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91.
Study of the glacial deposits and lacustrine sediments of Campo Felice (Apennines, central Italy) has enabled the glacial phases of the last 40 ka to be dated more precisely, and has demonstrated that the maximum glacial advance did not occur in correspondence with the last global glacial maximum and with the coldest and most arid phase suggested by the pollen, but in a period dated between about 33 and 27 ka, characterized by a less extreme climate. Furthermore, a glacial expansion took place also in the period prior to 35 ka. Correlation with the Alpine glacial variations has shown that the Apennine last glacial maximum occurred before that of the southern slope of the Alps. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
92.
对沙角A电厂主厂房(一期)进行了抗震鉴定,计算结果表明其抗震能力满足生命线工程的抗震要求,最后提出了一些抗震加固方法。  相似文献   
93.
邹从学 《华南地震》1995,15(3):95-99
介绍了地震后可能引发的地震火灾、爆炸等次生灾害;讨论了地震火灾及损失的影响因素;根据次生灾害源的分布,初步定性预测它们可能带来的损失及影响。  相似文献   
94.
根据西成矿田中泥盆统安家岔组和西汉水组具有多旋回性的特点,运用马尔科夫链分析法对其进行沉积相的划分,总结出中泥盆世处于海洋环境,并可划分为4个相带:陆缘碎屑岩相带、碳酸盐台地相带、台地边缘相带及浅海陆棚碎屑岩相带,进一步分为11个相和22个亚相。  相似文献   
95.
简要介绍了地磁台链观测在极光带电集流、赤道电集流、中低纬度大尺度电流体系、太阳风-磁层-电离层-高层大气能量耦合、高-中-低纬的扰动传输、磁层中磁流体波的传播、主磁常荚期变化等研究中的应用,综述了地磁台链观测在地磁与空间物理研究中的物理基础和研究现状,着重回顾了IMS 期间6个高纬子午台链的观测研究,总结了中国地磁台链研究的初步结果.中国所处的独特地理位置和广阔的经纬度展布提供了建立全球唯一的闭合子午圈台链的可能性.中国台链向北与俄罗斯东西伯利亚地磁台相连,一直延伸到北极光带,向南与菲律宾、印尼、澳大利亚台站相连直达南极区中山站,通过南极与对面子午线上的长城站相连,并与南美、北美台站构成一条闭合的子午圈台链.可以预料,这条台链的观测资料将为地磁与高空物理研究提供宝贵的资料,对研究日地整体行为将会有重要意义.  相似文献   
96.
四川石棉—西昌地区地震区划研究   总被引:1,自引:0,他引:1  
唐荣昌  张耀国 《地震研究》1993,16(3):306-315
本文基于对石棉—西昌地区全新世断层活动与地震活动在时间上、空间上、强度上不均匀性的认识,结合四川省近廿年来对该区地震趋势估计,采用地震危险性概率分析方法,编制了此区50年超越概率10%的地震烈度和地表基岩水平峰值加速度区划图。区划结果表明,烈度和加速度的最高值均位于冕宁以南—西昌一带,这与该段全新世地表破裂最强烈、断错地貌和古地震遗迹相对集中、强震活动频繁具有较好的一致性;区划图等烈度线和等加速度线的总体分布形态近呈南北,与断裂走向基本一致。  相似文献   
97.
98.
Increased atmospheric temperatures during the high-pressure which characterise the Mediterranean climate in the dry summer time, coupled with an increase in the intensity of storms in the following wet season over recent years, increase the risk of summer fires as well as debris flows and floods in the autumn and/or in the following years. In addition, the diffuse urbanization of Italy requires a rapid and reliable tool be available in order to obtain preliminary information, at the end of the summer season, that identifies newly fired areas that present a significant hazard to human populations. In such burned zones, soil instability may be more severe favouring debris flows which may impact on populated zones. Thus, in this paper we discuss a rapid methodology to: (i) identify burned areas using band ratio's using multitemporal LANDSAT ETM images; (ii) evaluate the potential of the burned areas as the source of debris flows based on morphometric parameters (slope and hill slope curvature); (iii) evaluate the structures, such as houses and roads, exposed to potential damage by debris flows. Hazardous areas were evaluated using a stochastical model coupled with an empirical relationship which accounts for the mobility of the debris flows. The methodology provides a classification of the most “dangerous” burned areas and the potentially maximum inundated downslope areas. This has been applied to Sicily for the period autumn 2001–autumn 2002. The total burned area was 76.37 km2. According to the classification proposed 6.4% of the burned areas were consider of very high to high hazard potential, 54.4% of medium hazard and 43.2% of low hazard potential.  相似文献   
99.
A highly active collapse sinkhole field in the evaporitic mantled karst of the Ebro river valley is studied (NE Spain). The subsidence is controlled by a NW-SE trending joint system and accelerated by the discharge of waste water from a nearby industrial state. The morphometry, spatial distribution and temporal evolution of the sinkholes have been analysed. The volume of the sinkholes yields a minimum estimate of average lowering of the surface by collapse subsidence of 46 cm. The clustering of the sinkholes and the tendency to form elongated uvalas and linear belts, in a NW–SE direction have a predictive utility and allow the establishment of criteria for a hazard zonation. With the precipitation record supplied by a pluviograph and periodic cartographic and photographic surveys the influence of heavy rainfall events on the triggering of collapses has been studied.  相似文献   
100.
On July 20, 2003, following a short duration of heavy rainfall, a debris-flow disaster occurred in the Minamata–Hougawachi area, Kumamoto Prefecture, Japan. This disaster was triggered by a landslide. In order to assess the landslide and debris-flow hazard potential of this mountainous region, the study of historic landslides is critical. The objective of the study is to couple 3D slope-stability analysis models and 2D numerical simulation of debris flow within a geographical information systems in order to identity the potential landslide-hazard area. Based on field observations, the failure mechanism of the past landslide is analyzed and the mechanical parameters for 3D slope-stability analysis are calculated from the historic landslide. Then, to locate potential new landslides, the studied area is divided into slope units. Based on 3D slope-stability analysis models and on Monte Carlo simulation, the spots of potential landslides are identified. Finally, we propose a depth-averaged 2D numerical model, in which the debris and water mixture is assumed to be a uniform continuous, incompressible, unsteady Newtonian fluid. The method accurately models the historic debris flow. According to the 2D numerical simulation, the results of the debris-flow model, including the potentially inundated areas, are analyzed, and potentially affected houses, river and road are mapped.  相似文献   
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