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111.
Bungonia Caves are the result of three distinct phases of speleogenesis. The first, Late Cretaceous phase is characterised by the development of horizontal passages close to the plateau surface. Caves developed in the lower limestone during this phase probably drained southward to risings in Becks Gully. The second, Palaeocene phase resulted in the development of dolines and large dynamic phreatic conduits. Caves extended to depths approximating the level of the Efflux and drainage from caves in the lower limestone was captured by the caves in the middle limestone, rising above the level of the Efflux. The second phase ended when the caves were filled with laminated clays, blocking underground drainage, and the surface was buried by quartz‐rich fluvial sediments prior to the Eocene. The third, and continuing phase, which began in the Late Tertiary, is characterised by the development of vadose shafts and by the removal of sediment deposited following the second phase.  相似文献   
112.
People have been exploiting the limestone massifs of the Venetian Fore-Alps since prehistory. The fluviokarstic style of the relief and the location of springs were important controls of settlement and land use. Six principal types of exploitation are recognized and overlapped in time: (1) hunting and early farming, Paleolithic to Iron Age, with the first soil erosion; (2) general deforestation for timber, charcoal, and fuel, Roman to early modern; (3) farm enclosure and improvement, with stone clearing, medieval to modern; (4) trench warfare in World War I; (5) quarrying and specialized farming (dairy, poultry, pigs) since 1950; and (6) developmnent of modern summer and winter tourist facilities. Soil erosion effects from many centuries can still be recognized, war damage remains visible and continues to pollute aquifers, and modern pressure on the karst land and water resources is often severe.  相似文献   
113.
本文在分析筠连温泉岩溶风景区旅游景观资源特点的基础上,应用类比法研究的一般原理,将其与美国阿肯色州的温泉国家公园进行了定性类比和定量对比,得出筠连温泉岩溶风景名胜区的旅游景观资源,无论在品质上和丰度上,均与美国温泉国家公园类同的明确结论。  相似文献   
114.
Thermal mineral water springs in Karlovy Vary   总被引:1,自引:0,他引:1  
In the western part of the Czech Republic about 130–180 km west of the capital of Prague, in an area of about 300 sq km, several dozen mineral springs occur from various origins, with water of different chemical characteristics, temperatures, and levels of carbonation and radioactive intensity. Mineral waters are widely utilized, in particular for spa treatment of a broad range of ailments as well as for bottling (curative and table waters), industrial uses of carbon dioxide, evaporation for the salts dissolved in them and, in regard to thermal waters, for local heating.  相似文献   
115.
中国东北地区地热资源及热结构分析   总被引:1,自引:0,他引:1  
在我国东北地区,盆地的热流高而在山区和地台区(额尔古纳和佳木斯地台)热流较低,通过对该区的研究发现,在地壳和上地幔中莫霍面埋深,高导层埋深和热流值之间存在着密切的联系,通过对该区热流数据分析我们可以得到这样的结论:该区的地壳和上地幔的热结构引起了热流分布的变化。计算结果还表明,该区地台的地幔热流,地壳中10km以下和10km以上的热流对地表热流的贡献不同。该区松辽盆地中广泛分布着传导型中低温地热资源,对松辽盆地地热资源的开发利用有着广泛的前景。最后结合已有的地质和物探资料,还给出了长白山天池火山地区长白温泉地热系统的概念性模型。  相似文献   
116.
重庆金佛山泉水地球化学特征及其空间分布意义   总被引:2,自引:1,他引:1       下载免费PDF全文
2006年7月和9月在重庆金佛山地区选取22个地下水出露的泉点.对泉水的地球化学性质进行详细调查。利用野外和实验室测量手段得到了主要阴离子和阳离子浓度与物理化学参数。分析得知:研究区泉水的水化学类型为Ca-HCO_3和Ca、Mg-HCO_3;结合地质和地貌背景把它们分为6个泉群,分别讨论各泉群的空间分布意义;估算泉水方解石(SI_C)、白云石(SI_D)和石膏(SI_G)的饱和指数,即可反映地层岩性、地形和地下水的运移时间对水质的影响,该区地下水基本上是来自大气降水的下渗.没有深部含水层的上升混合.这些泉水的地球化学特征以及它们的空间分布规律能够很好地反映区内地质状况.该研究可以为金佛山地区地下水资源的调查和环境保护提供基础数据。  相似文献   
117.
 Experimental modelling methods are used for prediction of deformation and groundwater outflows at the bottom of an open-pit mine during the excavation of brown coal. Thermal gas-bearing artesian water exerts an uplift pressure on the impervious subsoil of the coal seam and threatens the stability of the mine bottom. The breakthrough of the mine bottom would seriously affect the groundwater regime and may endanger mining activities. The mining is carried out within the protection zones of the Carlsbad spa springs. Results of model studies are used to determine protective hydrogeological and mining measures for providing the maximum protection for the open-pit mine and the spa springs. Received: 16 August 1996 · Accepted: 9 June 1997  相似文献   
118.
