岩溶洞穴中钟乳石类沉积物色泽变化的成因浅析   总被引：2，自引：0，他引：2  

闫志为 《中国岩溶》2004,23(2):129-132

在溶洞开发利用过程中发现,一些原为晶莹洁白的洞内钟乳石类沉积物逐渐变得色泽暗淡发红或产生其它颜色,失去了原有的亮丽色泽。笔者认为产生这种现象的主要原因是由于洞穴开放程度增高或当地气候等环境条件发生较大变化,增强了洞内空气与洞外大气的循环交替,洞内空气中氧含量增大,造成渗入洞中水氧化还原条件发生较大变化,致使铁、锰等金属化合物在钟乳石类沉积物中沉积所致。此外,泥质、有机质以及其它金属矿物等在钟乳石类沉积物表面的沉积或附着,也是促使颜色变化的另一原因。   相似文献   

Oxygen and carbon isotopic characteristics of rainwater, drip water and present speleothems in a cave in Guilin area, and their environmental meanings   总被引：16，自引：0，他引：16  

LI Bin  YUAN Daoxian  QIN Jiaming  LIN Yushi  ZHANG Meiliang 《中国科学D辑(英文版)》2000,43(3):18-285

The studies of the oxgen and carbon isotopes of the rainwater in Guilin area, the drip water and the present carbonate deposit in Panlong cave of Guilin show that: (i) as to the general characteristics of the oxygen isotopes of the rainwater within a year and between years, the δ18O values decrease with an increase of air temperature and the rainfall, and the correlation between δ18O values and the mean monthly air temperature is much better than that between δ18O values and the rainfall, and the δ18O values of the rainwater during the summer monsoon are much smaller than those during winter monsoon; (ii) δ18O values of the drip water have a quite good correlation with the δ18O values of the rainwater in the same period; (iii) when the conditions are appropriate, δ13C can be used as an environmental proxy, that is, the smaller δ13C of speleothems is, the larger the proportion of C3 plants is and the more plentiful the rainfall is. On the contrary, C4 plants may be prevailing or the environment may be a stony desert caused by climate changes or human activity.  相似文献   

中国洞穴无脊椎动物的研究概况     

李学珍  牛长缨  雷朝亮  韩道山 《中国岩溶》2007,26(3):255-261

我国喀斯特地貌发育强烈,主要分布在滇、黔、桂、湘、川、渝、鄂、浙等省区,洞穴无脊椎动物的研究也主要集中在这些省份。本文介绍了我国洞穴无脊椎动物研究的简史,列出了近20多年来我国发现的真洞穴无脊椎动物种类,并根据栖息环境的不同,将洞穴无脊椎动物划分为陆生群落和水生群落;着重介绍了蛛形纲、重足纲、昆虫纲、甲壳纲、腹足纲的研究现状。此外,对洞穴无脊椎动物的生态特征以及进化研究也进行了概述。然而,我国洞穴无脊椎动物的研究在国内重视程度不够,与国外同类研究相比还存在一定的距离。因此,深入系统地研究洞穴无脊椎动物,加大洞穴生物保护的宣传力度,防止生物多样性的流失,将是未来中国洞穴无脊椎动物研究前进的方向。   相似文献   

天然荧光物质作为岩溶地下水的示踪剂研究——以湖北清江和尚洞为例   总被引：1，自引：1，他引：0  

贾苒  胡超涌  邱海鸥  何璐瑶 《中国岩溶》2007,26(3):262-265

天然荧光物质作为岩溶地下水的示踪剂的相关报道较少。在详细研究了湖北清江和尚洞岩溶滴水中荧光物质的光谱特征及其季节变化的基础上,探讨了天然荧光物质作为岩溶示踪剂的可行性。研究结果表明,和尚洞岩溶滴水中的主要荧光物质是富里酸,其特征波长对为: 激发波长304nm,发射波长407nm。在年季旋回中,荧光强度与滴水的氧同位素组成有一致的季节变化( r = 0. 539, p >0. 99)。滴水δ18O和荧光强度峰值( 5月,初夏)出现明显滞后于补给水(冬季降水) ,两者的时间差指示了岩溶水的滞留。因此,天然荧光物质作为一种新型的地下水的示踪剂,具有灵敏、经济及环保等特点,特别适合源头未知的岩溶水示踪。   相似文献   

