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11.
Andre Guillaume 《Tectonophysics》1978,48(1-2)
This work discusses the state of knowledge (mainly tectonic and geophysical data) about the Tonale line and other “peri-Adriatic” lines in the Central and Eastern Alps. The chain is here cut into a mosaic of independent blocs, separated by faults with basic injections in some places. The Tonale fault had a dextral movement in Oligo-Miocene times; it is connected with the Austrian “Thermenlinie”, and not to the Pusteria—Gail line. An attempt at chronology is presented.
Résumé
Ce travail fait le point des connassiances, principalement tectoniques et géophysiques, sur la linge du Tonale et les accidents “péri-adriatiques” récents des Alpes centrales et Orientales. Dans cette région, la chaine est découpée en une mosaïque de blocs indépendants, séparés par des accidents injectés ça et là de masses basiques. L'accident du Tonale, Qui a joué en décrochement dextre à l'Oligo-Miocéne, est relié à la Thermenlinie d'Autriche Et non à la linge Pusteria—Gail. Un essai de chronologie est présenté. 相似文献12.
C. Hans Nelson Andres Maldonado Francis Coumes Henri Got Andre Manaco 《Geo-Marine Letters》1984,3(2-4):125-131
The Ebro Fan System consists of en echelon channel-levee complexes, 50×20 km in area and 200-m thick. A few strong reflectors
in a generally transparent seismic facies identify the sand-rich channel floors and levee crests. Numerous continuous acoustic
reflectors characterize overbank turbidites and hemipelagites that blanket abandoned channel-levee complexes. The interlobe
areas between channel complexes fill with homogeneous mud and sand from mass flow and overbank deposition; these exhibit a
transparent seismic character. The steep continental rise and sediment “drainage” of Valencia Trough at the end of the channel-levee
complexes prevent the development of distributary channels and midfan lobe deposits.
Margin setting represents fan and/or source area 相似文献
13.
Although not well understood scientifically, integrated and diversified aquaculture-agriculture systems have a history of some two millennia in parts of South and Southeast Asia. With the extremely limited farm area and scanty resources available to the typical small-scale farmer of these regions, integrated agro-ecosystems, based on generations of empirical knowledge, provide a balanced diet and often a small marketable surplus for poor rural households, while continuously recycling nutrients and energy through the system, producing little waste, and maintaining a local ecological balance. Despite the few scientific data available on such systems, they are being widely advocated for use in developing countries with no prior experience of integrated farming.This paper (paper I) describes the environmental context and provides an overview of the mulberry dike-polycultural carp pond resource system of Leliu Commune, in the Zhujiang Delta of the People's Republic of China, where complex and highly productive integrated farming systems are operated on a geographical and economic scale unmatched elsewhere. Subsequent papers will focus on the human ecology of the dike-pond system, the ecological basis for system integration, and the results and implications of experiments and trials for increasing the productivity of and the economic rate of return from the system. 相似文献
14.
