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651.
位于焦家断裂带的新城金矿床矿体主要赋存于主裂面(断层泥)下盘的黄铁绢英岩化碎裂岩带和黄铁绢英岩化花岗闪长质碎裂岩带内。根据勘探资料和测试数据对矿床内Ⅰ号和Ⅴ号主要矿体的赋存特征进行分析, 并结合矿区水文和环境特点对矿床进行了开采评价。研究结果表明, 新城金矿区工程地质条件简单; 矿床开采形成的采空区对矿区岩体稳定性产生的影响较小, 研究区内的主矿体为地质环境条件良好型矿体。   相似文献   
652.
20世纪以来,川滇地区M≥6.7强震时间间隔具有良好的规律性,其地震发生的年份可组成一个二维时间坐标系,并据此建立川滇地区的强震时间预测模型。预测分析表明:未来16年,川滇地区可能存在发生4次6.7级以上地震发生的风险,2012-2021及2025-2029年均有M≥6.7强震信号,且未来强震可能发生在2014-2015、2019与2027年前后。  相似文献   
653.
The newly discovered Jiaojiguan deposit, a medium-scale skarn iron-tin polymetallic deposit on the Sino-Burma boundary of Yunnan Province (SW China), is spatially associated with the biotite monzonitic granite. Here, we report new in situ zircon LA-MC-ICP-MS U–Pb ages, trace element and Hf isotope data from the granite, and U–Pb dating ages of cassiterite from the ore bodies. In this study, we obtain a weighted mean 206Pb/238U age of 124.1 ± 1.4 Ma for the zircon and a 207Pb/206Pb-238U/206Pb intercept age of 123.8 ± 2.2 Ma for the cassiterite. The granite crystallized during the Early Cretaceous, with zircons exhibiting εHf(t) values from ?5.8 to ?0.6 and two-stage Hf model ages (TDM2) of 1.21–1.54 Ga. The close temporal and spatial links between pluton emplacement and ore-forming events suggest that magmatic-hydrothermal events were the key factors that triggered the genesis of the iron-tin polymetallic deposits in the area. Regional geochronological data show that tin mineralization took place three times during the Cretaceous–Palaeogene in the Tengchong block due to re-melting of the underlying supposed Proterozoic (1.5 ± 0.5 Ga) Sn-rich strata/materials. Compared with those in the Bangong–Nujiang metallogenic belt (BNMB), we propose that the Cretaceous iron-tin polymetallic mineralization events in Tengchong–Baoshan closely resemble those of the Bangong–Nujiang belt in northern Tibet, both of which have experienced similar tectono-magmatic-metallogenic histories since the Mesozoic.  相似文献   
654.
张春 《地质与勘探》2017,53(3):599-608
随着勘探开发的深入,对四川盆地磨溪龙王庙组气藏流体分布的认识发生变化,由早期的无水气藏或无边底水气藏转变为存在边底水、局部封存水,表现出复杂的气水关系,这制约了气藏的高效开发。为此,本次研究综合现有录井、岩心、测井、地震、测试及生产资料,识别出溶蚀孔洞发育区,在此基础上,采用印模法恢复研究区龙王庙组古地貌格局,结合现今构造特征,综合分析认为:(1)油气分布既受现今构造圈闭控制,又受有利岩相控制,也受古地貌影响;(2)古地貌控制了早期油气聚集,在地势较高的缓坡区聚集油气,在局部洼陷区滞留地层水,在地势变陡的低部位形成富水区;(3)在现今构造圈闭范围内,由于物性、闭合度和海拔高差存在差异,导致东、西部井区含气性不同,西区富气程度优于东区;(4)结合古今构造格局,在古地貌地势低部位(地势低于-300m)、现今构造低部位(海拔低于-4385m)广泛分布边水;(5)当古地貌地势低于-300m时,在现今构造和古地貌相对凸起部位存在局部油气聚集。  相似文献   
655.
Probability-based assessment of hurricane damage costs for coastal communities is vital for policy-makers and insurers. The uncertainties associated with hurricane damage costs include both the inherent uncertainty due to the random nature of hurricane process and the model uncertainty of the mathematical representation of hurricane damage (vulnerability model). The hurricane vulnerability model has traditionally been modeled as a deterministic function of hurricane wind speed in the literature, without considering the effect of vulnerability model uncertainty on hurricane damage assessment. This paper develops two methods to assess the hurricane damage costs in the presence of vulnerability model uncertainty. To account for the non-stationarity in hurricane actions due to the potential impact of climate change, the hurricane occurrence process is modeled as a non-stationary Poisson process and the hurricane intensity is assumed to vary in time with time-variant statistical parameters of hurricane wind speed. A case study of Miami-Dade County, Florida, is conducted to illustrate the proposed methods and to investigate the impact of vulnerability model uncertainty on hurricane damage costs.  相似文献   
656.
