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81.
This work presents the project of the first stage of implementation of the integrated instrumental system of volcanic activity monitoring in Kamchatka and the Kuril Islands. The system of monitoring was designed for the purpose of ensuring public safety, aviation safety, and reducing economic losses caused by volcanic eruptions. The most active and dangerous volcanoes in Kamchatka (North and Avacha groups of volcanoes) and the Kuril Islands (volcanoes on the islands of Kunashir and Paramushir) are of first priority for monitoring. For this purpose, special observation points are planned to be installed on the volcanoes. The system of monitoring will include a complex of observations (broadband seismic station with a large dynamic range, tiltmeter, devices for gas, acoustic, and electromagnetic observations, and video camera). All the data will be passed to information processing centers in real time. New methods and algorithms of automatic and automated identification of the volcanic activity level and the probabilistic volcano hazard assessment have been developed.  相似文献   
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83.
Chronostratigraphically-justified records of regional transgressions and regressions are important for understanding the nature of the Paleocene shoreline shifts on a global scale. Review of previously synthesized data from 7 tectonically “stable” regions, namely the eastern Russian Platform, Northwestern Europe, Northwestern Africa, Northeastern Africa, the Arabian Platform, the northern Gulf of Mexico, and Southern Australia, allows a comparison of transgressions and regressions interpreted in these regions. No common patterns are found in the early Danian and late Selandian, which reflects small or zero eustatic fluctuations that are overwhelmed locally on coastlines by regional tectonic motions and local changes in dynamic support of surface topography by mantle flow. Sea level was stabilized during these stages by a warm climate and a lack of planetary-scale tectonic changes. We have detected a middle–late Danian regression that occurred in 5 of 7 study regions, and can be explained by glacial advance at ~62–63 Ma or by concurrent subduction of the Izanagi–Pacific ridge beneath eastern Asia. An early–middle Selandian transgression also occurred in 5 regions, probably, as a result of a hyperthermal at ~61 Ma that coincided with emplacement of large igneous provinces in the oceanic domain. Both events are characterized by significant diachroneity, which can also be explained by the influence of regional tectonic subsidence or uplift. Results of the present study permit us to propose a tentative framework for a new Paleocene eustatic curve that is constrained globally using available records of transgressions and regressions.  相似文献   
84.
A U-Pb (SHRIMP-II) geochronological study of rocks from the Sayzhenski, Snezhny and Nizhne-Burulzayski massifs, incorporated into the Vitim alkali province (Sayzhenski Complex) has been made. The acquired data indicate that the rocks formed in the interval of 520-486 Ma. The proximity of their age to accretionary-collision processes in the Central Asian fold belt, accompanied by intràplate magmatism, has been noted. Two independent stages in the evolution of Vitim Province magmatism are suggested: Early Paleozoic (520-485 Ma) and Late Paleozoic (350-290 Ma).  相似文献   
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86.
Based on a set of very long-living (2,000?years) Qilian junipers (Sabina przewalskii Kom.) from the north-eastern part of the Tibetan Plateau (the region of Dulan), we carefully consider the regional curve standardization (RCS) technique. For this goal, we correlate deviations of individual tree-ring width records from their regional mean age-dependent curve (RC). It turns out that these correlations keep their positivity for almost all shifts between ages compared (up to 500?years and even more) evidencing each Dulan juniper to be a unique ??thermometer??. Just the unification of these ??thermometers?? in the form RC creates a spurious positive trend in the Dulan chronology. We modify the RCS technique to closer attach RC to these ??thermometers?? in order to construct a new chronology in which the trend is absent.  相似文献   
87.
