. The edges of these folds coincide with the margins of the underlying sills and the folds display the greatest relief where the underlying sills are thickest; the folds are therefore interpreted as forced folds that formed in response to emplacement of magma in the shallow subsurface. The folds are onlapped by Lutetian (middle Eocene) strata, indicating they formed and the intrusions were emplaced during the latest Ypresian (ca. 48 Ma). We demonstrate that fold amplitude is typically less than sill thickness even for sills with very large diameter-to-depth ratios, suggesting that pure elastic bending (forced folding) of the overburden is not the only process a
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Journal articleMichael NA, Whittaker AC, Allen PA, 2013,
The functioning of sediment routing systems using a mass balance approach: Example from the Eocene of the southern Pyrenees
, Journal of Geology, Vol: 121, Pages: 581-606 -
Journal articleMorgan JV, Warner MR, Bell R, et al., 2013,
Next-generation seismic experiments: wide-angle, multi-azimuth,three-dimensional, full-waveform inversion
, Geophysical Journal International, Vol: in pressFull-waveform inversion (FWI) is an advanced seismic imaging technique that has recentlybecome computationally feasible in three dimensions, and that is being widely adopted andapplied by the oil and gas industry. Here we explore the potential for 3-D FWI, when combinedwith appropriate marine seismic acquisition, to recover high-resolution high-fidelity P-wavevelocity models for subsedimentary targets within the crystalline crust and uppermost mantle.We demonstrate that FWI is able to recover detailed 3-D structural information within aradially faulted dome using a field data set acquired with a standard 3-D petroleum-industrymarine acquisition system. Acquiring low-frequency seismic data is important for successfulFWI; we show that current acquisition techniques can routinely acquire field data from airgunsat frequencies as low as 2 Hz, and that 1 Hz acquisition is likely to be achievable using oceanbottomhydrophones in deep water. Using existing geological and geophysical models, weconstruct P-wave velocity models over three potential subsedimentary targets: the Soufri`ereHills Volcano on Montserrat and its associated crustal magmatic system, the crust and uppermostmantle across the continent–ocean transition beneath the Campos Basin offshore Brazil,and the oceanic crust and uppermost mantle beneath the East Pacific Rise mid-ocean ridge.Weuse these models to generate realistic multi-azimuth 3-D synthetic seismic data, and attempt toinvert these data to recover the original models.We explore resolution and accuracy, sensitivityto noise and acquisition geometry, ability to invert elastic data using acoustic inversion codes,and the trade-off between low frequencies and starting velocity model accuracy.We show thatFWI applied to multi-azimuth, refracted, wide-angle, low-frequency data can resolve featuresin the deep crust and uppermost mantle on scales that are significantly better than can beachieved by any other geophysical technique, and that these results ca
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Journal articleLari KS, van Reeuwijk M, Maksimovic C, 2013,
The role of geometry in rough wall turbulent mass transfer (vol 49, pg 1191, 2013)
, HEAT AND MASS TRANSFER, Vol: 49, Pages: 1523-1523, ISSN: 0947-7411- Author Web Link
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- Citations: 1
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Journal articleZakaria AA, Johnson HD, Jackson CAL, et al., 2013,
Sedimentary facies analysis and depositional model for the Palaeogene West Crocker submarine fan system, NW Borneo
, Journal of Asian Earth Sciences, Vol: 76, Pages: 283-300This study outlines a sedimentological analysis of the Palaeogene West Crocker Formation (WCF) around the Kota Kinabalu area of SW Sabah, which represents a large submarine fan depositional system within part of what was the complex and tectonically active margin of NW Borneo. The newly acquired and often extensive outcrop data summarised in this study has resulted in a more complete synthesis of the Crocker fan depositional system than has been previously possible. Seven facies (F1 to F7) have been identified which constitute three main facies groups: (1) sand-dominated facies (F1 to F3), comprise high- to low-density turbidites and form the dominant part of the WCF, (2) debris flow-dominated facies (F4 to F6) comprises mud- and sand-dominant debris flows and mass transport deposits (MTD), which form a secondary but highly distinctive