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81.
Karst groundwater protection in the Kupa River catchment area and sustainable development 总被引:1,自引:0,他引:1
One of the most significant water resources in the Republic of Croatia is the catchment area of the Kupa River, located in
the region bordering the Republic of Slovenia. About 88% of the total amount of water in this catchment originates in Croatia
and just 12% from Slovenia; therefore, the largest part of the catchment area (about 1000 km2) is on the Croatian side of the border. It is a typical karst area of the Dinarides with aquifers characterized by a relatively
rapid water exchange, high groundwater flow velocities and aquifers open to human impact from the surface. Consequently, the
aquifers are highly vulnerable and at risk. Due to the availability of large quantities of high-quality spring water (about
6 m3/s), the entire area has a strategic importance within the context of any future development strategy pertaining to the western
part of Croatia. The catchment area on the Croatian side was investigated using a wide range of research methods that included
a classical hydrogeological approach, the detailed hydrologic calculation of water balance to the hydrogeochemical analyses
and modelling. The objective was to determine protection zones and protection measures for the whole area. The difficulties
are increased due to the fact that the karst catchment area is crossed by major traffic corridors, oil pipelines and a railway
and that many settlements and a highly developed wood industry are present. The combination of protecting water resources
with adequate prevention measures and necessary remedial activities that should satisfy the very strict requirements necessary
for the protection of the karst aquifers while still allowing for present and future human activities is difficult – but not
impossible – to achieve. One good example is the present highway with a closed dewatering system and waste water treatment
before the water passes into the karst underground system. 相似文献
82.
黄腊石滑坡是发育在三叠系中统巴东组砂泥岩夹灰岩构成的逆倾坡上的滑坡群,总方量约1 800×104 m3.滑坡滑带下面存在着大致连续分布的基岩弯曲松弛带.对于该松弛带工程地质特性的认识,将影响防治工程方案的设计及实施.本文通过野外工作、以往工作资料和研究成果的收集整理及再认识,对该滑坡下伏松弛带工程地质特性、形成机制及失稳预测作了一定深度的探讨,认为基岩弯曲松弛带是发生在特定的岩层中,由构造、重力、侵蚀、岩溶、风化、降雨及上部滑坡等因素共同作用的产物,工程地质环境质量较差,受重力及其上滑体滑动等因素影响,后期改造明显.在斜坡长期受重力累积变形、三峡水库运行期江水位变化及库岸再造作用下,将形成牵引式滑动.防治工程应在削方、排水等基础上,重点考虑防止库岸再造和斜坡坡脚部位变形. 相似文献
83.
黔东地区变质核杂岩构造及其控矿作用 总被引:1,自引:0,他引:1
黔东地区的变质核杂岩构造其变质核杂岩为中元古界四堡群、梵净山群变质基底,其主滑脱面发育于新元古界底部的甲路组,同时在下江群、板溪群中出现一系列次级滑脱面,在其上的早古生代地层中则发育伸展剥离正断层系统。该类型构造形成于加里东期末,是该区加里东造山期后隆升背景的产物。变质核杂岩构造与该地区的金、铜、铅、锌、锑及汞等矿产关系十分密切,它们分别受控于主滑脱带、次级滑脱带及伸展剥离正断层系统,且在剖面上矿物组合、成矿温度出现有规律变化,反映出该地区金及多金属矿产是受控于变质核杂岩构造的一个完整的、相互有机联系的成矿系统。 相似文献
84.
夏季季风转换期间南沙群岛海域的温盐分布特征 总被引:2,自引:0,他引:2
应用2002年5月9-22日南沙群岛海域的水文观测资料,分析了季风转换期间南沙群岛海域的水文状况,并对比了调查海域不同区域的温盐分布特征。结果表明,夏季风转换期间海洋表层温度较高,基本在30℃以上,垂直结构上温度层结比较稳定。东北一西南走向界线两侧海域的温盐状况有明显的差异:西北部海域温度较高,垂向上有逆盐层现象;东南部海域温度相对较低,盐度的垂向结构上显示有双跃层现象,两海区水文特征的差异与季风结构和局地环流有密切的关系。从连续站温盐的时空剖面图可以看到,跃层以下,不规则的半日周期内潮对温盐分布有显著的影响。 相似文献
85.
Wei ZHANG Chuanchuan LI Zhijiu CUI Jinliang FENG . College of Urban Environmental Sciences Liaoning Normal University Dalian Liaoning China. College of Environmental Sciences Peking University Beijing China 《东北亚地学研究》2008,11(3):156-167
This paper presents the study on two continuous glacio-lacustrine sedimentary deposits, Laotanfang (3 597 m) and Shibantang (3 689 m) located on the southern and northern sides of Hulifang peak in Yunan, China. Environmental change indexes are constructed for each deposit, based on grain size, geochemical and pollen analysis, environmental magnetic susceptibility, and 14C dating. The study of climatic environmental change since the Holocene epoch in this region shows that the climate fluctuated at different stages during the early Holocene, that is, the climate was cool and wet during 8.4-7. 7r ka, cold and wet during 7.7-6. 5 ka, cold and dry during 6. 5-4.7 ka, cool and wet during 4.7-2. 1 ka, warm and wet during 2. 1-1.0 ka, and warmer and wet since 1 ka. These findings reflect the overlapping influences of the southwest and southeast monsoons in different times during the Holocene in the north part of southwestern China are in accord with other Holocene climate change models in this part of China. 相似文献
86.
