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Ages of tide provide relevant information about the spatial distribution of existing anomalies in the normal modes of the oceans, because a delay may be associated with bottom friction energy dissipation, closely located resonances, bathymetric gradients, or radiational effects. The determination of other parameters, such as the age of diurnal tide or age of parallax, also provide further knowledge about the ocean's hydrodynamical response to acting forces. Following the development of new ocean models and the availability of a greater amount of data, these parameters can be redetermined. We present the spatial distribution of these parameters in the Northeast Atlantic Ocean and the Mediterranean Sea, obtained from 507 stations. The results are discussed in terms of bathymetric models, coastal features, sea surface temperature, wind and other environmental factors. 相似文献
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Paolo de Bernardis Martin Bucher Carlo Burigana Lucio Piccirillo 《Experimental Astronomy》2009,23(1):5-16
B-Pol is a medium-class space mission aimed at detecting the primordial gravitational waves generated during inflation through
high accuracy measurements of the Cosmic Microwave Background polarization. We discuss the scientific background, feasibility
of the experiment, and implementation developed in response to the ESA Cosmic Vision 2015-2025 Call for Proposals.
See for the full list of collaboration members and a full copy of the B-Pol proposal. 相似文献
968.
Oziel Souza de Araújo Eduardo Chemas Hindi Augustinho Rigoti Fábio Henrique Rigoti 《Geophysical Prospecting》2019,67(7):1965-1976
Geophysical investigations using conventional techniques applied to groundwater exploration can often present strong limitations involving high financial costs, complex acquisition logistics and high ambiguity in results. Dispersion of the electric current flow, induced polarization) effects, cultural noises and shallow lateral heterogeneities represent the main problems faced by geoelectric methods in these types of surveys. Moreover, elements such as intrusions and mineralization at different depths may be responsible for signal attenuation as well as high resistivity in unsaturated zones and complex three-dimensional formations or clayey zones cause variations in the electric current. The focused source electromagnetic and differentially normalized method approaches can help to solve some these issues. Aiming at a higher signal-to-noise ratio, the focused source electromagnetic method and approaches of the differentially normalized method, first applied to petroleum exploration, are tested on a groundwater target, in a karst environment sectioned by a diabase dyke. We performed the processing and analysis on real IP resistivity profiling data acquired with two-way dipole-dipole array, guided by magnetic data acquired on the same profile, mapping a diabase dyke. The inversion of focused source electromagnetic method/differentially normalized method was not performed, instead that we converted the induced polarization–resistivity data to a differential signal to qualitatively prove the presence of aquifer. Joint interpretation of focused source electromagnetic method curves and inverted two-dimensional induced polarization–resistivity sections allowed for precise delineation of a conductive zone associated with the karst aquifer, le magnetics allowed for the definition of a neighbour dyke. The techniques have great potential in the aid of groundwater exploration, contributing substantially to the reduction of interpretation ambiguity. Focused source electromagnetic method/differentially normalized method/ approaches show that a simple linear combination of the conventional geoelectric data is able to remove the geological noise and provide the vertical focusing of the electric current. 相似文献
969.
N.B. Trivedi Elesbão G. de Souza Eurico R. de Paula J.M. da Costa Hugo Fournier 《Physics of the Earth and Planetary Interiors》1981,25(3):241-244
Magnetotelluric measurements in the period range 100–86400 s were conducted at a coastal station under the equatorial electrojet (Eusebio, 3.87°S, 321.58°E). The magnetotelluric data were hand-scaled and analysed to obtain a scalar apparent resistivity profile at Eusebio. The depth of the intermediate conducting layer was found to be in the range 45–75 km and the final conducting layer seems to begin at a depth of about 350 km. Possible effects of the source field equatorial electrojet are discussed and our results are compared with those of an African station under the equatorial electrojet. 相似文献
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