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31.
We explored the submarine portions of the Enriquillo–Plantain Garden Fault zone (EPGFZ) and the Septentrional–Oriente Fault zone (SOFZ) along the Northern Caribbean plate boundary using high‐resolution multibeam echo‐sounding and shallow seismic reflection. The bathymetric data shed light on poorly documented or previously unknown submarine fault zones running over 200 km between Haiti and Jamaica (EPGFZ) and 300 km between the Dominican Republic and Cuba (SOFZ). The primary plate‐boundary structures are a series of strike‐slip fault segments associated with pressure ridges, restraining bends, step overs and dogleg offsets indicating very active tectonics. Several distinct segments 50–100 km long cut across pre‐existing structures inherited from former tectonic regimes or bypass recent morphologies formed under the current strike‐slip regime. Along the most recent trace of the SOFZ, we measured a strike‐slip offset of 16.5 km, which indicates steady activity for the past ~1.8 Ma if its current GPS‐derived motion of 9.8 ± 2 mm a?1 has remained stable during the entire Quaternary.  相似文献   
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The ZoNéCo 1 and 2 cruises of Ifremer's Research Vessel L'Atalante, collected new swath bathymetry and geophysical data over the southern and northern segments of the basins and ridges forming the Loyalty system. Between the two surveyed areas, previous studies found evidence for the resistance of the Loyalty Ridge to subduction beneath the New Hebrides trench near 22°S–169°E. On the subducted plate, except for seismicity related to the downbending of the Australian plate, recorded shallow seismicity is sparse within the Loyalty system (Ridge and Basin) where reliable focal mechanism solutions are almost absent.Swath bathymetry, seismic reflection and magnetic data acquired during the ZoNéCo 1 and 2 cruises revealed a transverse asymmetric morphology in the Loyalty system, and an along-strike horst and graben structure on the discontinuous Loyalty Ridge. South of 23°50S and at 20°S, the two WSW-ENE-trending fault systems, respectively, sinistral and dextral, that crosscut the southern and northern segments of the Loyalty system, are interpreted as due to the early effects of collision with the New Hebrides Arc. A NNW-SSE trend, evident along the whole Loyalty system and on the island of New Caledonia, is interpreted as an inherited structural trend that may have been reactivated through flexure of the Australian lithospheric plate at the subduction zone.Overall then, the morphology, structure and evolution of the southern and northern segments of the Loyalty system probably result from the combined effects of the Australian plate lithospheric bulge, the active Loyalty-New Hebrides collision and the overthrust of the New Caledonian ophiolite.  相似文献   
34.
由于砾岩岩石类型复杂,储层非均质性强,难以建立地震属性与储层之间的一一对应关系,导致应用地震属性常常具有不确定性和多解性。为了克服单一属性反映粗粒沉积展布的片面性,同类属性间相关信息的彼此干扰性,地震相预测扇体分布的盲目性,针对性的提出了基于地震多属性拟合技术编制粗粒扇体沉积相图的方法:1)建立岩性识别图版;2)属性优化与线性逐步回归拟合含砂砾率;3)均方根振幅属性正态分布约束砂体边界;4)应用拟合含砂砾率等值线图,结合岩相和测井相编制粗粒扇体沉积相图。并将该方法用于玛131井区百口泉组二段的沉积研究中,为研究粗粒扇体沉积提供了新的思路,为玛湖滚动勘探及井位论证提供了可靠地质依据。  相似文献   
35.
Summary The different functions of cumulative probability of fracture that can be used in the Probabilistic Strength of Materials in the case of constant uniaxial compression are described. Sound fine-grained granite was used to study volume influence by fracturing rectangular prisms, and then no noticeable influence was observed. Since this is showing that all the fracture stresses are belonging to a single set they were included in a single group that exhibited two functions of specific risk of fracture. The population with the lesser fracture stress has no critical zone while the other population does have it and a critical zone in the order of 10–6 m3 is the minimum size exhibiting a complete fracture of the specimen when the same collapses. All the statistical functions were found to be acceptable according to theX 2 criterion.  相似文献   
36.
云计算在地震行业信息网络服务中的框架研究与设计   总被引:2,自引:0,他引:2  
云计算是当前信息网络服务技术研究的重要领域。很多机构、企业开始关注云计算,并评估自身建设云计算平台的可能性。本文通过对云计算技术发展及应用产品的研究,讨论云计算在地震行业信息网络服务中的作用和定位。结合地震行业信息网络服务应用现状,提出中国地震台网中心数据中心私有云平台的简要设计设想,为地震行业建设自有云计算服务平台提供参考模型。  相似文献   
37.
The Saclay solar evolution code is used to check the effect of WIMPs on solar evolution. In this paper we study the effects of various types of Cosmion-matter interactions, give constraints on the crosssections compatible with the measured neutrino rate of 2 SNU on chlorine, and relate these constraints to ongoing dark matter detection experiments.Unité associée au CNRS UA 280, F-75251 Paris Cedex 05, France.On leave from LPC, Collège de France.  相似文献   
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39.
