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131.
湖泊湿地生态地球化学评价的研究重点为湖泊湿地生态系统中的重金属、植物营养元素及一些有机污染物,评价标准体系相应地包括水质基准、营养物基准、水体沉积物质量基准、饮用水卫生标准、土壤环境质量标准、食品卫生标准、湖泊水库富营养化标准等。  相似文献   
132.
金龙山——丘岭金矿区含金矿源为层上泥盆统南羊山组和下石炭统袁家沟组。组成含金矿源层岩石为高频互层的细碎屑岩-碳酸盐岩,其中细砂岩、粉砂岩、碳酸盐岩含成矿流体物性较好.页岩、板岩含成矿流体物性较差,构成屏蔽层。金鸡岭Ⅰ级复式向斜控制着金、砷、锑等异常范围;松枣Ⅱ级复式背斜控制着金的矿化带;金龙山-丘岭金矿Ⅲ级背斜控制着金的矿(化)体;镇安——板岩镇断裂的次级断裂是金矿化体的容矿有利位置。在成矿过程中,构造变形与成矿流体的形成、运移及储集密切相关。其规律是:①原生构造导致成矿流体的初次聚集。②第一期构造变形导致成矿流体的聚集。③第二期构造变形导致成矿流体运移及金矿床形成。此期变形是金的主要成矿期。④第三期构造变形使成矿流体进一步聚集和金矿体的富集。⑤第四期构造变形是石英方解石脉的形成时期。总结出矿床形成模式。据此提出了在4种不同的构造部位找金的方向。  相似文献   
133.
为求出嵌岩桩嵌岩段侧摩阻力的表达式,假定嵌岩桩桩侧破坏由桩岩接触面上的滑动引起,桩岩接触面的压力由加载前岩土层自重产生的侧压力和由剪切膨胀产生的应力增量组成。用弹性力学的方法求解出桩侧正应力,引入了岩石破坏的Hoek-Brown强度准则,由此求出了嵌岩段桩侧阻力的表达式,并指出了此公式的适用范围。最后结合工程实际进行了对比分析,表明本文方法具有一定的实用性。  相似文献   
134.
The present work proposes an approach to adapt existing isotropic models to transversely isotropic materials. The main idea is to introduce equivalence relations between the real material and a fictitious isotropic one on which one can take all the advantages of the well‐established isotropic theory. Two applications of this approach are presented here: a failure criterion and a damage model that takes into account the load‐induced anisotropy. In both cases, theoretical predictions are in agreement with the experimental data. In the present paper, the developed approach is applied to sedimentary rock materials; nevertheless, it can be generalized to any material that exhibits transverse isotropy. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
135.
西宝山耐火黏土矿为沉积型矿床,目前揭露1个耐火黏土矿矿层,赋存于石盒子群万山组底部“B”层黏土岩的下部,厚度较稳定,勘查开发潜力较大。通过对其地质特征、矿层特征、矿石结构构造及矿床成因分析,提出了找矿方向。认为该耐火黏土矿受沉积地层控制,呈层状分布,分布较稳定。依据该区地层产出情况,在青龙山断裂与禹王山断裂之间及两侧均具有良好的找矿前景,这为下一步找矿工作奠定了基础。  相似文献   
136.
正20142366Bi Yuanqing(Institute of Geophysical and Geochemical Survey Technology of Anhui Province,Hefei 230022,China);Fang Junhua Analysis of Ore-Prospecting Potential in the Taojiaxiang Mining Site,Zongyang County(Geology of Anhui,ISSN1005-6157,CN34-1111/P,23(4),2013,p.256-260,5illus.,10refs.)  相似文献   
137.
