Reference database for seismic ground-motion in Europe (RESORCE)   总被引：7，自引：5，他引：2  

S. Akkar  M. A. Sandıkkaya  M. Şenyurt  A. Azari Sisi  B. Ö. Ay  P. Traversa  J. Douglas  F. Cotton  L. Luzi  B. Hernandez  S. Godey 《Bulletin of Earthquake Engineering》2014,12(1):311-339

This paper presents the overall procedure followed in order to assemble the most recent pan-European strong-motion databank: Reference Database for Seismic Ground-Motion in Europe (RESORCE). RESORCE is one of the products of the SeIsmic Ground Motion Assessment (SIGMA; projet-sigma.com) project. RESORCE is intended to be a single integrated accelerometric databank for Europe and surrounding areas for use in the development and testing of ground-motion models and for other engineering seismology and earthquake engineering applications. RESORCE aims to contribute to the improvement of earthquake risk studies in Europe and surrounding areas. RESORCE principally updates and extends the previous pan-European strong-motion databank (Ambraseys et al. in Bollettino di Geofisica Teorica ed Applicata 45:113–129, 2004a) with recently compiled Greek, Italian, Swiss and Turkish accelerometric archives. The updates also include earthquake-specific studies published in recent years. The current content of RESORCE includes 5,882 multi-component and uniformly processed accelerograms from 1,814 events and 1,540 strong-motion stations. The moment magnitude range covered by RESORCE is $2.8 \le \hbox {M}_{\mathrm{w}} \le 7.8$ . The source-to-site distance interval extends to 587 km and distance information is given by the common point- and extended-source distance measures. The paper presents the current features of RESORCE through simple statistics that also quantify the differences in metadata and strong-motion processing with respect to the previous version of the pan-European strong-motion databank.  相似文献   

Sea Surface Salinity Observations from Space with the SMOS Satellite: A New Means to Monitor the Marine Branch of the Water Cycle     

Nicolas Reul  Severine Fournier  Jaqueline Boutin  Olga Hernandez  Christophe Maes  Bertrand Chapron  Gaël Alory  Yves Quilfen  Joseph Tenerelli  Simmon Morisset  Yann Kerr  Susanne Mecklenburg  Steven Delwart 《Surveys in Geophysics》2014,35(3):681-722

While it is well known that the ocean is one of the most important component of the climate system, with a heat capacity 1,100 times greater than the atmosphere, the ocean is also the primary reservoir for freshwater transport to the atmosphere and largest component of the global water cycle. Two new satellite sensors, the ESA Soil Moisture and Ocean Salinity (SMOS) and the NASA Aquarius SAC-D missions, are now providing the first space-borne measurements of the sea surface salinity (SSS). In this paper, we present examples demonstrating how SMOS-derived SSS data are being used to better characterize key land–ocean and atmosphere–ocean interaction processes that occur within the marine hydrological cycle. In particular, SMOS with its ocean mapping capability provides observations across the world’s largest tropical ocean fresh pool regions, and we discuss from intraseasonal to interannual precipitation impacts as well as large-scale river runoff from the Amazon–Orinoco and Congo rivers and its offshore advection. Synergistic multi-satellite analyses of these new surface salinity data sets combined with sea surface temperature, dynamical height and currents from altimetry, surface wind, ocean color, rainfall estimates, and in situ observations are shown to yield new freshwater budget insight. Finally, SSS observations from the SMOS and Aquarius/SAC-D sensors are combined to examine the response of the upper ocean to tropical cyclone passage including the potential role that a freshwater-induced upper ocean barrier layer may play in modulating surface cooling and enthalpy flux in tropical cyclone track regions.  相似文献   

Multiyear time-lapse ERT to study short- and long-term landslide hydrological dynamics     

Edouard Palis  Thomas Lebourg  Maurin Vidal  Clara Levy  Emmanuel Tric  Mickael Hernandez 《Landslides》2017,14(4):1333-1343

The geology of the “Vence” landslide (0.8 million m³, south-eastern France) explains the complex hydrology of the site which plays a key role in the destabilization of the slope (water circulation within the sliding mass, fluid exchanges between superficial layers and deep karstic aquifer through faults). To understand fluid circulations within the unstable slope, a 9.5-year multi-parametric survey was set up. The survey combines electrical resistivity tomography (daily acquisition), rainfall records since 2006 and boreholes monitoring groundwater level since 2009. The objective of this work is to present an automated clustering analysis applied to the ERT data enabled to locate geological units displaying distinct hydrogeological behaviours. Clustering analysis, based on a hierarchical ascendant classification (HAC), helped to simplify the ERT section isolating three groups of apparent resistivity values. Comparing the variations of these clusters’ behaviours in time to the variations of the groundwater levels on site, we identified hydrogeological units. The role of the faults cutting the substratum is thereby highlighted. It is the simultaneous analysis of such a large real dataset that allowed obtaining robust results characteristic of the long-term behaviour of the natural hydrogeological system. This type of qualitative information on the variability of the slope hydrogeological behaviour both spatially and temporally is crucial to help improving the conversion of resistivity data into hydrologic quantities. Indeed, the definition of petrophysical models to convert ERT measurements into hydrological measurements should be site-specific and take into account the spatial and temporal variability of the medium. In this work, we show a method that can also help to focus on the areas in depth that have different levels of permeability and observe how the saturation degree evolves in time. This can be used to optimize the location of additional instrumentation (such as temperature probes and chemical sampling) and, thus, help in the prevention of the risk in such problematic areas.  相似文献   