广丰县天桂岩石灰岩溶洞特征及旅游开发远景     

廖洪鑫 《江西地质》2000,14(2):123-126

本文在阐述天桂岩石灰岩溶洞规模,形态特征的基础上,对洞穴旅游开发远景作了初步评价,并提出开发建议,认为实行综合性的立体开发,能够提高其旅游价值。  相似文献   

浙江瑶琳洞风化碳酸钙景观复生试验   总被引：15，自引：0，他引：15  

宋林华  杨京蓉  林钧枢  王来洪  俞锦标  张汝凡  谭明 《地理研究》1999,18(2):199-206

目前,世界上80%以上的风景旅游洞穴,开放后,大量游客涌入和高能景观灯的应用,洞穴环境及能量埸和化学埸发生了巨大变化,洞穴碳酸钙景观遭受严重破坏,其景观的美学价值大大降低。文中论述了在已遭风化破坏的碳酸钙景观上滴喷高Ca⁺²碱液,吸收洞穴空气CO₂,形成CaCO₃沉积层的试验。试验结果表明,Ca⁺²碱液滴喷技术可以恢复风化碳酸钙景观的美学度,同时又降低洞穴空气中的浓度,改善洞穴环境。  相似文献   

Reconstructing fluvial incision rates based on palaeo-water tables in chalk karst networks along the Seine valley (Normandy,France)     

Carole Nehme  Andrew Farrant  Daniel Ballesteros  Dominique Todisco  Joel Rodet  Diana Sahy  J. Michael Grappone  Jean-Claude Staigre  Damase Mouralis 《地球表面变化过程与地形》2020,45(8):1860-1876

Quantifying rates of river incision and continental uplift over Quaternary timescales offer the potential for modelling landscape change due to tectonic and climatic forcing. In many areas, river terraces form datable archives that help constrain the timing and rate of valley incision. However, old river terraces, with high-level deposits, are prone to weathering and often lack datable material. Where valleys are incised through karst areas, caves and sediments can be used to reconstruct the landscape evolution because they can record the elevation of palaeo-water tables and contain preserved datable material. In Normandy (N. France), the Seine River is entrenched into an extensive karstic chalk plateau. Previous estimates of valley incision were hampered by the lack of preserved datable fluvial terraces. A stack of abandoned phreatic cave passages preserved in the sides of the Seine valley can be used to reconstruct the landscape evolution of the region. Combining geomorphological observations, palaeomagnetic and U/Th dating of speleothem and sediments in eight caves along the Lower Seine valley, we have constructed a new age model for cave development and valley incision. Six identified cave levels up to ∼100 m a.s.l. were formed during the last ~1 Ma, coeval with the incision of the Seine River. Passage morphologies indicate that the caves formed in a shallow phreatic/epiphreatic setting, modified by sediment influxes. The valley's maximum age is constrained by the occurrence of late Pliocene marine sand. Palaeomagnetic dating of cave infills indicates that the highest-level caves were being infilled prior to 1.1 Ma. The evidence from the studied caves, complemented by fluvial terrace sequences, indicates that rapid river incision occurred during marine isotope stage (MIS) 28 to 20 (0.8–1 Ma), with maximal rates of ~0.30 m ka⁻¹, dropping to ~0.08 m ka⁻¹ between MIS 20–11 (0.8–0.4 Ma) and 0.05 m ka⁻¹ from MIS 5 to the present time. © 2020 John Wiley & Sons, Ltd.  相似文献   