E.C. Sittler Jr. N. Andre M. Burger A. Coates D. Reisenfeld A. Persoon H.T. Smith R.E. Hartle M.D. Shappirio D.J. McComas 《Planetary and Space Science》2008,56(1):3-18
Using ion-electron fluid parameters derived from Cassini Plasma Spectrometer (CAPS) observations within Saturn's inner magnetosphere as presented in Sittler et al. [2006a. Cassini observations of Saturn's inner plasmasphere: Saturn orbit insertion results. Planet. Space Sci., 54, 1197-1210], one can estimate the ion total flux tube content, NIONL2, for protons, H+, and water group ions, W+, as a function of radial distance or dipole L shell. In Sittler et al. [2005. Preliminary results on Saturn's inner plasmasphere as observed by Cassini: comparison with Voyager. Geophys. Res. Lett. 32(14), L14S04), it was shown that protons and water group ions dominated the plasmasphere composition. Using the ion-electron fluid parameters as boundary condition for each L shell traversed by the Cassini spacecraft, we self-consistently solve for the ambipolar electric field and the ion distribution along each of those field lines. Temperature anisotropies from Voyager plasma observations are used with (T⊥/T∥)W+∼5 and (T⊥/T∥)H+∼2. The radio and plasma wave science (RPWS) electron density observations from previous publications are used to indirectly confirm usage of the above temperature anisotropies for water group ions and protons. In the case of electrons we assume they are isotropic due to their short scattering time scales. When the above is done, our calculation show NIONL2 for H+ and W+ peaking near Dione's L shell with values similar to that found from Voyager plasma observations. We are able to show that water molecules are the dominant source of ions within Saturn's inner magnetosphere. We estimate the ion production rate SION∼1027 ions/s as function of dipole L using NH+, NW+ and the time scale for ion loss due to radial transport τD and ion-electron recombination τREC. The ion production shows localized peaks near the L shells of Tethys, Dione and Rhea, but not Enceladus. We then estimate the neutral production rate, SW, from our ion production rate, SION, and the time scale for loss of neutrals by ionization, τION, and charge exchange, τCH. The estimated source rate for water molecules shows a pronounced peak near Enceladus’ L shell L∼4, with a value SW∼2×1028 mol/s. 相似文献
15.
Scale Matching with Factorial Kriging for Improved Porosity Estimation from Seismic Data 总被引:1,自引:0,他引:1
When seismic data and porosity well logs contain information at different spatial scales, it is important to do a scale-matching of the datasets. Combining different data types with scale mismatch can lead to suboptimal results. A good correlation between seismic velocity and rock properties provides a basis for integrating seismic data in the estimation of petrophysical properties. Three-dimensional seismic data provides an unique exhaustive coverage of the interwell reservoir region not available from well data. However, because of the limitations of measurement frequency bandwidth and view angles, the seismic image can not capture the true seismic velocity at all spatial scales present in the earth. The small-scale spatial structure of heterogeneities may be absent in the measured seismic data. In order to take best advantage of the seismic data, factorial kriging is applied to separate the small and large-scale structures of both porosity and seismic data. Then the spatial structures in seismic data which are poorly correlated with porosity are filtered out prior to integrating seismic data into porosity estimation. 相似文献
16.
Influence of earthquake ground‐motion duration on damage estimation: application to steel moment resisting frames
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This paper presents an analytical study evaluating the influence of ground motion duration on structural damage of 3‐story, 9‐story, and 20‐story SAC steel moment resisting frame buildings designed for downtown Seattle, WA, USA, using pre‐Northridge codes. Two‐dimensional nonlinear finite element models of the buildings are used to estimate the damage induced by the ground motions. A set of 44 ground motions is used to study the combined effect of spectral acceleration and ground motion significant duration on drift and damage measures. In addition, 10 spectrally equivalent short‐duration shallow crustal ground motions and long‐duration subduction zone records are selected to isolate duration effect and assess its effect on the response. For each ground motion pair, incremental dynamic analyses are performed at at least 20 intensity levels and response measures such as peak interstory drift ratio and energy dissipated are tracked. These response measures are combined into two damage metrics that account for the ductility and energy dissipation. Results indicate that the duration of the ground motion influences, above all, the combined damage measures, although some effect on drift‐based response measures is also observed for larger levels of drift. These results indicate that because the current assessment methodologies do not capture the effects of ground motion duration, both performance‐based and code‐based assessment methodologies should be revised to consider damage measures that are sensitive to duration. Copyright © 2016 John Wiley & Sons, Ltd 相似文献
17.