Co-seismic landslide detection after M 7.4 earthquake on June 23, 2020, in Oaxaca,Mexico, based on rapid mapping method using high and medium resolution synthetic aperture radar (SAR) images     

Hernandez  Norma Davila  Pastrana  Alexander Ariza  Garcia  Lizeth Caballero  de Leon  Juan Carlos Villagran  Alvarez  Antulio Zaragoza  Morales  Leobardo Dominguez  Nemiga  Xanat Antonio  Posadas  Gustavo Dominguez 《Landslides》2021,18(12):3833-3844

Landslides are the fourth most common natural disasters in the world, with Costa Rica and southern Mexico being the most affected regions of Central America (Froude and Petley, 2018). In this work, we propose a semi-automated method to detect earthquake-triggered landslides for rapid mapping after a disaster event using open Sentinel-1 data. We used high-resolution TerraSAR-X data and very high-resolution Spot-7 images to compare and evaluate the accuracy of landslide distribution maps generated from the semi-automated method, applied to the M 7.1 earthquake on June 23, 2017, in Oaxaca, Mexico. The outcomes showed better accuracy in descending orbits due to ‘windward-leeward’ physiographic conditions, with a 50.56% quality percentage. This shows a reasonably good capacity to detect co-seismic landslides. However, the breaching factor was also high because several features, such as bare soils and agricultural areas, were incorrectly identified as co-seismic landslides. Finally, this semi-automated method establishes a basis for future improvements in methodologies applied to construct rapid mapping inventories using medium SAR scales.

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Accreted fragments of the Late Cretaceous Caribbean–Colombian Plateau in Ecuador     

Marc Mamberti  Henriette Lapierre  Delphine Bosch  Etienne Jaillard  Raynald Ethien  Jean Hernandez  Mireille Polv 《Lithos》2003,66(3-4):173-199

The eastern part of the Western Cordillera of Ecuador includes fragments of an Early Cretaceous (≈123 Ma) oceanic plateau accreted around 85–80 Ma (San Juan–unit). West of this unit and in fault contact with it, another oceanic plateau sequence (Guaranda unit) is marked by the occurrence of picrites, ankaramites, basalts, dolerites and shallow level gabbros. A comparable unit is also exposed in northwestern coastal Ecuador (Pedernales unit).

Picrites have LREE-depleted patterns, high Nd_i and very low Pb isotopic ratios, suggesting that they were derived from an extremely depleted source. In contrast, the ankaramites and Mg-rich basalts are LREE-enriched and have radiogenic Pb isotopic compositions similar to the Galápagos HIMU component; their Nd_i are slightly lower than those of the picrites. Basalts, dolerites and gabbros differ from the picrites and ankaramites by flat rare earth element (REE) patterns and lower Nd; their Pb isotopic compositions are intermediate between those of the picrites and ankaramites. The ankaramites, Mg-rich basalts, and picrites differ from the lavas from the San Juan–Multitud Unit by higher Pb ratios and lower Nd_i.

The Ecuadorian and Gorgona 88–86 Ma picrites are geochemically similar. The Ecuadorian ankaramites and Mg-rich basalts share with the 92–86 Ma Mg-rich basalts of the Caribbean–Colombian Oceanic Plateau (CCOP) similar trace element and Nd and Pb isotopic chemistry. This suggests that the Pedernales and Guaranda units belong to the Late Cretaceous CCOP. The geochemical diversity of the Guaranda and Pedernales rocks illustrates the heterogeneity of the CCOP plume source and suggests a multi-stage model for the emplacement of these rocks. Stratigraphic and geological relations strongly suggest that the Guaranda unit was accreted in the late Maastrichtian (≈68–65 Ma).  相似文献   

A new look for the Southern Hemisphere jet stream     

David Gallego  Pedro Ribera  Ricardo Garcia-Herrera  Emiliano Hernandez  Luis Gimeno 《Climate Dynamics》2005,24(6):607-621

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Land cover dynamics monitoring with Landsat data in Kunming,China: a cost-effective sampling and modelling scheme using Google Earth imagery and random forests     

