Imaging the recent sediment dynamics of the Galicia Bank region (Atlantic,NW Iberian Peninsula)     

Gemma Ercilla  David Casas  Juan T. Vázquez  Jorge Iglesias  Luís Somoza  Carmen Juan  Teresa Medialdea  Ricardo León  Ferran Estrada  Soledad García-Gil  Marcel.lí Farran  Fernando Bohoyo  Margarita García  Adolfo Maestro  ERGAP Project  Cruise Teams 《Marine Geophysical Researches》2011,32(1-2):99

Multibeam bathymetry, high resolution multi-channel, and very high resolution single-channel (3.5 kHz) seismic records were used to depict the complex geomorphology that defines the Galicia Bank region (Atlantic, NW Iberian Peninsula). This region (≈620–5,000 m water depth) is characterized by a great variety of features: structural features (scarps, highs, valleys, fold bulges), fluid dynamics-related features (structural undulations and collapse craters), mass-movement features (gullies, channels, mass-flow deposits, slope-lobe complexes, and mass-transport deposits), bottom-current features (moats, furrows, abraded surface, sediment waves, and drifts), (hemi)pelagic features, mixed features (abraded surfaces associated to mixed sediments) and bioconstructions. These features represent architectural elements of four sedimentary systems: slope apron, contouritic, current-controlled (hemi)pelagic, and (hemi)pelagic. These systems are a reflection of different sedimentary processes: downslope (mass transport, mass flows, turbidity flows), alongslope (bottom currents of Mediterranean Outflow Water, Labrador Sea Water, North Atlantic Deep Water, and Lower Deep Water), vertical settling, and the interplay between them. The architectural and sediment dynamic complexities, for their part, are conditioned by the morphostructural complexity of the region, whose structures (exposed scarps and highs) favor multiple submarine sediment sources, affect the type and evolution of the mass-movement processes, and interact with different water masses. This region and similar sedimentary environments far from the continental sediment sources, as seamounts, are ideal zones for carrying out submarine source-to-sink studies, and can represent areas subject to hazards, both geologic and oceanographic in origin.  相似文献   

Holocene palaeo-oceanography of the northern Iceland Sea,indicated by Radiolaria and sponge spicules     

Adolfo Molina-Cruz  Geomar 《第四纪科学杂志》1991,6(4):303-312

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Waiting Time Distribution of Emissions in Complex Coronal Mass Ejections     

Adolfo L. Méndez Berhondo  Ramón E. Rodríguez Taboada  Liliana Alfonso Larralde 《Astrophysics and Space Science》2006,302(1-4):213-216

The waiting time distribution of emissions in Coronal Mass Ejections (CMEs) with several emissions is examined. We define the waiting time as the time interval between the commencement of an emission and the commencement of the next emission considered as parts of a unique CME. The distribution seems to follow a power-law. Two classes of CMEs several emissions are considered: “close” and “separate” depending on angular distance between emissions.  相似文献   

Deterministic behaviour in the dynamics of solar metric radio bursts with intermediate drifting patterns     

Adolfo L. Méndez Berhondo  Ana K. Díaz Rodríguez  P. Zlobec  Lupe Cuendias Pérez 《Astrophysics and Space Science》2013,346(2):301-306

The dynamic characteristics of solar metric radio bursts with intermediate drifting patterns (fiber bursts) as they evolve at fixed frequency are examined. The data were recorded using the radio polarimeter of the Trieste Astronomical Observatory. The aim is to determine if the underlying process can be described as a deterministic chaos. Correlation dimensions and Hurst exponent are estimated showing deterministic chaotic system of low dimension.  相似文献   

Field Survey of the 2015 Chile Tsunami with Emphasis on Coastal Wetland and Conservation Areas     

Manuel Contreras-López  Patricio Winckler  Ignacio Sepúlveda  Adolfo Andaur-Álvarez  Fernanda Cortés-Molina  Camila J. Guerrero  Cyntia E. Mizobe  Felipe Igualt  Wolfgang Breuer  José F. Beyá  Hernán Vergara  Rodrigo Figueroa-Sterquel 《Pure and Applied Geophysics》2016,173(2):349-367

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The consolidation problem treated by a consistent (static) finite element approach     