Artesian springs, which form carbonate mounds at the surface, occur in groups along the southwestern edge of the Great Artesian Basin (GAB), in northern South Australia. Their underground structure and relationship to faulting are not well understood. This study investigated four mound spring groups (Beresford Spring, Warburton Spring, the Bubbler Spring group, and Freeling Springs), which have different geological settings, using a range of geophysical techniques: self-potential (SP), magnetotellurics (MT) and time-domain electromagnetics (TEM). The results confirmed that despite generally similar mound morphologies at the surface, spring vents in different groups have different mechanisms for sourcing water from the GAB aquifer. SP measurements effectively showed where most of the vertical flow occurs at all groups, while MT and TEM models identified the location of faults, other geological structures and the thickness of the Bulldog Shale aquitard. Beresford and Warburton springs are similar in that the spring locations at both are directly related to points on a regional-scale fault, which appears to provide a low permeability pathway to the surface. At the Bubbler Springs group, a regionally aligned fault identified in MT data seems to be bounding an area where the aquifer is much closer to the surface (and the overlying aquitard has been thinned) where the spring abundance is highest. SP responses indicate that shallow flow paths feeding individual vents are unrelated to the fault. At Freeling Springs, the SP suggests that groundwater is flowing up within shallow aquifers, and that spring location is offset from this upward flow, instead located on range-front faults that provide the final conduit to the surface.  相似文献   
119.
Thermal groundwater is currently being exploited for district-scale heating in many locations world-wide. The chemical compositions of these thermal waters reflect the provenance and circulation patterns of the groundwater, which are controlled by recharge, rock type and geological structure. Exploring the provenance of these waters using multivariate statistical analysis (MSA) techniques increases our understanding of the hydrothermal circulation systems, and provides a reliable tool for assessing these resources.Hydrochemical data from thermal springs situated in the Carboniferous Dublin Basin in east-central Ireland were explored using MSA, including hierarchical cluster analysis (HCA) and principal component analysis (PCA), to investigate the source aquifers of the thermal groundwaters. To take into account the compositional nature of the hydrochemical data, compositional data analysis (CoDa) techniques were used to process the data prior to the MSA.The results of the MSA were examined alongside detailed time-lapse temperature measurements from several of the springs, and indicate the influence of three important hydrogeological processes on the hydrochemistry of the thermal waters: 1) salinity and increased water-rock interaction; 2) dissolution of carbonates; and 3) dissolution of sulfides, sulfates and oxides associated with mineral deposits. The use of MSA within the CoDa framework identified subtle temporal variations in the hydrochemistry of the thermal springs, which could not be identified with more traditional graphing methods, or with a standard statistical approach. The MSA was successful in distinguishing different geological settings and different annual behaviours within the group of springs. This study demonstrates the usefulness of the application of MSA within the CoDa framework in order to better understand the underlying controlling processes governing the hydrochemistry of a group of thermal springs in a low-enthalpy setting.  相似文献   
120.
Geochemical studies on cold meteoric waters, post-1980 hot spring waters, fumarole emissions from the dacite dome, and volcanic rocks at Mount St. Helens (MSH) from 1985 to 1989 show that magmatic volatiles are involved in the formation of a new hydrothermal system. Hot spring waters are enriched in 18O by as much as 2 and display enrichments in D relative to cold waters. A well-defined isotopic trend is displayed by the isotopic composition of a>400°C fumarole condensate collected from the central crater in 1980 (-33 D, +6 18O), of condensate samples collected on the dome, and of cold meteoric and hot spring waters. The trend indicates that mixing occurs between local meteoric water and magmatic water degassing from the dacite dome. Between 30 and 70% magmatic water is present in the dome fumarole discharges and 10% magnatic water has been added to the waters of the hydrothermal system. Relations between Cl, SO4 and HCO3 indicate that the hot spring waters are immature volcanic waters formed by reaction of rocks with waters generated by absorption of acidic volcanic fluids. In addition, the B/Cl ratios of the spring waters are similar to the B/Cl ratios of the fumarole condensates (0.02), values of 13C in the HCO3 of the hot springs (-9.5 to-13.5) are similar to the magmatic value at MSH (-10.5), and the 3He/4He ratio, relative to air, in a hot spring water is 5.7, suggesting a magmatic origin for this component.managed by Martin Marietta Energy Systems, Inc., under contract DE-AC05-84OR21400 with the US Department of Energy  相似文献   
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