Ning Lu  Alexander J. Hernandez  R. Douglas Ramsey 《国际地球制图》2015,30(2):186-201

Changes in forest composition impact ecological services, and are considered important factors driving global climate change. A hybrid sampling method along with a modelling approach to map current and past land cover in Kunming, China is reported. MODIS land cover (2001–2011) data-sets were used to detect pixels with no apparent change. Around 3000 ‘no change points’ were systematically selected and sampled using Google Earth’s high-resolution imagery. Thirty-five per cent of these points were verified and used for training and validation. We used Random forests to classify multi-temporal Landsat imagery. Results show that forest cover has had a net decrease of 14385?ha (1.3% of forest area), which was primary converted to shrublands (11%), urban and barren land (2.7%) and agriculture (2.5%). Our validation indicates an overall accuracy (Kappa) of 82%. Our methodology can be used to consistently map the dynamics of land cover change in similar areas with minimum costs.  相似文献   

Hepatic histopathology in two populations of the mummichog, Fundulus heteroclitus     

W. F. Schmalz  Jr.  A. D. Hernandez  P. Weis   《Marine environmental research》2002,54(3-5)

The pollution-tolerant mummichog, Fundulus heteroclitus, inhabits a heavily contaminated estuary, Piles Creek (PC), in Linden, NJ. PC contaminants include PAHs, PCBs and many metals, including high Hg and Pb. PC mummichog livers and kidneys were compared with those from a pristine estuary in Tuckerton (TK), NJ, by standard histopathological methods, with quantification by computerized image analysis. PC livers had>2× the lipid ratios of TK livers. Cell sizes and shapes were not different between populations. TK livers had a 25% incidence of basophilic areas and an age-related 30% incidence of macrophage aggregates; PC livers had none of these lesions. PC livers had a 100% incidence of necrotic foci, compared with 55% of TK livers. Inflammation was noted in 50% of TK livers but only 27% of PC livers. Curiously, the TK livers had a 45% incidence of metacercarial cysts of a digenetic trematode, while none were found in the PC livers. The TK focal necrosis and macrophage aggregates coincided with parasite infestation. There were no observed kidney lesions in either population. Positive biomarkers in this species thus included high hepatic lipid content, possibly necrosis, but no other lesions. The lack of trematode cysts in PC livers may reflect the lack of an intermediate host in this low biodiversity estuary.  相似文献   

An early-time infrared and optical study of the Type Ia Supernova 1998bu in M96     

M. Hernandez  W. P. S. Meikle  A. Aparicio  C. R. Benn  M. R. Burleigh  A. C. Chrysostomou  A. J. L. Fernandes  T. R. Geballe  P. L. Hammersley  J. Iglesias-Paramo  D. J. James  P. A. James  S. N. Kemp  T. A. Lister  D. Martinez-Delgado  A. Oscoz  D. L. Pollacco  M. Rozas  S. J. Smartt  P. Sorensen  R. A. Swaters  J. H. Telting  W. D. Vacca  N. A. Walton  M. R. Zapatero-Osorio 《Monthly notices of the Royal Astronomical Society》2000,319(1):223-234

We present first-season infrared (IR) and optical photometry and spectroscopy of the Type Ia Supernova 1998bu in M96. We also report optical polarimetry of this event. SN 1998bu is one of the closest type Ia supernovae of modern times, and the distance of its host galaxy is well determined. We find that SN 1998bu is both photometrically and spectroscopically normal. However, the extinction to this event is unusually high, with     We find that SN 1998bu peaked at an intrinsic     Adopting a distance modulus of 30.25 (Tanvir et al.) and using Phillips et al.'s relations for the Hubble constant, we obtain     Combination of our IR photometry with those of Jha et al. provides one of the most complete early-phase IR light curves for a SN Ia published so far. In particular, SN 1998bu is the first normal SN Ia for which good pre- t _{B max} IR coverage has been obtained. It reveals that the J , H and K light curves peak about 5 days earlier than the flux in the B -band curve.  相似文献   

Using Java for distributed computing in the Gaia satellite data processing     

William O’Mullane  Xavier Luri  Paul Parsons  Uwe Lammers  John Hoar  Jose Hernandez 《Experimental Astronomy》2011,31(2-3):243-258

In recent years Java has matured to a stable easy-to-use language with the flexibility of an interpreter (for reflection etc.) but the performance and type checking of a compiled language. When we started using Java for astronomical applications around 1999 they were the first of their kind in astronomy. Now a great deal of astronomy software is written in Java as are many business applications. We discuss the current environment and trends concerning the language and present an actual example of scientific use of Java for high-performance distributed computing: ESA’s mission Gaia. The Gaia scanning satellite will perform a galactic census of about 1,000 million objects in our galaxy. The Gaia community has chosen to write its processing software in Java. We explore the manifold reasons for choosing Java for this large science collaboration. Gaia processing is numerically complex but highly distributable, some parts being embarrassingly parallel. We describe the Gaia processing architecture and its realisation in Java. We delve into the astrometric solution which is the most advanced and most complex part of the processing. The Gaia simulator is also written in Java and is the most mature code in the system. This has been successfully running since about 2005 on the supercomputer “Marenostrum” in Barcelona. We relate experiences of using Java on a large shared machine. Finally we discuss Java, including some of its problems, for scientific computing.  相似文献