与豫西小秦岭和熊耳山地区相类似,崤山北部也出露一系列中酸性小岩体,但与之相关的成矿作用明显较弱,因此长期未获得应有的关注。崤山北部小岩体的形成时代与区域成岩成矿时代之间的匹配关系对其深部构造演化研究及成矿潜力评价具有重要意义,鉴于此,作者对后河岩体进行了LA-ICP-MS锆石U-Pb定年。后河岩体定年样品HH01的岩性为中-细粒黑云母二长花岗岩,30个锆石测点中有27个测点的测定值位于207Pb/235U-206Pb/238U一致线上,相应的206Pb/238U年龄介于124~134 Ma之间,加权平均年龄为128±1Ma(MSWD=1.02),属早白垩世。后河岩体是岩石圈拆沉作用的产物,其形成时代处在东秦岭地区广泛而强烈的成岩成矿作用时限内,且显示了Au、Ag、Cu、Mo、W等元素的异常富集,具有较大的内生金属成矿潜力。 相似文献
87.
88.
A. Geddes D.A. Elston M.E.A. Hodgson R. V. Birnie 《International journal of geographical information science》2013,27(4):785-803
Handling of uncertainty in the estimation of values from source areas to target areas poses a challenge in areal interpolation research. Stochastic model-based methods offer a basis for incorporating such uncertainty, but to date they have not been widely adopted by the GIS community. In this article, we propose one use of such methods based in the problem of interpolating count data from a source set of zones (parishes) to a more widely used target zone geography (postcode sectors). The model developed also uses ancillary statistical count data for a third set of areas nested within both source and target zones. The interpolation procedure was implemented within a Bayesian statistical framework using Markov chain Monte Carlo methods, enabling us to take account of all sources of uncertainty included in the model. Distributions of estimated values at the target zone level are presented using both summary statistics and as individual realisations selected to illustrate the degree of uncertainty in the interpolation results. We aim to describe the use of such stochastic approaches in an accessible way and to highlight the need for quantifying estimation uncertainty arising in areal interpolation, especially given the implications arising when interpolated values are used in subsequent analyses of relationships. 相似文献
89.
右江盆地沉积连续的泥盆纪—石炭纪岩石地层,是中国泥盆纪与石炭纪之交Hangenberg生物大灭绝事件的重点研究区域。选取右江盆地西缘云南富宁地区晚泥盆世—早石炭世地层,在岩石地层学研究的基础上对碳酸盐岩进行系统的碳、氧同位素组成研究。富宁地区晚泥盆世—早石炭世地层存在不同幅度的δ13C、δ18O负向偏移,尤其在泥盆系—石炭系界线附近负偏移明显,δ13C、δ18O值偏移层位与层序地层学转换及古生物灭绝事件发生层位一致,反映了晚泥盆世法门期海平面下降和早石炭世的海侵事件。研究区泥盆系—石炭系界线附近δ13C值负偏趋势与右江盆地内δ13C值演化偏移相似,华南其他典型剖面δ13C值亦呈现不同幅度的负向偏移,泥盆纪与石炭纪之交的碳同位素演化序列与欧洲、北美地区δ13C值负向偏移反映的海平面下降事件一致,具全球性对比意义。 相似文献
90.
根据1∶5万仲巴地区区域地质调查,对雅鲁藏布江缝合带西段夹持于2套混杂岩之间的仲巴微地体原二叠系曲嘎组进行了拆解。研究认为:①原曲嘎组可以解体为3套地层,分别是下古生界的奥陶系—志留系紫曲浦群、上古生界泥盆系纳登尔组和石炭系—二叠系曲嘎群,新建曲嘎群与原曲嘎组没有直接对应或者级别关系;②紫曲浦群以变质碳酸盐岩为主,下部紫曲电站组为紫红色、灰色大理岩与结晶灰岩组合,属中—晚奥陶世,上部紫曲石组以紫红色大理岩为特征,暂归志留纪;③纳登尔组由一套灰色千枚状板岩和钙质片岩组成,上部结晶灰岩增多,时代为泥盆纪,可归属马攸木群;④曲嘎群可划分为3个组:岗珠淌组,以灰色、灰绿色板岩、粉砂岩为主,向上砂岩和灰岩增多,属于石炭纪—早二叠世(乌拉尔世)早期;仲巴组,以肉红色灰质晶粒白云岩及杂色生物屑云质灰岩为特点,分为2个岩性段,属于早—中二叠世(乌拉尔世—瓜德鲁普世早中期);卡扎勒组以深灰色钙质板岩为主或夹结晶灰岩和砂岩或互层,属于中—晚二叠世(瓜德鲁普世—乐平世);⑤仲巴地区曲嘎组的拆解在仲巴微地体西部和老仲巴以东的应用有待证实,其在岩性上与相邻地体同期地层有较大差别,但在生物群组成方面具有相似性。 相似文献