Tang  ShiYang  Shu  XueMing  Shen  ShiFei  Li  ZhangHua  Cao  SiYang 《Natural Hazards》2017,85(1):453-470
Natural Hazards - In this paper, we investigate the spatial and temporal distributions of rainfall in Qatar, which falls in the arid region of the middle-east. We use rainfall data from 29 rain...  相似文献   
657.
Lixin  Yi  Ke  Cheng  Xiaoying  Cao  Yueling  Sun  Xiaoqing  Cheng  Ye  He 《Natural Hazards》2017,85(2):1223-1248

Flood management consists many aspects such as hazard assessment, vulnerability assessment, exposure assessment, risk assessment, early warning system, damage assessment as well as risk mitigation planning. Conventional flood management are depending on the ground based monitoring of rainfall and river discharge. Many parts of the world are not covered by these sensor networks in one hand and these ground based systems are costly. Most of the tropical countries have high flood risk and low financial and institutional capacity to afford ground based system. While conventional flood management is time and cost intensive, spaceborne remote sensing provides timely and low-cost data in comparison to field observation, and is the obvious choice for most developing countries affected by flooding. Many aspects of flood management are being aided with the advancement of remote sensing technology. More precise and near real time flood detection, lead time in flood early warning system, accurate and advance inputs of hydrological models are now blessed by space technology. Many methods and approaches have been developed to overcome the constrains in the application of spaceborne remote sensing in flood management. Application of satellite remote sensing in flood hazard assessment is well documented, however, the application of space technology in other aspects of the flood management is also promising. Therefore, this review paper focuses on the applicability of spaceborne remote sensing and in most of the aspects in flood management.

  相似文献   
658.
The current study sought to offer guidance for developing effective web-based mapping tools for wildfire warnings by identifying (1) the important content for facilitating individuals’ decision-making, and (2) the optimal interface design for ensuring usability and ease of information access. A map-based warning tool was prototyped in the Australian context, followed by a usability and effectiveness evaluation through individual interviews and verbal protocol analysis to assess participants’ interaction with the mapping interface and information in response to the simulated warning scenario. The results demonstrated variations in participants’ approaches to wildfire warning response, revealing varied information needs. Specifically, most participants relied on their own assessment of the prospective threat, requiring specific wildfire-related information before eliciting a response. In contrast, the decision of a minority of the participants was motivated by response guidance from agencies, and accurate wildfire information was less important for their response. Imperative information for both types of residents therefore needs to be highlighted in a map-based warning tool to cater to a wide audience. Furthermore, a number of heuristics were identified for designing effective interactive functions to facilitate the control of, and access to, the various maps and textual information presented on the map-based warning interface.  相似文献   
659.
To elucidate the molecular response of shrimp hepatopancreas to white spot syndrome virus (WSSV) infection, microarray was applied to investigate the differentially expressed genes in the hepatopancreas of ‘Huanghai No. 2’ (Fenneropenaeus chinensis). A total of 59137 unigenes were designed onto a custom-made 60K Agilent chip. After infection, the gene expression profiles in the hepatopancreas of the shrimp with a lower viral load at early (48–96 h), peak (168–192 h) and late (264–288 h) infection phases were analyzed. Of 18704 differentially expressed genes, 6412 were annotated. In total, 5453 differentially expressed genes (1916 annotated) expressed at all three phases, and most of the annotated were either up- or down-regulated continuously. These genes function diversely in, for example, immune response, cytoskeletal system, signal transduction, stress resistance, protein synthesis and processing, metabolism among others. Some of the immune-related genes, including antilipopolysaccharide factor, Kazal-type proteinase inhibitor, C-type lectin and serine protease encoding genes, were up-regulated after WSSV infection. These genes have been reported to be involved in the anti-WSSV responses. The expression of genes related to the cytoskeletal system, including β-actin and myosin but without tubulin genes, were down-regulated after WSSV infection. Astakine was found for the first time in the WSSV-infected F. chinensis. To further confirm the expression of differentially expressed genes, quantitative real-time PCR was performed to test the expression of eight randomly selected genes and verified the reliability and accuracy of the microarray expression analysis. The data will provide valuable information to understanding the immune mechanism of shrimp’s response to WSSV.  相似文献   
660.
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