Announcement     

D. A. Novelo-Casanova  Gerardo Suárez 《Natural Hazards》1988,1(1):111-112

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Book reviews     

Yukio Fujinawa  A. V. Koloskov  Gerardo G. Tango  Lech Stefaníak  Douglas R. Schmitt  Kei Katsumata  Vernon F. Cormier  Wladislaw Lyatsky  Krzysztof Haman  P. Vincent  Konrad Bajer  Henryk Piwkowski 《Pure and Applied Geophysics》1991,136(2-3):343-367

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The relative locations of multiplets in the vicinity of the Western Almería (southern Spain) earthquake series of 1993–1994     

Daniel Stich  Gerardo Alguacil  José Morales 《Geophysical Journal International》2001,146(3):801-812

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Importance of grid-cell area in the estimation of estuarine residual fluxes   总被引：1，自引：0，他引：1  

Gerardo M. E. Perillo  M. Cintia Piccolo 《Estuaries and Coasts》1998,21(1):14-28

Estimation of residual fluxes in estuarine cross sections is a very important procedure to establish, among others aspects, residence time of contaminants, circulation pattern, and sediment transport dynamics. However, the analytical procedure to obtain such values is not trivial and is presented in detail, demonstrating the importance of the grid-cell area as a weighting element in the calculation of spatial averages. The procedure is tested with four different grid designs and it is shown that grids with proportional columns and rows are the only ones that do not introduce statistical noise in the estimation of the residual fluxes. The four designs are also tested with data from a cross section of the Bahía Blanca Estuary (Argentina), results again show that the proportional columns and rows grid provide the best approach in calculating residual fluxes.  相似文献   

Medium-term responses of rocky bottoms to sewage discharges from a deepwater outfall in the NE Atlantic     

Echavarri-Erasun B  Juanes JA  García-Castrillo G  Revilla JA 《Marine pollution bulletin》2007,54(7):941-954

An investigation on the effects of deepwater outfall discharges on the status of rocky reef communities was carried out. The sanitation system was found to be an environmentally suitable option for the protection of those habitats situated in high energy coastal environments. Sediments occurring between the predominating rocky substrates showed low values of the fine fraction (<63microm) and organic matter content. In addition, high average concentrations of Cd, Hg and Zn were found in these sediments, though these values were similar to those registered in non-affected sites, far away from the outfall. On the other hand, those assemblages typical of hard substrates that settled near the outfall showed an increase in total richness and abundance of macroinvertebrates. Moreover, the average number of species of each taxonomic group, a good indicator of the maintenance of the previous trophic structure, only varied considerably over time at the rip-rap protection. In a global context, those changes were not directly related to the discharge disturbances, but to the natural variability or the successional processes occurring within those communities. Only communities dwelling in the rip-rap protection area were affected by the proximity of the discharges.  相似文献   

Venomous snakes and climate change: ophidism as a dynamic problem     

Javier Nori  Paola A. Carrasco  Gerardo C. Leynaud 《Climatic change》2014,122(1-2):67-80

Snakebite envenoming is an important public health problem worldwide and addressing this issue has turned into a challenge for applied science. In this sense, the study of the distributional patterns of problematic snakes is central in terms of public health. Global Climate Change is affecting the distributional ranges of snakes, so that decisions regarding treatment of ophidism (poisoning by snake venom) may also change spatially and/or temporally. Here, we assessed suitable climate spaces at present conditions and estimated potential future changes in the distributions of the five southernmost venomous snakes, responsible for almost 99 % of accidents in Argentina, by implementing an ensemble of forecasts between different algorithms and scenarios for 2030 and 2080. Present suitable climate spaces showed high concordance with known distribution of the species. Future projections show moderate “north to south” displacements of the snakes’ suitable climate spaces, implying potential increments of suitable spaces in human populated areas in Argentina. Our results suggest the necessity of considering ophidism as a dynamic problem. In this regard, the analyses implemented here are useful tools in improving the assessment of snakebite envenoming in light of global climate change.  相似文献   

X-rays from the Symbiotic Star RX Pup     

Gerardo J. M. Luna  J. L. Sokoloski  Roberto D. D. Costa 《Astrophysics and Space Science》2006,304(1-4):283-285

We describe X-ray and optical observations of the symbiotic star RX Pup. From low resolution optical spectra, we obtain a reddening for RX Pup of E(B−V)=0.79. We use the neutral column density corresponding to this reddening as a lower limit for the X-ray spectra fits. The X-ray spectra can be fitted with either a two-temperarure thermal plasma model or a single-temperature plasma plus a narrow line at ≈0.55 keV, each modified by interstellar absorption. The RX Pup X-ray flux is not variable within the observation exposure time, suggesting that unlike in most CVs, an accretion disk boundary layer does not contribute significantly to the X-ray flux. Instead, the X-ray emission may come from shock-heated gas further away from the compact object.  相似文献   