We apply a recently developed and validated numerical model of tsunami propagation and runup to study the inundation of Resurrection Bay and the town of Seward by the 1964 Alaska tsunami. Seward was hit by both tectonic and landslide-generated tsunami waves during the $M_{\rm W}$ 9.2 1964 megathrust earthquake. The earthquake triggered a series of submarine mass failures around the fjord, which resulted in landsliding of part of the coastline into the water, along with the loss of the port facilities. These submarine mass failures generated local waves in the bay within 5?min of the beginning of strong ground motion. Recent studies estimate the total volume of underwater slide material that moved in Resurrection Bay to be about 211?million m3 (Haeussler et?al. in Submarine mass movements and their consequences, pp 269?C278, 2007). The first tectonic tsunami wave arrived in Resurrection Bay about 30?min after the main shock and was about the same height as the local landslide-generated waves. Our previous numerical study, which focused only on the local landslide-generated waves in Resurrection Bay, demonstrated that they were produced by a number of different slope failures, and estimated relative contributions of different submarine slide complexes into tsunami amplitudes (Suleimani et?al. in Pure Appl Geophys 166:131?C152, 2009). This work extends the previous study by calculating tsunami inundation in Resurrection Bay caused by the combined impact of landslide-generated waves and the tectonic tsunami, and comparing the composite inundation area with observations. To simulate landslide tsunami runup in Seward, we use a viscous slide model of Jiang and LeBlond (J Phys Oceanogr 24(3):559?C572, 1994) coupled with nonlinear shallow water equations. The input data set includes a high resolution multibeam bathymetry and LIDAR topography grid of Resurrection Bay, and an initial thickness of slide material based on pre- and post-earthquake bathymetry difference maps. For simulation of tectonic tsunami runup, we derive the 1964 coseismic deformations from detailed slip distribution in the rupture area, and use them as an initial condition for propagation of the tectonic tsunami. The numerical model employs nonlinear shallow water equations formulated for depth-averaged water fluxes, and calculates a temporal position of the shoreline using a free-surface moving boundary algorithm. We find that the calculated tsunami runup in Seward caused first by local submarine landslide-generated waves, and later by a tectonic tsunami, is in good agreement with observations of the inundation zone. The analysis of inundation caused by two different tsunami sources improves our understanding of their relative contributions, and supports tsunami risk mitigation in south-central Alaska. The record of the 1964 earthquake, tsunami, and submarine landslides, combined with the high-resolution topography and bathymetry of Resurrection Bay make it an ideal location for studying tectonic tsunamis in coastal regions susceptible to underwater landslides.  相似文献   
88.
FESOM under coordinated ocean-ice reference experiment forcing   总被引:1,自引:1,他引:0  
Characteristics of the ocean state simulated with the Finite-Element Sea-Ice Ocean Model (FESOM) under the normalized year forcing of Coordinated Ocean-ice Reference Experiments (COREs; Griffies et al., Ocean Model 26:1–46, 2009) are compared with those of other models participating in COREs. In contrast to these models, FESOM is run on an unstructured mesh (with resolution varying between 20 and 150 km). It is shown that the ocean state simulated by FESOM is in most cases within the spread of other models, demonstrating that the unstructured mesh technology has reached the stage when it becomes a reliable tool for studying the large-scale ocean general circulation.  相似文献   
89.
This is a response to the Correspondence by Knight (Proceedings of the Geologists’ Association, 2011) entitled ‘Evaluating geological heritage’. In this response I suggest that geodiversity can be evaluated (1) conceptually as a natural treasure within landscape, cultural, and historical contexts and (2) numerically as a number of geosite types (not as a number of geosites). These points of view are not conflicting, but mutually profitable. Moreover, broad context and perception of geodiversity can be involved in its quantification. Geodiversity is viewed as a dynamic idea, which modifications will be reflected in every study of the regional geological heritage.  相似文献   
90.
We study the filtering and sorption parameters of laboratory-produced composite materials, such as sand-gels, sand-gels with an FeS activating additive, peat-gels, and commercial sorbents on the basis of cellulose coated with MnO2, which can be used for production of permeable geochemical barriers. The carry over and the efficiency of consumption of the active component are estimated for materials with activating additives. It is shown that all the materials under study can be used as fillers for a permeable geochemical barrier, but each of them has its own limitations.  相似文献   
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