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101.
A hydrogeological study was completed within a sub-catchment of the Zerka River drainage basin, in western Jordan. The system
is characterized by anticlinal bending with an axis trending SSW–NNE and plunging a few degrees in the SSW direction. The
anticlinal structure diverts groundwater flow towards the SSW while the strike-slipe faults cause the groundwater to diverge
where the fault is perpendicular to the groundwater flow lines, and to converge where the fault is parallel to the groundwater
flow lines. A direct relationship was found between the location of springs and the type of groundwater flow with regard to
the amount of discharge wherein large spring discharges are located in zones of converging groundwater flow lines. In areas
where faults are not abundant, the groundwater retention time in the aquifers is long and a zonation of the electrical conductivity
was detected due to mineral dissolution. By controlling groundwater flow, the anticlinal setting produces three genetic groups
of groundwater flow systems: (1) alkaline–earth alkaline water which is predominately a bicarbonate-type composition, (2)
alkaline–earth alkaline water which is predominately bicarbonate–sulfate, and (3) alkaline–earth alkaline water with a high
alkaline component. 相似文献
102.
Barbara J. Thompson Sarah E. Gibson Peter C. Schroeder David F. Webb Charles N. Arge Mario M. Bisi Giuliana de Toma Barbara A. Emery Antoinette B. Galvin Deborah A. Haber Bernard V. Jackson Elizabeth A. Jensen Robert J. Leamon Jiuhou Lei Periasamy K. Manoharan M. Leila Mays Patrick S. McIntosh Gordon J. D. Petrie Simon P. Plunkett Liying Qian Peter Riley Steven T. Suess Munetoshi Tokumaru Brian T. Welsch Thomas N. Woods 《Solar physics》2011,274(1-2):29-56
We present an overview of the data and models collected for the Whole Heliosphere Interval, an international campaign to study the three-dimensional solar?Cheliospheric?Cplanetary connected system near solar minimum. The data and models correspond to solar Carrington Rotation 2068 (20 March??C?16 April 2008) extending from below the solar photosphere, through interplanetary space, and down to Earth??s mesosphere. Nearly 200 people participated in aspects of WHI studies, analyzing and interpreting data from nearly 100 instruments and models in order to elucidate the physics of fundamental heliophysical processes. The solar and inner heliospheric data showed structure consistent with the declining phase of the solar cycle. A closely spaced cluster of low-latitude active regions was responsible for an increased level of magnetic activity, while a highly warped current sheet dominated heliospheric structure. The geospace data revealed an unusually high level of activity, driven primarily by the periodic impingement of high-speed streams. The WHI studies traced the solar activity and structure into the heliosphere and geospace, and provided new insight into the nature of the interconnected heliophysical system near solar minimum. 相似文献
103.
Marine Stewardship Council (MSC) certification is a market-based incentive program recognizing well-managed fisheries. Currently, four Argentine fisheries are involved in the MSC program. Using in-depth, semi-structured interviews with fishery stakeholders, the study surveys their perceptions regarding MSC certification. MSC certification is positively perceived because stakeholders focus on knowledge of the process. Most respondents consider certification as encouraging effective fishery stakeholders’ participation: access to information, increased communication, and reaching consensus. Market/political/social realities will prove whether a more intense participation of Argentine fisheries in the certification initiative is useful. Because some markets in the EU and USA are demanding MSC certified products, there is a need to work towards a governance structure that helps link certification with policy market outcomes to ensure exportation of Argentine fish. MSC certification may suggest improved management of participatory bottom-up planning. This bottom-up approach provides an opportunity to establish feedback mechanisms and organizational changes. 相似文献
104.
François Charlet Marc De Batist Emmanuel Chapron Sébastien Bertrand Mario Pino Roberto Urrutia 《Journal of Paleolimnology》2008,39(2):163-177
Prior to the collection of a series of sediment cores, a high- and very-high-resolution reflection seismic survey was carried
out on Lago Puyehue, Lake District, South-Central Chile. The data reveal a complex bathymetry and basin structure, with three
sub-basins separated by bathymetric ridges, bedrock islands and interconnected channels. The sedimentary infill reaches a
thickness of >200 m. It can be sub-divided into five seismic-stratigraphic units, which are interpreted as: moraine, ice-contact
or outwash deposits (Unit I), glacio-lacustrine sediments rapidly deposited in a proglacial or subglacial lake at the onset
of deglaciation (Unit II), lacustrine fan deposits fed by sediment-laden meltwater streams in a proglacial lake (Unit III),
distal deposits of fluvially derived sediment in an open, post-glacial lake (Unit IV) and authigenic lacustrine sediments,
predominantly of biogenic origin, that accumulated in an open, post-glacial lake (Unit V). This facies succession is very
similar to that observed in other glacial lakes, and minor differences are attributed to an overall higher depositional energy
and higher terrigenous input caused by the strong seismic and volcanic activity in the region combined with heavy precipitation.
