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831.
M. A. Ferreira F. Mota de Sá C. S. Oliveira 《Bulletin of Earthquake Engineering》2016,14(7):1957-1977
Apart from the loss of lives, injuries and homeless resulting from an earthquake, not only the economy and physical landscape are altered, but also the lives of citizens and their places of work are dramatically altered. If critical services and functions are disrupted for more than a reasonable time period, consequences can be severe. All communities are at risk and face potential disaster, if unprepared. The Disruption Index (DI) is a tool that allows the representation of a complex and multidimensional situation in a concise and easier way, providing institutions and communities with a way to identify the global earthquake impact in a geographical area, the elements at risk, and the means to reduce it. In the present paper, after a short review of the concept of DI, its geographic (spatial) distribution is developed and an application to some cities in Algarve (Portugal) is made. Then, the use of DI in the context of measuring the risk reduction for alternative disaster mitigation strategies is introduced and illustrations are presented. 相似文献
832.
Francisco Mota de Sá Mónica Amaral Ferreira Carlos Sousa Oliveira 《Bulletin of Earthquake Engineering》2016,14(7):2047-2067
Earthquakes are a permanent threat to urban environments worldwide. The communication of the related risk demands accurate damage model simulations and an interactive visualization of results. The aim of this paper is to provide a realistic problem-solving environment for earthquake discussions among decision makers, stakeholders, and the general public. QuakeIST® is an integrated earthquake simulator developed by Instituto Superior Técnico (Lisbon University), oriented towards the performance of risk calculations concerning damage propagations that use the Disruption Index concept. This software imports data stored in a GIS environment, handles different ground motion scenarios, and deals with a complex situation of different soils and vulnerabilities of various layers of civil structures (buildings, lifelines, and other urban structures). It models interdependencies between several infrastructures and between infrastructures and the urban tissue. The computer programme is very versatile, written in separate modules, allowing an experimented user to incorporate new formulations. Results can be treated with any statistical application and most common GIS commercial environments can produced their geographic visualization. Current progress and new upcoming are briefly described at the end of the paper. 相似文献
833.
The purpose of this study was to determine how vertical accretion rates in marshes vary through the millennia. Peat cores
were collected in remnant and drained marshes in the Sacramento–San Joaquin Delta of California. Cubic smooth spline regression
models were used to construct age–depth models and accretion histories for three remnant marshes. Estimated vertical accretion
rates at these sites range from 0.03 to 0.49 cm year−1. The mean contribution of organic matter to soil volume at the remnant marsh sites is generally stable (4.73% to 6.94%),
whereas the mean contribution of inorganic matter to soil volume has greater temporal variability (1.40% to 7.92%). The hydrogeomorphic
position of each marsh largely determines the inorganic content of peat. Currently, the remnant marshes are keeping pace with
sea level rise, but this balance may shift for at least one of the sites under future sea level rise scenarios. 相似文献
834.
835.
Earth science test suites to evaluate grid tools and middleware—examples for grid data access tools 总被引:1,自引:1,他引:0
W. J. Som de Cerff M. Petitdidier A. Gemünd L. Horstink H. Schwichtenberg 《Earth Science Informatics》2009,2(1-2):117-131
The Earth Science (ES) community has three major IT related concerns: Modeling (computing intensive), exploitation of datasets, and production of large shared datasets. All could be accomplishable using Grid. Different Grid middleware solutions exist and are being developed. In DEGREE (Dissemination and Exploitation of Grids in Earth sciencE) the aim was to disseminate and promote uptake of Grid in ES and to create a bridge between ES and Grid communities. DEGREE identified key ES requirements and has disseminated these to Grid projects, evaluated Grid middleware tools and standards regarding ES requirements and provided feedback to Grid developers. In order to convey requirements to the Grid community, test suite specifications were developed. Test suites provide real applications for testing functional and non-functional aspects of Grid, contrary to typical whiteboard tests or use cases. In this paper the GOMEVAL test suite is explained in detail and the results obtained are discussed. 相似文献
836.
Surface-Based 3D Modeling of Geological Structures 总被引:1,自引:0,他引:1
G. Caumon P. Collon-Drouaillet C. Le Carlier de Veslud S. Viseur J. Sausse 《Mathematical Geosciences》2009,41(8):927-945
Building a 3D geological model from field and subsurface data is a typical task in geological studies involving natural resource
evaluation and hazard assessment. However, there is quite often a gap between research papers presenting case studies or specific
innovations in 3D modeling and the objectives of a typical class in 3D structural modeling, as more and more is implemented
at universities. In this paper, we present general procedures and guidelines to effectively build a structural model made
of faults and horizons from typical sparse data. Then we describe a typical 3D structural modeling workflow based on triangulated
surfaces. Our goal is not to replace software user guides, but to provide key concepts, principles, and procedures to be applied
during geomodeling tasks, with a specific focus on quality control. 相似文献
837.
The end-Permian mass extinction devastated most marine communities and the recovery was a protracted event lasting several million years into the Early Triassic. Environmental and biological processes undoubtedly controlled patterns of recovery for marine invertebrates in the aftermath of the extinction, but are often difficult to single-out. The global diversity and distribution of marine lophophorates during the aftermath of the end-Permian mass extinction indicates that stenolaemate bryozoans, rhynchonelliform brachiopods, and lingulid brachiopods displayed distinct recovery patterns.Bryozoans were the most susceptible of the lophophorates, experiencing relatively high rates of extinction at the end of the Permian, and becoming restricted to the Boreal region during the Early Triassic. The recovery of bryozoans was also delayed until the Late Triassic and characterized by very low diversity and abundance. Following the final disappearance of Permian rhynchonelliform brachiopod survivors, Early Triassic rhynchonelliform brachiopod abundance remained suppressed despite a successful re-diversification and a global distribution, suggesting a decoupling between global taxonomic and ecological processes likely driven by lingering environmental stress.In contrast with bryozoans and rhynchonelliforms, lingulid brachiopods rebounded rapidly, colonizing shallow marine settings left vacant by the extinction. Lingulid dominance, characterized by low diversity but high numerical abundance, was short-lived and they were once again displaced back into marginal settings as environmental stress changed through the marine recovery. The presence in lingulid brachiopods of the respiratory pigment hemerythrin, known to increase the efficacy of oxygen storage and transport, when coupled with other morphological and physiological adaptations, may have given lingulids a survival advantage in environmentally stressed Early Triassic settings. 相似文献
838.
