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81.
地震前兆数据的管理与服务 总被引:7,自引:1,他引:7
简要介绍了中国地震局全国地震前兆台网中心及其前兆数据来源和特点,重点分析了该中心的数据管理、数据服务及应用。全国地震前兆台网中心在剖析地震前兆数据的结构和总结其特点的基础上,选择了自行研制的基于双表数据结构的CAPOmen平台来管理和维护各种前兆数据,并枚举了该平台所具有的一些特点,前兆台网中心还运用Web和FTP等网络传输手段与用户及研究单位进行各种数据交换和共享,提供以CAPOmen 平台为后台数据库管理的基于浏览器的前兆数据查询、浏览、下载及其他服务等。并对地震前兆数据的管理提出几点建议。 相似文献
82.
Northwestern Anatolia contains three main tectonic units: (a) the Pontide Zone in the north which consists mainly of the Gstanbul-Zonguldak Unit in the west and the BallLda<-Küre Unit in the east; (b) the Sakarya Zone (or Continent) in the south, which is juxtaposed against the Pontide Zone due to the closure of Paleo-Tethys prior to Late Jurassic time; and (c) the Armutlu-OvacLk Zone which appears to represent a tectonic mixture of both zones. These three major tectonic zones are presently bounded by the two branches of the North Anatolian Transform Fault. The two tectonic contacts follow older tectonic lineaments (the Western Pontide Fault) which formed during the development of the Armutlu-OvacLk Zone. Since the earliest Cretaceous, an overall extensional regime dominated the region. A transpressional tectonic regime of Coniacian/Santonian to Campanian age caused the welding of the Gstanbul-Zonguldak Unit to the Sakarya Zone by an oblique collision. In the Late Campanian, a transtensional tectonic regime developed, forming a new basin within the amalgamated tectonic mosaic. The different tectonic regimes in the region were caused by activity of the Western Pontide Fault. Most of the ophiolites within the Armutlu-OvacLk Zone belong to the Paleo-Tethyan and/or pre-Ordovician ophiolitic core of the Gstanbul-Zonguldak Unit. The Late Cretaceous ophiolites in the eastern parts of the Armutlu-OvacLk Zone were transported from Neo-Tethyan ophiolites farther east by left-lateral strike-slip faults along the Western Pontide Fault. There is insufficient evidence to indicate the presence of an ocean (Intra-Pontide Ocean) between the Gstanbul-Zonguldak Unit and the Sakarya Zone during Late Cretaceous time. 相似文献
83.
Jean-François Chiffoleau Dominique Auger Emmanuelle Chartier Pierre Michel Isabelle Truquet André Ficht Jean-Louis Gonzalez Louis-Alexandre Romana 《Estuaries and Coasts》2001,24(6):1029-1040
Cadmium (Cd) is among the major contaminants in the Seine estuary. In the biota, the RNO (Réseau National d’Observation, the French Mussel-Watch) has shown that Cd concentrations in mussels living at the mouth of the estuary are related to changes in inputs to this area of phosphogypsum, a calcium sulphate that is a by-product of the phosphoric acid naturally enriched with Cd. In the water column, Cd concentrations at several key estuary sites show a very marked trend toward decreased contamination in the particles as well as in the dissolved phase. The behavior of Cd in the estuary has been studied between 1991 and 1998 in the framework of the scientific program Seine-Aval. This program has highlighted punctual Cd inputs in the estuarine water column. The partition of Cd between the dissolved and the particulate phase, previously described in various estuaries, is characterized by an intense phenomenon of solubilization in the mixing zone freshwater-seawater, but the colloidal Cd fraction remains low along the whole salinity gradient, about 5% to 10% of the apparent dissolved fraction. Although the decrease of inputs induced a fall of Cd concentrations in the water column, laboratory experiments show that the estuarine particles are far from being exhausted in Cd. Despite continuous efforts to reduce the urban and industrial inputs into the estuarine and coastal waters, the Seine estuary still remains very contaminated by Cd. 相似文献
84.
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86.
Bulletin of Volcanology - Correlations on the eruptive behaviour of the volcano of Capelinhos (Fayal island) in 1957–58, with (a) solar activity, and (b) earth-tide amplitudes, by way of a... 相似文献
87.