A long sediment core (PU-II core) penetrates part of Unit V and its base is dated as 17,915 cal. yr. BP. Extrapolation of
average sedimentation rates yields an age of ca. 24,750 cal. yr. BP for the base of Unit V, and of ca. 28,000 cal. yr. BP
for the base of Unit IV or for the onset of open-water conditions. This is in contrast with previous glacial-history reconstructions
based on terrestrial records, which date the complete deglaciation of the basin as ca. 14,600 cal. yr. BP. This discrepancy
cannot be easily explained and highlights the need for more lacustrine records from this region.
This is the second in a series of eight papers published in this special issue dedicated to the 17,900 year multi-proxy lacustrine record of
Lago Puyehue, Chilean Lake District. The papers in this special issue were collected by M. De Batist, N. Fagel, M.-F. Loutre
and E. Chapron. 相似文献
105.
106.
Danny Arroyo Daniel García Mario Ordaz Mauricio Alexander Mora Shri Krishna Singh 《Journal of Seismology》2010,14(4):769-785
We derive strong ground-motion relations for horizontal components of pseudo-acceleration response spectra from Mexican interplate
earthquakes at rock sites (NEHRP B class) in the forearc region. The functional form is obtained from the analytical solution
of a circular finite-source model. For the regression analysis we use a recently proposed multivariate Bayesian technique.
The resulting model has similar accuracy as those models derived from regional and worldwide subduction-zone databases. However,
there are significant differences in the estimations computed from our model and other models. First, our results reveal that
attenuation in Mexico tends to be stronger than that of worldwide relations, especially for large events. Second, our model
predicts ground motions for large earthquakes at close distances to the source that are considerably larger than the estimations
of global models. Lack of data in this range makes it difficult to identify the most appropriate model for this scenario.
Nevertheless, according to the available data at the city of Acapulco, our model seems to estimate seismic hazard more adequately
than the other models. These new relations may be useful in computing seismic hazard for the Mexican forearc region, where
no similar equations had been yet proposed. 相似文献
107.
Procedures for calibration of linear models for damage limitation in design of masonry‐infilled RC frames 下载免费PDF全文
Paolo Ricci Maria Teresa De Risi Gerardo Mario Verderame Gaetano Manfredi 《地震工程与结构动力学》2016,45(8):1315-1335
Recent earthquakes have confirmed the role played by infills in the seismic response of reinforced concrete buildings. The control and limitation of damage to such nonstructural elements is a key issue in performance‐based earthquake engineering. The present work is focused on modeling and analysis of damage to infill panels, and, in particular, it is aimed towards linear analysis procedures for assessing the damage limitation limit state of infilled reinforced concrete frames. First, code provisions on infill modeling and acceptance criteria at the damage limitation limit state are reviewed. Literature contributions on damage to unreinforced masonry infill panels and corresponding displacement capacity are reported and discussed. Two procedures are then proposed aiming at a twofold goal: (i) the determination of ‘equivalent’ interstory drift ratio limits for a bare frame model and (ii) the estimation of the stiffness of equivalent struts representing infill walls in a linear model. These two quantities are determined such that a linear model ensures a reliable estimation of seismic capacity at the damage limitation limit state, providing the same intensity level as that obtained from nonlinear analyses carried out on structural models with infills. Finally, the proposed procedures are applied to four‐story and eight‐story case study‐infilled frames, designed for seismic loads according to current technical codes. The results of these application examples are presented and discussed. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
108.
109.
Hartmut H. Hellmer Monika Rhein Günther Heinemann Janna Abalichin Wafa Abouchami Oliver Baars Ulrich Cubasch Klaus Dethloff Lars Ebner Eberhard Fahrbach Martin Frank Gereon Gollan Richard J. Greatbatch Jens Grieger Vladimir M. Gryanik Micha Gryschka Judith Hauck Mario Hoppema Oliver Huhn Torsten Kanzow Boris P. Koch Gert König-Langlo Ulrike Langematz Gregor C. Leckebusch Christof Lüpkes Stephan Paul Annette Rinke Bjoern Rost Michiel Rutgers van der Loeff Michael Schröder Gunther Seckmeyer Torben Stichel Volker Strass Ralph Timmermann Scarlett Trimborn Uwe Ulbrich Celia Venchiarutti Ulrike Wacker Sascha Willmes Dieter Wolf-Gladrow 《Ocean Dynamics》2016,66(11):1379-1413
110.
Laura Carrillo Emilio Palacios-Hernández Mario Yescas Ana María Ramírez-Manguilar 《Estuaries and Coasts》2009,32(5):906-916
Salinity profiles and meteorological data were analyzed during February, May, and September 2006 in Chetumal Bay, a large,
shallow estuary of the Western Caribbean. Local meteorological conditions revealed three seasons: (1) a dry season (March–May);
(2) a wet season (June–October); and (3) the nortes season, with northerly wind events (October–February). During the nortes
and wet seasons, salinity ranged between 13 and 16 psu, and salinity was highest in the dry season, ranging between 18 and
22 psu over most of the area; a strong stratification and a significant contribution of salty water characterized this season.
Strong horizontal gradients were observed near Rio Hondo during the three seasons. Deep and narrow peculiar bathymetric features
called the pozas showed a strong stratification and a relatively high salinity. The northern part of Chetumal Bay and probably
the entire system are far from being homogeneous. 相似文献