Flood-prone areas assessment using linear binary classifiers based on flood maps obtained from 1D and 2D hydraulic models   总被引：3，自引：0，他引：3  

Salvatore Manfreda  Caterina Samela  Andrea Gioia  Giuseppe Gerardo Consoli  Vito Iacobellis  Luciana Giuzio  Andrea Cantisani  Aurelia Sole 《Natural Hazards》2015,79(2):735-754

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Evolution of a complex isolated dome system,Cerro Pizarro,central México     

Nancy?RiggsEmail author  Gerardo?Carrasco-Nunez 《Bulletin of Volcanology》2004,66(4):322-335

Cerro Pizarro is an isolated rhyolitic dome in the intermontane Serdán-Oriental basin, located in the eastern Trans-Mexican Volcanic Belt. Cerro Pizarro erupted ~1.1 km³ of magma at about 220 ka. Activity of Cerro Pizarro started with vent-clearing explosions at some depth; the resultant deposits contain clasts of local basement rocks, including Cretaceous limestone, ~0.46-Ma welded tuff, and basaltic lava. Subsequent explosive eruptions during earliest dome growth produced an alternating sequence of surge and fallout layers from an inferred small dome. As the dome grew both vertically and laterally, it developed an external glassy carapace due to rapid chilling. Instability of the dome during emplacement caused the partial gravitational collapse of its flanks producing various block-and-ash-flow deposits. After a brief period of repose, re-injection of magma caused formation of a cryptodome with pronounced deformation of the vitrophyric dome and the underlying units to orientations as steep as near vertical. This stage began apparently as a gas-poor eruption and no explosive phases accompanied the emplacement of the cryptodome. Soon after emplacement of the cryptodome, however, the western flank of the edifice catastrophically collapsed, causing a debris avalanche. A hiatus in eruptive activity was marked by erosion of the cone and emplacement of ignimbrite derived from a caldera to the north of Cerro Pizarro. The final growth of the dome growth produced its present shape; this growth was accompanied by multiple eruptions producing surge and fallout deposits that mantle the topography around Cerro Pizarro. The evolution of the Cerro Pizarro dome holds aspects in common with classic dome models and with larger stratovolcano systems. We suggest that models that predict a simple evolution for domes fail to account for possibilities in evolutionary paths. Specifically, the formation of a cryptodome in the early stages of dome formation may be far more common than generally recognized. Likewise, sector collapse of a dome, although apparently rare, is a potential hazard that must be recognized and for which planning must be done.Editorial responsibility: J. Gilbert  相似文献   

Pyroclastic Flow Hazard at Volcán Citlaltépetl     

Sheridan  Michael F.  Hubbard  Bernard  Carrasco-núñez  Gerardo  Siebe  Claus 《Natural Hazards》2004,33(2):209-221

Volcán Citlaltépetl (Pico de Orizaba) with an elevation of 5,675 m is the highest volcano in North America. Its most recent catastrophic events involved the production of pyroclastic flows that erupted approximately 4,000, 8,500, and 13,000 years ago. The distribution of mapped deposits from these eruptions gives an approximate guide to the extent of products from potential future eruptions. Because the topography of this volcano is constantly changing computer simulations were made on the present topography using three computer algorithms: energy cone, FLOW2D, and FLOW3D. The Heim Coefficient (), used as a code parameter for frictional sliding in all our algorithms, is the ratio of the assumed drop in elevation (H) divided by the lateral extent of the mapped deposits (L). The viscosity parameter for the FLOW2D and FLOW3D codes was adjusted so that the paths of the flows mimicked those inferred from the mapped deposits. We modeled two categories of pyroclastic flows modeled for the level I and level II events. Level I pyroclastic flows correspond to small but more frequent block-and-ash flows that remain on the main cone. Level II flows correspond to more widespread flows from catastrophic eruptions with an approximate 4,000-year repose period. We developed hazard maps from simulations based on a National Imagery and Mapping Agency (NIMA) DTED-1 DEM with a 90 m grid and a vertical accuracy of ±30 m. Because realistic visualization is an important aid to understanding the risks related to volcanic hazards we present the DEM as modeled by FLOW3D. The model shows that the pyroclastic flows extend for much greater distances to the east of the volcano summit where the topographic relief is nearly 4,300 m. This study was used to plot hazard zones for pyroclastic flows in the official hazard map that was published recently.  相似文献