Annamaria Cividini  Adolfo Zavelani Rossi 《国际地质力学数值与分析法杂志》1983,7(4):435-455

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A laboratory simulation of desalting on calcareous building stone with wet sepiolite     

Jacinta García-Talegón  Adolfo C. Iñigo  Victor Vicente-Palacios 《Environmental Earth Sciences》2016,75(10):925

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The last major earthquakes along the Magallanes–Fagnano fault system recorded by disturbed trees (Tierra del Fuego,South America)     

Antonio Pedrera  Jesús Galindo‐Zaldívar  Ana Ruiz‐Constán  Fernando Bohoyo  Pablo Torres‐Carbonell  Patricia Ruano  Adolfo Maestro  Lourdes González‐Castillo 《地学学报》2014,26(6):448-453

Forests situated above active fault zones may record hillslope evolution, thus holding information about recent seismic events. Lenga trees (Nothofagus pumilio) extend across the Magallanes–Fagnano fault system (MFFS), the active transform boundary between the South American and Scotia plates. Coseismic surface ruptures along the fault scarp tilt trees located uphill. During the interseismic period, tree growth curves the trunks. Annual tree rings from the study area show abrupt changes from concentric to asymmetric, allowing the timing of major historical earthquakes to be established. In this case, tree‐ring analysis suggests rupture on the MFFS fault scarp in 1883 ± 5 and 1941 ± 10, coinciding with the February 1, 1879 (Modified Mercalli Scale, VI) and the December 17, 1949 (Ms 7.8) earthquakes in Tierra del Fuego. Our results provide evidence that this fault system was the source of these earthquakes, which has implications for seismic hazard in the study region.  相似文献   

Analysis of an illustrative interaction between structural features and earthworm populations in Brazilian ferralsols     

Michel Brossard  Gustavo Adolfo de Freitas Fregonezi  Maria de Fátima Guimarães  Cristiane de Conti Medina  Amarildo Pasini  Lourival Vilela  Miguel Angel Ayarza 《Comptes Rendus Geoscience》2012,344(1):41-49

Ferralsols are characterized by poorly-defined horizons, weak macrostructure and strong development of a fine granular structure comprising subangular micro-aggregates. In this study, the morphological and physical modifications caused by earthworm activity in a clayey ferralsol were analysed. After describing soil structures, undisturbed samples were taken for evaluating aggregates and determining clod bulk density and particle density. Soil water retention properties were measured and an inventory of soil invertebrate macrofauna was created. The structural and porous transformations were due to aggregates created by earthworm activity. Changes in bulk density can be associated with pore modifications caused by a change in the proportions of aggregate types, and a notable reduction of total porosity was measured, tending to increase soil volume with dense aggregates. Structural modifications affected the topsoil down to 0.5 m and water retention between −1 and −33 kPa, the principal water compartment of these soils.  相似文献   

CO<Subscript>2</Subscript> emissions from a municipal site for final disposal of solid waste in Gualeguaychu,Entre Rios Province,Argentina     

Romina Sanci  Héctor O. Panarello  Héctor A. Ostera 《Environmental Earth Sciences》2012,66(2):519-528

This paper estimates CO₂ fluxes in a municipal site for final disposal of solid waste, located in Gualeguaychu, Argentina. Estimations were made using the accumulation chamber methods, which had been calibrated previously in laboratory. CO₂ fluxes ranged from 31 to 331 g m⁻² day⁻¹. Three different populations were identified: background soil gases averaging 46 g m⁻² day⁻¹, intermediate anomalous values averaging 110 g m⁻² day⁻¹ and high anomalous values averaging 270 g m⁻² day⁻¹. Gas samples to a depth of 20 cm were also taken. Gas fractions, XCO₂ < 0.1, XCH₄ < 0.01, XN₂ ~0.71 and XO₂ ~0.21, δ¹³C of CO₂ (−34 to −18‰), as well as age of waste emplacement, suggest that the study site may be at the final stage of aerobic biodegradation. In a first approach, and following the downstream direction of groundwater flow, alkalinity and δ¹³C of dissolved inorganic carbon (−15 to 4‰) were observed to increase when groundwater passed through the disposal site. This suggests that the CO₂ generated by waste biodegradation dissolves or that dissolved organic matter appears as a result of leachate degradation.  相似文献