Biological aerosols from air constitute a significant source of exposure to microorganisms in public places. Airborne microorganisms are involved in the development of certain respiratory symptoms, allergies, or infections among users and occupants. Various sampling instruments have commonly been used in aerobiology to collect bacteria and fungi suspended in the air. The objective of this study was to develop a reliable procedure for sampling in indoor public environments presenting different levels of occupancy, airborne bacteria and fungi to be subjected to molecular analysis (bacteria and fungi quantitative PCR, capillary electrophoresis single strand conformation polymorphism fingerprinting). Four different sampling devices were tested in situ in an office building (open‐plan type) and the sampling strategy chosen was tested in two museum contexts. In accordance with the drawbacks involved to our study (quantitative and qualitative aspects, cost, and overcrowding), cyclone device appeared to be most suitable. The results underline the effectiveness of this high‐volume aerosol sampling device for both qualitative and quantitative molecular analysis. Four in situ sampling collections were carried out in 1 day in the Louvre Museum to study quantitative and qualitative variations of airborne bacterial and fungal diversity. The quantitative results revealed a similar order of magnitude for the numbers of both bacteria and fungi. In the Louvre Museum, the samples yielded between 3.7 × 104 and 4.1 × 104 genome equivalent (GE) bacteria/m3 air and between 5.0 × 104 and 5.9 × 104 GE fungi/m3 air and in the Decorative Arts Museum between, 2.1 × 104 and 2.5 × 104 GE bacteria/m3 air and between 1.4 × 104 and 1.7 × 104 GE fungi/m3 air. The results also indicate that the dominant bacterial community displayed a stable structure over a short period of time whereas dominant eukaryotic airborne community appeared more variable.  相似文献   
40.
Résumé L'interprétation structurale des linéaments, décelés sur clichés photographiques pris par satellite, est discutée sur les bases suivantes: d'une part en pratiquant au minimum un changement d'échelle (plus grande); d'autre part en utilisant les relevés de terrain. Des exemples pris dans le Bassin Méditerranéen sédimentaire et sur le socle cristallophyllien de l'Afrique de l'Ouest permettent de définir une méthodologie commune. Ainsi en région sédimentaire, partant de prises de vue par exemple au 1/2 500 000, les échelles au 1/15 000 et au 1/50 000 se révèlent être des compléments précieux en photo-interprétation. De la même façon en zone de socle, les échelles au 1/20 000 et au 1/50 000 sont complémentaires du 1/200 000. De plus grâce aux donnés de terrain, il est possible de qualifier l'information photogéologique et d'en exprimer sa nature. Enfin les problèmes de corrélations entre rhegmatisme de socle et fracturation de couverture sont abordés de façon préliminaire: la similitude directionnelle observée devrait orienter les futures recherches en ce domaine.
The structural interpretation of disclosed lineaments on satellite's pictures ist discused on the following basis: first, with a minimum scale change (making it bigger); on the other hand using field plotting. The examples took from the Mediterranean sedimentary basin and from the western Africa crystalographic shield allow us to define a common methodology. Thus, in sedimentary area, through 1/2 500 000 scale aerial photographys, the 1/15 000 and 1/50 000 scales would be real valuable complements in photo-interpretation. Same way as, in shield zone, the 1/20 000 and 1/50 000 scales would be complements of the 1/200 000 one. More than that, because of field plotting utilisation is possible to quality photogeological information and even to explain its nature. In short correlation problems are exposed in a preliminary approach; the observed directional similitude could orientate the future research.

Zusammenfassung Die strukturelle Deutung von Lineamenten, die aus Satellitenphotos abzulesen sind, wird nach folgenden Voraussetzungen erörtert: zum einen wird zumindest eine Vergrößerung des Maßstabes vorgenommen, zum anderen werden Geländebefunde herangezogen. An Hand von Beispielen aus dem sedimentären Mittelmeerbecken sowie dem Kristallo-phyllitischen Sockel Westafrikas ist es möglich, eine gemeinsame Methodik zu definieren. So erweisen sich im sedimentären Gebiet die Maßstäbe 115 000 und 150 000 als wertvolle Ergänzungen zur Photointerpretation zum Beispiel einer Aufnahme von 12 500 000. Entsprechend ergänzen im Bereich des Sockels die Maßstäbe 120 000 und 150 000 die Aufnahme von 1200 000. Darüber hinaus ist es mit Hilfe von Geländedaten möglich, die photogeologische Information zu qualifizieren und zu beinhalten. Schließlich werden die Probleme der Korrelation zwischen Bruchbildung im Sockel und Brücken im Deckgebirge angesprochen: Die beobachtete Annäherung in der Ausrichtung soll zukünftige Untersuchungen auf diesem Gebiet orientieren.

, , : , no- , , — . . , 1: 15.000 1:50.000 12.500.000. 1: 200.000 1: 20.000 1: 50.000. . . .
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