part of the WCF, and (3) mudstone-dominated facies (F7), represent a subordinate part of the WCF. Analysis of the vertical facies successions (from proximal to distal), has resulted in recognition of five major genetic units: (1) Channel-levee complex; characterised by thick (30-60 m) thinning and fining upward facies succession, which are dominated in their lower part by thick-bedded (1-6 m), amalgamated high-density (Lowe-type) turbidites with rare debrite beds; the upper part is dominated low-density (Bouma-type) turbidites, without associated debrite beds. (2) Channelised lobes; characterized by 2-10 m thick, coarsening upward, which are overlain by 5-20 m thick fining upward facies successions; these successions are dominated by high-density turbidites (c. 0.5-1 m thick) and linked co-genetic turbidite-debrite beds (0.1-0.5 m thick), with subordinate mudstone facies. (3) Non-channelised lobes; comprise 5-20 m thick coarsening upward facies successions; these start with mudstone facies, which pass gradually upwards into linked co-genetic turbidite-debrite beds; sandstone bed thickness increases upwards, while the debrite caps tend
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Journal articleJonker HJJ, van Reeuwijk M, Sullivan PP, et al., 2013,
On the scaling of shear-driven entrainment: a DNS study
, Journal of Fluid Mechanics, Vol: 732, Pages: 150-165, ISSN: 0022-1120The deepening of a shear-driven turbulent layer penetrating into stably stratified quiescent layer is studied using Direct Numerical Simulation (DNS). The simulation design mimics the classical laboratory experiments by Kato and Phillips (J. Fluid Mech. 37, 643–655, 1969) in that it starts with linear stratification and applies a constant shear stress at the lower boundary, but avoids inherent side wall and rotation effects of that experiment. It is found that the layers universally deepen as a function of the square root of time, independent of the initial stratification and the Reynolds number of the simulations, provided that the Reynolds number is large enough. Consistent with this finding, the dimensionless entrainment velocity varies with the bulk Richardson number as Ri−1/2 . In addition it is observed that all cases evolve in a self-similar fashion. A selfsimilarity analysis of the conservation equations shows that only a square root growth law is consistent with self-similar behaviour.
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Journal articleSomme TO, Jackson CAL, 2013,
Source-to-sink analysis of ancient sedimentary systems using a subsurface case study from the Møre-Trøndelag area of southern Norway: Part 2 – sediment dispersal and forcing mechanisms
, Basin Research, Vol: 25, Pages: 512-531, ISSN: 0950-091XThe composition, volume and stratigraphic organisation of submarine fan systems deposited along continental margins are expected to reflect the landscape from which the sediment was derived. During the Late Cretaceous, the Møre-Trøndelag margin, Norwegian North Sea was dominated by the deposition of deep-marine fines; the emplacement of 11 sand-rich submarine fan systems occurred only during a c. 3 Myr period in the Turonian-Coniacian. The systems were fed by sediment that was routed through submarine canyons incised into the basin margin; the canyons are underlain by angular unconformities and are interpreted to have resulted from tectonically-induced changes in slope physiography and erosion by gravity flows. The areal extent of the onshore drainage catchments that supplied sediment to the fans has been estimated based on scaling relationships derived from modern source-to-sink systems. The results of our study suggest that the Turonian fans were sourced by drainage catchments that were up to ~3600 km2, extending more than ~100 km inland from the palaeo-shoreline. The estimated inboard catchment extent correlates to the innermost structures of a large, long-lived, basement-involved, normal fault complex. Based on our analysis we conclude that increased sediment supply to the Turonian fan systems reflects tectonic rejuvenation of the landscape, rather than eustatic sea-level or climate fluctuations. The duration of fan deposition is thus interpreted to reflect the ‘relaxation time’ of the landscape following tectonic perturbation, and fan system retrogradation and abandonment is interpreted to reflect the eventual depletion of the onshore sediment source. We demonstrate that a better understanding of the stratigraphic variability of deepwater depositional systems can be gained by taking a complete source-to-sink view of ancient sediment dispersal systems.
