Probabilistic Hazard of Tsunamis Generated by Submarine Landslides in the Cook Strait Canyon (New Zealand)     

Emily M. Lane  Joshu J. Mountjoy  William L. Power  Christof Mueller 《Pure and Applied Geophysics》2016,173(12):3757-3774

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Thermal infrared video details multiscale groundwater discharge to surface water through macropores and peat pipes          下载免费PDF全文

Martin A. Briggs  Danielle K. Hare  David F. Boutt  Glorianna Davenport  John W. Lane 《水文研究》2016,30(14):2510-2511

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A Source Model for Induced Earthquakes at the Geysers Geothermal Reservoir     

Lane R. Johnson 《Pure and Applied Geophysics》2014,171(8):1625-1640

The results of a previous study on source mechanisms of small earthquakes at the Geysers geothermal reservoir in northern California are used to investigate an extended crack model for seismic events. The seismic events are characterized by their first-degree moment tensors and interpreted in terms of a model that is a combination of a shear crack and wing cracks. Solutions to both forward and inverse problems are obtained that can be used with either dynamic or static moment tensors. The model contains failure criteria, explains isotropic parts that are commonly observed in induced earthquakes, and produces estimates of crack dimensions and maximum amount of slip. Effects of fluid pressure are easily incorporated into the model as an effective stress. The model is applied to static moment tensors of 20 earthquakes that occurred during a controlled injection project in the northwest Geysers. For earthquakes in the moment magnitude range of 0.9–2.8, the model predicts shear crack radii in the range of 10–150 m, wing crack lengths in the range of 2–25 m, and maximum slips in the range of 0.3–1.1 cm. Only limited results are obtained for the time-dependence of the earthquake process, but the model is consistent with corner frequencies of the isotropic part of the moment tensor being greater than the deviatoric part and waveforms of direct p waves that become more emergent for larger events.  相似文献   

Communicating geomorphology: global challenges for the twenty‐first century          下载免费PDF全文

Kenneth J. Gregory  Stuart N. Lane  John Lewin  Philip J. Ashworth  Peter W. Downs  Michael J. Kirkby  Heather A. Viles 《地球表面变化过程与地形》2014,39(4):476-486

The British Society for Geomorphology (BSG), established as the British Geomorphological Research Group (BGRG) in 1960, is considering how best to represent geomorphology and geomorphologists in the light of recent changes in the nature of communication. These changes provide the BSG and other academic societies with challenges and opportunities. Seven drivers of communication change are outlined: the changing position of geomorphology in higher education, the nature of academic interaction, the means of communication available, a transformation in the nature of geomorphological research, changes in funding support, the government role in resource allocation, and developments in quantifying international research impact. Challenges arising from changing communications are identified as occurring beyond the ‘academy’, in the nature of publication within the ‘academy’, and associated with meetings of the ‘academy’. Although national societies now have to contemplate significantly different purposes to provide for their members than in the twentieth century, there are opportunities available that cannot be fulfilled by international organizations alone. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

Ambiguous biogeographical patterns mask a more complete understanding of the Ordovician to Devonian evolution of Japan     

Mark Williams  Simon Wallis  Tatsuo Oji  Philip D. Lane 《Island Arc》2014,23(2):76-101