D. Van Rooij V. A. I. Huvenne D. Blamart J.-P. Henriet A. Wheeler H. de Haas 《International Journal of Earth Sciences》2009,98(4):849-863
The genesis and evolution of cold-water coral banks along the Northeastern Atlantic margin is known to be influenced by several
factors, among which the palaeotopography and nature of the coral settling surface, the presence of bottom currents and sediment
supply. In this paper, a case study is presented of the Enya mound cluster, located in the southernmost tip of the Belgica
mound province, west of Ireland. Below this mound cluster, seismic stratigraphy revealed a yet unmapped local unconformity
RD1b, being part of a composite erosion event (RD1). As such, from the Late Miocene to Late Pliocene, at least two erosional
events have incised the margin, ending with the final RD1a “moundbase” unconformity, acting as a base for the Enya mounds.
During the Quaternary the mounds became outgrown and were covered by a mounded contourite drift. In addition, they are closely
associated with a cluster of seabed pockmarks. The bottom current regime which became active since the Middle Pleistocene
has certainly influenced the fate of this mound cluster. The occurrence of the pockmarks seems to be related to relatively
recent fluid migration processes, however leaving an open question if any previous seepage phases were involved in the growth
or initiation of the coral banks. 相似文献
839.
Koen de Jong Chikao Kurimoto Gilles Ruffet 《International Journal of Earth Sciences》2009,98(6):1529-1556
The 218.4 ± 0.4, 228.8 ± 0.9 and 231.9 ± 0.7 Ma 40Ar/39Ar laser probe pseudo-plateau ages (2σ; 49–63% 39Ar-release) of very low-grade meta-pelitic whole-rocks from the Sakaigawa unit date high-P/T metamorphism. We argue that this
event occurred in a subduction–accretion complex, not along the East Asian continental margin, but on the Pacific side of
the proto-Japan superterrane. Proto-Japan was a Permian magmatic arc, presently dispersed in the Japanese islands, which also
contained older subduction–accretion complexes. The arc system was fringing but not yet part of the Eurasian continent. The
Middle to Late Triassic high-P/T tectono-metamorphic event was partly coeval with proto-Japan’s collision with proto-Eurasia
along the southward extension of the Central Asian Orogenic Belt, causing the main metamorphism in the Hida-Oki terrane. It
is possible that this system continued via the Cathaysia block (China) to Indochina. The Late Permian to Middle Triassic Indosinian
event might stem from docking of Pacific-derived terranes with Southeast Asia’s continental margin. The concept of the proto-Japan
superterrane implies that the Qinling-Dabie-Sulu suture zone joined the Central Asian Orogenic Belt to the east of the North
China craton and did not continue to Japan, as commonly assumed. 相似文献
840.
Marcelo Roberto Barbosa Mario Guimarães Buratto Leonardo Santana de Oliveira Dias João Paulo Carvalho Raivel Flavio Lobos Martins 《International journal of geographical information science》2013,27(6):873-901
To increase the monitoring potential of forest fires, an alert classification methodology using satellite-mapped hotspots has been established to help forest managers in the prioritization of which hotspot to be verified in the field, thus potentially improving the distribution of fire-fighting resources. A computer application was developed based on web-distributed geographical information technology whose main function is to interact automatically generated satellite hotspots and risk areas indicated in fire-susceptibility maps and classify them into five alert levels. The location of the hotspots is available continuously every 4 h, and a susceptibility map is produced daily through map algebra algorithm, which uses static (topography, vegetation and land use) and dynamic (weather) variables. Every process runs through automated geoprocessing routines. The methodology was tested during the dry period of 2007 in the Carajás National Forest, in the Brazilian Amazon, within an area of 400,000 ha. It is a critical area constantly threatened by fires caused by invasions and deforestation owing to intense agribusiness advances and mining activities in its surroundings. This situation results in observations of many hotspots inside the study area for the same day and almost the same time period, in places of extreme opposites, demanding complex rapid analysis and hindering the decision of the displacement of fire-fighting teams. Further, a major mining company operates within the National Forest area, maintaining actions of protection as part of its environmental mining license. Results are presented under three aspects: (i) the credibility of the daily susceptibility map (algorithm), which showed strong correlation between areas of greatest risks and the confirmed forest fires; (ii) the reliability of hotspots (alert levels), confirming 71% of fires; (iii) accuracy in the decision of which hotspot to be checked, which revealed the same number of verifications at different alert levels, 82% confirmed alert 5 hotspots (maximum) and only 50% from alert 1 (minimum), resulting in faster fire-fighting actions, minimizing burned areas and, in some cases, allowing fire control before its spreading. Therefore, the methodology demonstrated that GIS routines are able to determine the relationship between a reality-based, interpreted susceptibility map of the area and satellite-generated hotspots, highlighting the ones of highest hazard level through the alert classification, becoming an important tool to help decisions from the fire-control center, especially for high-risk regions. The methodology may be extrapolated to other forested areas. 相似文献