Bulletin of Volcanology - In another paper of the author, a picture of the tectonics of the Azores was presented. The morphological analysis showed evidence of a folded and faulted structure and... 相似文献
88.
89.
The LMDZ4 general circulation model: climate performance and sensitivity to parametrized physics with emphasis on tropical convection 总被引:3,自引:11,他引:3
Frédéric Hourdin Ionela Musat Sandrine Bony Pascale Braconnot Francis Codron Jean-Louis Dufresne Laurent Fairhead Marie-Angèle Filiberti Pierre Friedlingstein Jean-Yves Grandpeix Gerhard Krinner Phu LeVan Zhao-Xin Li François Lott 《Climate Dynamics》2006,27(7-8):787-813
The LMDZ4 general circulation model is the atmospheric component of the IPSL–CM4 coupled model which has been used to perform climate change simulations for the 4th IPCC assessment report. The main aspects of the model climatology (forced by observed sea surface temperature) are documented here, as well as the major improvements with respect to the previous versions, which mainly come form the parametrization of tropical convection. A methodology is proposed to help analyse the sensitivity of the tropical Hadley–Walker circulation to the parametrization of cumulus convection and clouds. The tropical circulation is characterized using scalar potentials associated with the horizontal wind and horizontal transport of geopotential (the Laplacian of which is proportional to the total vertical momentum in the atmospheric column). The effect of parametrized physics is analysed in a regime sorted framework using the vertical velocity at 500 hPa as a proxy for large scale vertical motion. Compared to Tiedtke’s convection scheme, used in previous versions, the Emanuel’s scheme improves the representation of the Hadley–Walker circulation, with a relatively stronger and deeper large scale vertical ascent over tropical continents, and suppresses the marked patterns of concentrated rainfall over oceans. Thanks to the regime sorted analyses, these differences are attributed to intrinsic differences in the vertical distribution of convective heating, and to the lack of self-inhibition by precipitating downdraughts in Tiedtke’s parametrization. Both the convection and cloud schemes are shown to control the relative importance of large scale convection over land and ocean, an important point for the behaviour of the coupled model. 相似文献
90.
Trace Metal Solid State Speciation in Aerosols of the Northern Levantine Basin,East Mediterranean 总被引:3,自引:0,他引:3
Mustafa Koçak Nilgun Kubilay Barak Herut Malcolm Nimmo 《Journal of Atmospheric Chemistry》2007,56(3):239-257
An established three stage sequential leach scheme was applied to a series of selected high volume aerosol samples (n = 35) collected from the Turkish Eastern Mediterranean coastline (Erdemli). Samples were selected according to their air
mass back trajectory history to reflect the contrasting mixtures of aerosol material present in the Eastern Mediterranean
marine aerosol. Two populations were adopted, those samples which were classed as “anthropogenic” and those which were “Saharan”
dominated aerosol populations. Applying the three stage leach it was possible to define the proportion for each of the considered
metals (Al, Fe, Cu, Pb, Cd, Zn and Mn) present in the (a) “exchangeable” (b) “carbonate / oxide” and (c) “refractory” phases,
representing novel solid state aerosol speciation data for this marine system. Clear trends were established, conforming with
data from previous studies with mainly crustal derived metals (Al and Fe) being present in the refractory phases (Al > 88%;
Fe > 84%) and those influenced by anthropogenic sources being dominating in the exchangeable phase, although for these metals
the variability was comparatively high (12–64%; 19–85%; 40–100% for Zn, Pb and Cd, respectively). For the majority, greater
exchangeable fractions were present the lower the crustal source contribution to the aerosol population, whereas the “refractory”
fraction exhibited contrasting behaviour. This was illustrated by the novel application of the mixing diagram, presenting
each of the three speciation stages against the corresponding percent anthropogenic contribution to each collected sample.
Zn, Pb and Cd all illustrated progressive decrease in the percent exchangeable with increasing crustal contribution to the
aerosol population. The percent exchangeable was discussed in terms of its use to represent the upper limit of the bioavailable
fraction of metal associated with the aerosol, post deposition. The mixing diagram approach enabled the prediction of the
residual fractions for Cd, Pb and Zn (41 ± 4%; 62 ± 4% and 82 ± 5%, respectively,) in Saharan end-member material. 相似文献