Fossil assemblages of the Ordovician to Devonian successions of Japan suggest complex temporal, environmental and geographical controls on their biogeographical signature. Thus, limited similarity at the species‐level between the trilobite, brachiopod and ostracod faunas of the South Kitakami, Hida‐Gaien and Kurosegawa terranes in part reflects the sporadic stratigraphic distribution of shelly fauna within these terranes. As a result, and with the exception of corals and pan‐tropical radiolarians, species‐level similarities are greater with other regions of East Asia and Australia than amongst the Japanese terranes. The Silurian faunas of the South Kitakami Terrane have affinities with North America, Europe, Central Asia and Australia, but there is no overriding signature to support proximity either to South China or Gondwana. Notably, brachiopod and trilobite faunas of the Middle Devonian suggest strong connections with North China. Trilobite, coral and ostracod faunas of the Hida‐Gaien Terrane show affinity, including at species level, with Siluro‐Devonian faunas from westerly‐situated palaeocontinents, especially those of Central Asian and European affinity, suggesting a continuation of the Central Asian Orogenic Belt, or of its associated lithofacies. Greater diversity of groups such as ostracods and trilobites in this terrane may signal closer links with continental shelf faunas of East Asia. The dominant biogeographical signature of the Kurosegawa Terrane is from corals and trilobites, suggesting links with the Siluro‐Devonian of Central Asia, Australia and South China. The variable biogeographic signal of the Japanese faunas may reflect the lifestyles of organisms with different physiologies and larval dispersal mechanisms, as well as the relative incompleteness of the Japanese fossil record. The present state of knowledge of the faunas cautions against placing Japan in relative proximity to the North or South China plates, or of presenting the Japanese terranes as a unified island arc to the north of the South China Plate during the Early Palaeozoic.  相似文献   

Tsunami impact assessment: development of vulnerability matrix for critical infrastructure and application to Christchurch,New Zealand     

Williams  James H.  Wilson  Thomas M.  Horspool  Nick  Lane  Emily M.  Hughes  Matthew W.  Davies  Tim  Le  Lina  Scheele  Finn 《Natural Hazards》2019,96(3):1167-1211

Natural Hazards - Tsunamis can have severe impacts on society. In addition to casualties and damage to buildings, they can also damage and disrupt critical infrastructure. To support effective risk...  相似文献   

Origin and Extent of Fresh Paleowaters on the Atlantic Continental Shelf, USA   总被引：3，自引：0，他引：3  

by Denis Cohen  Mark Person  Peng Wang  Carl W. Gable  Deborah Hutchinson  ee Marksamer  Brandon Dugan  Henk Kooi  Koos Groen  Daniel Lizarralde  Robert L. Evans  Frederick D. Day-Lewis  John W. Lane Jr. 《Ground water》2010,48(1):143-158

While the existence of relatively fresh groundwater sequestered within permeable, porous sediments beneath the Atlantic continental shelf of North and South America has been known for some time, these waters have never been assessed as a potential resource. This fresh water was likely emplaced during Pleistocene sea-level low stands when the shelf was exposed to meteoric recharge and by elevated recharge in areas overrun by the Laurentide ice sheet at high latitudes. To test this hypothesis, we present results from a high-resolution paleohydrologic model of groundwater flow, heat and solute transport, ice sheet loading, and sea level fluctuations for the continental shelf from New Jersey to Maine over the last 2 million years. Our analysis suggests that the presence of fresh to brackish water within shallow Miocene sands more than 100 km offshore of New Jersey was facilitated by discharge of submarine springs along Baltimore and Hudson Canyons where these shallow aquifers crop out. Recharge rates four times modern levels were computed for portions of New England's continental shelf that were overrun by the Laurentide ice sheet during the last glacial maximum. We estimate the volume of emplaced Pleistocene continental shelf fresh water (less than 1 ppt) to be 1300 km³ in New England. We also present estimates of continental shelf fresh water resources for the U.S. Atlantic eastern seaboard (10⁴ km³) and passive margins globally (3 × 10⁵ km³). The simulation results support the hypothesis that offshore fresh water is a potentially valuable, albeit nonrenewable resource for coastal megacities faced with growing water shortages.  相似文献   

Quantification of braided river channel change using archival digital image analysis   总被引：1，自引：0，他引：1  

S. N. Lane  P. E. Widdison  R. E. Thomas  P. J. Ashworth  J. L. Best  I. A. Lunt  G. H. Sambrook Smith  C. J. Simpson 《地球表面变化过程与地形》2010,35(8):971-985