Leonardo de Magalhães Natália Pessoa Noyma Luciana Lima Furtado Maíra Mucci Frank van Oosterhout Vera L. M. Huszar Marcelo Manzi Marinho Miquel Lürling 《Estuaries and Coasts》2017,40(1):121-133
Eutrophication is considered the most important water quality problem in freshwaters and coastal waters worldwide promoting frequent occurrence of blooms of potentially toxic cyanobacteria. Removal of cyanobacteria from the water column using a combination of coagulant and ballast is a promising technique for mitigation and an alternative to the use of algaecides. In laboratory, we tested experimentally the efficiency of two coagulants, polyaluminium chloride (PAC) and chitosan (made of shrimp shells), alone and combined with two ballasts: red soil (RS) and the own lagoon sediment, to remove natural populations of cyanobacteria, from an urban brackish coastal lagoon. PAC was a very effective coagulant when applied at low doses (≤8 mg Al L?1) and settled the cyanobacteria, while at high doses (≥16 mg Al L?1) large flocks aggregated in the top of test tubes. In contrast, chitosan was not able to form flocks, even in high doses (>16 mg L?1) and did not efficiently settle down cyanobacteria when combined with ballast. The RS itself removed 33–47 % of the cyanobacteria. This removal was strongly enhanced when combined with PAC in a dose-dependent matter; 8 mg Al L?1 was considered the best dose to be applied. The lagoon sediment alone did not promote any settling of cyanobacteria but removal was high when combined with PAC. Combined coagulant and ballast seems a very efficient, cheap, fast and safe curative measure to lessen the harmful cyanobacteria bloom nuisance in periods when particularly needed, such as around the 2016 Olympics in Jacarepaguá Lagoon. 相似文献
18.
Eman Al-Awadi Michael Quinn Amitabha Mukhopadhyay Andre Hauser Adnan Akber Adel Al-Haddad Majed Al-Rashedi 《Environmental Geology》2009,56(5):877-889
A study, aimed at characterizing the nature of anthropogenic and biogenic hydrocarbon contamination in the groundwater of
Kuwait, was carried out using fluorescence spectroscopy and other analytical techniques. The results of these analyses have
demonstrated that the groundwater in certain areas of northern Kuwait has been significantly impacted by contamination originating
from the oil-contaminated surface soils. The study revealed that a water-soluble fraction (WSF) of the crude oil surface contamination
appeared to be slowly leaching into the freshwater lenses located in the area. The study also showed that hydrocarbon pollutants
were practically absent in the brackish water areas of central and southern Kuwait, except for a few isolated sites. However,
nonpetroleum hydrocarbons, with ultraviolet-visible absorption characteristics and fluorescence characteristics typically
associated with humic substances, were observed at a few sites in the brackish water fields. 相似文献
19.
Abstract On the basis of the Atterberg indexes of various sediments collected in the Mediterranean Sea, we select two major parameters indicative of the mechanical behavior of marine soils: the sedimentary facies (i.e., mechanism of deposition expressed by silt content) and the clay mineral association characterized by smectite content in the fraction finer than 2 μm. Activity and real thixotropic ability appear to be particularly important parameters in marine engineering; better values are obtained by a double test operation in distilled and marine water. 相似文献
20.
The small, genetically distinct population of Indo-Pacific bottlenose dolphins (Tursiops aduncus) in Port Stephens, New South Wales (NSW), is the target of the largest dolphin-watching industry in Australia and falls within the recently created Port Stephens—Great Lakes Marine Park. The effectiveness of Speed Restriction Zones (SRZs) as a management tool in this area was investigated during their second year of implementation by comparing dolphin usage and behaviour to adjacent Control Zones (CZs) of similar habitat. For this purpose, boat-based surveys and focal follows of dolphin groups were carried out in the zones between August 2008 and August 2009. Results showed that SRZs were more intensely used by dolphin-watching boats in summer. There was no change in dolphins’ behaviour and group structure in the presence of dolphin-watching boats in SRZs when compared to dolphin groups within CZs in any season. Dolphin groups including calves used SRZs less during summer. The latter may indicate a shift in area utilisation for those groups during intense boat traffic by dolphin-watching operators. CZs were more important than SRZs as foraging grounds for dolphins in summer. This indicates that SRZs as specified are not effective at minimising boating impacts and that the location of these zones should in time be revised. This is important information for management of dolphin-watching within this marine park and an example of adaptive management in progress. Moreover these results are relevant for conservation of dolphins and the management of dolphin-watching industries elsewhere, particularly new industries, where management strategies may incorporate marine protected areas including zoning plans. 相似文献