One of the key concerns in estuarine and coastal environments is eutrophication, which is known to be closely connected to nutrient enrichment. To control and improve surface water quality, nutrient criteria are recommended in order to provide reference conditions for the environment. However, the current datasets of nutrient criteria in China are either designed for surface water or sea water, and as such these are not suitable for assessing estuarine water quality, especially given the unique ecosystem and dynamic properties of estuaries. To address this issue in current estuarine water management, nutrient criteria have been developed for a local estuary in the southeast of China. Segmentation of the Jiulong River Estuary, China was firstly analysed through field investigations carried out during 2013–2014, which resulted in the delineation of three segments characterized by their distinct properties in relation to salinity, hydrology, ecosystems, etc. Historical records from 1997 to 2014 were then analysed using statistical modelling to develop candidate nutrient criteria for the estuary.This stage of the analysis was undertaken in combination with the study of nutrient status records from the 1980s,which were used to establish a baseline reference condition. The recommended criteria values of dissolved inorganic nitrogen(DIN) in Segments Ⅰ, Ⅱ and Ⅲ of the Jiulong River Estuary are 64, 21 and 14 μmol/L,respectively, and the corresponding values for soluble reactive phosphorus(SRP) are 0.89, 0.76 and 0.89 μmol/L,respectively. It should be emphasised that these values are site-dependent, and that different results may be achieved at other locations depending on the physical and biogeochemical characteristics of an estuary, or even a single site within a catchment. It is hoped that by demonstrating a possible methodological approach and methods of nutrient criteria derivation in the Jiulong River Estuary, the current study will offer researchers some fundamental basis from which to begin to develop more complete nutrient criteria indices for the study of nutrient conditions in other estuaries throughout China.  相似文献   
138.
Cultural tourism routes can reveal and protect cultural tourism heritage by means of cultural tourism in the “time category” and the “space category”. The construction of an evaluation system for cultural tourism routes and the evaluation, scoring and grading of existing and potential cultural tourism routes are the key to the protection of heritage, history and culture along these routes, and the key to encouraging the standardization, branding and sustainable development of various formats on the routes. Yunnan cultural tourism routes are diverse and rich in resources, and their developmental foundation is good. However, the tourism development and cultural development activities occur along separate lines and there is a lack of unified management. Therefore, it is necessary to conduct research on information collection, information analysis, problem diagnosis and improvement of status in the local practices of Yunnan cultural tourism routes, and to guide the sustainable development of Yunnan cultural tourism routes. Based on the advanced experience of COE (Council of Europe), UNESCO WHC (United Nations Educational, Scientific and Cultural Organization, World Heritage Committee) and ICOMOS(International Council on Monuments and Sites), this paper comprehensively analyzes the decisive criteria for line evaluation by interpreting and summarizing the connotations of cultural tourism routes, and determines that the evaluation of cultural tourism routes should include lines. Five aspects―the theme, the participating subject, the object itself, related activities and multi-party value―are used to construct a five-component model. At the same time, based on the consumer utility function, a complete route evaluation and hierarchical system is constructed. Then, taking the Ancient Tea-horse Road cultural tourism route as an example and using the expert scoring method and the analytic hierarchy process, the actual scores and grades of the Ancient Tea-horse Road cultural tourism route are determined, and countermeasures and suggestions for its sustainable development are proposed. The paper also verifies the applicability and practicability of the evaluation system, and promotes and improves the feedback evaluation system. The aim is to at promote and widely apply the evaluation system of cultural tourism routes, realizing the transformation from individual cases to joint cases, and promoting the standardization and sustainable development of cultural tourism routes.  相似文献   
139.
正20142093Chen Daohua(Guangzhou Marine Geological Survey,Guangzhou 510075,China);Diao Shaobo The Latest Progress of Geological Marine Testing Technology in China(Rock and Mineral Analysis,ISSN0254-5357,CN11-2131/TD,32(6),2013,p.850-859,105refs.)Key words:chemical analysis,China  相似文献   
140.
梁涛 《地质与勘探》2016,52(2):239-245
为获得新的深部找矿靶区,在铁炉坪Ag多金属矿床实施了CSAMT法测深。CSAMT剖面中,高、中、低电阻率异常体边界清晰、形态各异,高阻异常体具有上、下双层结构,低阻异常体出露较小,多呈孤立形态产出,主要有400m低阻异常体和1400m低阻异常体。高阻异常体被解释为浅部和深部两层岩浆和深部流体活动的产物,推测深部高阻异常体以岩浆体系为主,浅部高阻异常体应是岩浆体系、深部流体体系及围岩硅化蚀变等的综合反映。400m低阻异常体对应于于地表剖面线400m~600m之间的主矿脉,表明它是深部成矿流体的显示,提出1400m低阻异常体为新的深部找矿靶区。  相似文献   
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