Historical archives of grey‐scale river channel imagery are extensive. Here, we present and test a methodology to extract detailed quantitative topographic data from such imagery of sand‐bed rivers. Extracting elevation information from rivers is difficult as they are characterized by a low relative relief (<4 m); the area of interest may be spatially extensive (e.g. active channel widths >500 m in large braided rivers); the rate of change of surface elevation is generally low except in the vicinity of individual channel banks where the rate of change is very high; there is the complication that comes from inundation; and there may be an added complication caused by blockage of the field of view by vegetation. Here, we couple archival photogrammetric techniques with image processing methods and test these for quantification of sand‐bed braided river dynamics, illustrated for a 500 m wide, 3 km long reach of the South Saskatchewan River, Canada. Digital photogrammetry was used to quantify dry areas and water edge elevations. A methodology was then used to calibrate the spectral signature of inundated areas by combining established two media digital photogrammetric methods and image matching. This allowed determination of detailed depth maps for inundated areas and, when combined with dry area data, creation of complete digital elevation models. Error propagation methods were used to determine the erosion and deposition depths detectable from sequential digital elevation models. The result was a series of elevation models that demonstrate the potential for acquiring detailed and precise elevation data from any historical aerial imagery of rivers without needing associated calibration data, provided that imagery is of the necessary scale to capture the features of interest. We use these data to highlight several aspects of channel change on the South Saskatchewan River, including bar movement, bank erosion and channel infilling. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

The role of soil in vegetated gravelly river braid plains: more than just a passive response?          下载免费PDF全文

Nico Bätz  Eric P. Verrecchia  Stuart N. Lane 《地球表面变化过程与地形》2015,40(2):143-156

This paper reviews the role of alluvial soils in vegetated gravelly river braid plains. When considering decadal timescales of river evolution, we argue that it becomes vital to consider soil development as an emergent property of the developing ecosystem. Soil processes have been relatively overlooked in accounts of the interactions between braided river processes and vegetation, although soils have been observed on vegetated fluvial landforms. We hypothesize that soil development plays a major role in the transition (speed and pathway) from a fresh sediment deposit to a vegetated soil‐covered landform. Disturbance (erosion and/or deposition), vertical sediment structure (process history), vegetation succession, biological activity and water table fluctuation are seen as the main controls on early alluvial soil evolution. Erosion and deposition processes may not only act as soil disturbing agents, but also as suppliers of ecosystem resources, because of their role in delivering and changing access (e.g. through avulsion) to fluxes of water, fine sediments and organic matter. In turn, the associated initial ecosystem may influence further fluvial landform development, such as through the trapping of fine‐grained sediments (e.g. sand) by the engineering action of vegetation and the deposit stabilization by the developing aboveground and belowground biomass. This may create a strong feedback between geomorphological processes, vegetation succession and soil evolution which we summarize in a conceptual model. We illustrate this model by an example from the Allondon River (Switzerland) and identify the research questions that follow. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

Investigating the geomorphological potential of freely available and accessible structure‐from‐motion photogrammetry using a smartphone          下载免费PDF全文

Natan Micheletti  Jim H. Chandler  Stuart N. Lane 《地球表面变化过程与地形》2015,40(4):473-486

We test the acquisition of high‐resolution topographic and terrain data using hand‐held smartphone technology, where the acquired images can be processed using technology freely available to the research community. This is achieved by evaluating the quality of digital terrain models (DTM) of a river bank and an Alpine alluvial fan generated with a fully automated, free‐to‐use, structure‐from‐motion package and a smartphone integrated camera (5 megapixels) with terrestrial laser scanning (TLS) data used to provide a benchmark. To evaluate this approach a 16.2‐megapixel digital camera and an established, commercial, close‐range and semi‐automated software are also employed, and the product of the four combinations of the two types of cameras and software are compared. Results for the river bank survey demonstrate that centimetre‐precision DTMs can be achieved at close range (10 m or less), using a smartphone camera and a fully automated package. Results improve to sub‐centimetre precision with either higher‐resolution images or by applying specific post‐processing techniques to the smartphone DTMs. Application to an entire Alpine alluvial fan system shows the degradation of precision scales linearly with image scale, but that (i) the expected level of precision remains and (ii) difficulties in separating vegetation and sediment cover within the results are similar to those typically found when using other photo‐based techniques and laser scanning systems. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献