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Journal articleWest N, Kirby E, Bierman P, et al., 2013,
Regolith production and transport at the Susquehanna Shale Hills Critical Zone Observatory, Part 2: Insights from meteoric 10Be
, Journal of Geophysical Research: Earth Surface, Vol: 118, Pages: 1877-1896, ISSN: 2169-9011Regolith-mantled hillslopes are ubiquitous features of most temperate landscapes, and their morphology reflects the climatically, biologically, and tectonically mediated interplay between regolith production and downslope transport. Despite intensive research, few studies have quantified both of these mass fluxes in the same field site. Here we present an analysis of 87 meteoric <sup>10</sup>Be measurements from regolith and bedrock within the Susquehanna Shale Hills Critical Zone Observatory (SSHO), in central Pennsylvania. Meteoric <sup>10</sup>Be concentrations in bulk regolith samples (n=73) decrease with regolith depth. Comparison of hillslope meteoric <sup>10</sup>Be inventories with analyses of rock chip samples (n=14) from a 24 m bedrock core confirms that >80% of the total inventory is retained in the regolith. The systematic downslope increase of meteoric <sup>10</sup>Be inventories observed at SSHO is consistent with <sup>10</sup>Be accumulation in slowly creeping regolith (∼ 0.2 cm yr<sup>-1</sup>). Regolith flux inferred from meteoric <sup>10</sup>Be varies linearly with topographic gradient (determined from high-resolution light detection and ranging-based topography) along the upper portions of hillslopes at SSHO. However, regolith flux appears to depend on the product of gradient and regolith depth where regolith is thick, near the base of hillslopes. Meteoric <sup>10</sup>Be inventories at the north and south ridgetops indicate minimum regolith residence times of 10.5 ± 3.7 and 9.1 ± 2.9 ky, respectively, similar to residence times inferred from U-series isotopes in Ma et al. (2013). The combination of our results with U-series-derived regolith production rates implies that regolith production and erosion rates are similar to within a factor of two on SSHO hillcrests. ©2013. American Geophysical Union. All Rights Reserved.
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Journal articleDavison TM, O'Brien DP, Ciesla FJ, et al., 2013,
The early impact histories of meteorite parent bodies
, Meteoritics and Planetary Science, Vol: 48, Pages: 1894-1918, ISSN: 1086-9379We have developed a statistical framework that uses collisional evolution models, shock physics modeling and scaling laws to determine the range of plausible collisional histories for individual meteorite parent bodies. It is likely that those parent bodies that were not catastrophically disrupted sustained hundreds of impacts on their surfaces — compacting, heating, and mixing the outer layers; it is highly unlikely that many parent bodies escaped without any impacts processing the outer few kilometers. The first 10 - 20 Myr were the most important time for impacts, both in terms of the number of impacts and the increase of specific internal energy due to impacts. The model has been applied to evaluate the proposed impact histories of several meteorite parent bodies: up to 10 parent bodies that were not disrupted in the first 100 Myr experienced a vaporizing collision of the type necessary to produce the metal inclusions and chondrules on the CB chondrite parent; around 1 -- 5\% of bodies that were catastrophically disrupted after 12 Myr sustained impacts at times that match the heating events recorded on the IAB/winonaite parent body; more than 75\% of 100 km radius parent bodies which survived past 100 Myr without being disrupted sustained an impact that excavates to the depth required for mixing in the outer layers of the H chondrite parent body; and to protect the magnetic field on the CV chondrite parent body, the crust would have had to have been thick (~ 20 km) in order to prevent it being punctured by impacts.
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Conference paperSilva M, Foray P, Rimoy S, et al., 2013,
Influence of cyclic axial loads on the behaviour of piles driven in sand
, Paris, TC-209 Workshop, ‘Design for cyclic loading: piles and other foundations’, Publisher: Presses des Ponts, Pages: 81-84 -
Conference paperPuech A, Benzaria O, Thorel L, et al., 2013,
Cyclic stability diagrams for piles in sands
, Paris, TC-209 Workshop, ‘Design for cyclic loading: piles and other foundations’, Publisher: Presses des Ponts, Pages: 85-88 -
Conference paperAndersen KA, Puech AA, Jardine RJ, 2013,
Cyclic resistant geotechnical design and parameter selection for offshore engineering and other applications
, Paris, TC-209 Workshop, ‘Design for cyclic loading: piles and other foundations’, Publisher: Presses des Ponts, Pages: 9-44 -
Conference paperNishimura S, Jardine RJ, Fenton CH, et al., 2013,
Development of a predictive framework for geothermal and geotechnical responses in cold regions experiencing climate change
, Paris, 18th Int. Conf. on Soil Mechnics and geotechnical Engineering, Publisher: Presses des Ponts, Pages: 3391-3394
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