Kinetic processes and stable isotopes in cave dripwaters as indicators of winter severity          下载免费PDF全文

Vasile Ersek  Bogdan P. Onac  Aurel Perșoiu 《水文研究》2018,32(18):2856-2862

We examine how the stable isotope composition of meteoric water is transmitted through soil and epikarst to dripwaters in a cave in western Romania. δ²H and δ¹⁸O in precipitation at this site are influenced by temperature and moisture sources (Atlantic and Mediterranean), with lower δ¹⁸O in winter and higher in summer. The stable isotope composition of cave dripwaters mimics this seasonal pattern of low and high δ¹⁸O, but the onset and end of freezing conditions in the winter season are marked by sharp transitions in the isotopic signature of cave dripwaters of approximately 1 ‰. We interpret these shifts as the result of kinetic isotopic fractionation during the transition phase from water to ice at the onset of freezing conditions and the input of meltwater to the cave at the beginning of the spring season. This process is captured in dripwaters and therefore speleothems from Ur?ilor Cave, which grew under such dripping points, may have the potential to record past changes in the severity of winters. Similar isotopic changes in dripwaters driven by freeze–thaw processes can affect other caves in areas with winter snow cover, and cave monitoring during such changes is essential in linking the isotopic variability in dripwaters and speleothems to surface climate.  相似文献   

Late quaternary speleogenesis and landscape evolution in the northern Apennine evaporite areas          下载免费PDF全文

Andrea Columbu  Veronica Chiarini  Jo De Waele  Russell Drysdale  Jon Woodhead  John Hellstrom  Paolo Forti 《地球表面变化过程与地形》2017,42(10):1447-1459

Gypsum beds host the majority of the caves in the north‐eastern flank of the Apennines, in the Emilia Romagna region (Italy). More than six hundred of these caves have been surveyed, including the longest known epigenic gypsum cave systems in the world (Spipola‐Acquafredda, ~11 km). Although this area has been intensively studied from a geological point of view, the age of the caves has never been investigated in detail. The rapid dissolution of gypsum and uplift history of the area have led to the long‐held view that speleogenesis commenced only during the last 130 000 years. Epigenic caves only form when the surface drainage system efficiently conveys water into the underground. In the study area, this was achieved after the dismantling of most of the impervious sediments covering the gypsum and the development of protovalleys and sinkholes. The time necessary for these processes can by constrained by understanding when caves were first formed. The minimum age of karst voids can be indirectly estimated by dating the infilling sediments. U–Th dating of carbonate speleothems growing in gypsum caves has been applied to 20 samples from 14 different caves from the Spipola‐Acquafredda, Monte Tondo‐Re Tiberio, Stella‐Rio Basino, Monte Mauro, and Castelnuovo systems. The results show that: (i) caves have been forming since at least ~600 kyr ago; (ii) the peak of speleogenesis was reached during relatively cold climate stages, when rivers formed terraces at the surface and aggradation caused paragenesis in the stable cave levels; (iii) ~200 000 years were necessary for the dismantling of most of the sediments covering the karstifiable gypsum and the development of a surface mature drainage network. Besides providing a significant contribution to the understanding of evaporite karst evolution in the Apennines, this study refines our knowledge on the timescale of geomorphological processes in a region affected by rapid uplifting. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

三维激光扫描技术在溶洞探测中的应用     

刘兴权  阎曼  杨厚波 《测绘工程》2010,19(5):41-43

由于溶洞的特殊性,传统测量仪器已经不能满足当前对溶洞探测的要求。三维激光扫描技术采用非接触式高速激光测量方式,能在复杂的现场和空间对被测物体进行快速扫描测量,从而获得点云数据。文中介绍激光扫描的工作原理及三维激光扫描的工作流程,并给出采用Riegl LMS_Z420i三维激光扫描仪对吉首至茶洞高速公路吉首岸索塔基坑下的溶洞进行探测的实例。  相似文献