International Journal of Speleology最新文献

{"title":"Sub-recent microfauna within allogenic sediments at the bottom of a deep cave, Njemica (Biokovo Mt., Croatia)","authors":"Tomislav Kurečić, Valentina Hajek Tadesse, L. Wacha, M. Horvat, Nina Trinajstić, Ivan Mišur","doi":"10.5038/1827-806x.51.3.2428","DOIUrl":"https://doi.org/10.5038/1827-806x.51.3.2428","url":null,"abstract":"Clastic sediments deposited at the bottom of the vertical, nearly 1000 m deep Njemica Cave (Biokovo Mountain, Croatia) were analysed. Owing to the vertical morphology of the cave, the occurrences of clastic sediments are sparse. Small, up to decimetre-thick, undisturbed sediment accumulations situated near the siphon lake revealed interesting palaeontological and mineralogical data. These data are used as a useful proxy for discussing depositional processes, the provenance of the sediments and paleo-habitats of the subterranean fauna.\u0000 The sub-recent assemblages of ostracods were discovered within the sediment, and they were shown to be correlative to the known endemic species in the wider Dinaric Karst area (Pseudocypridopsis sywulai and Phreatocandona cf. motasi). The well-preserved sediment archive indicates the allogenic origin of the sediment and defines it as an allochthonous infiltrate of the Quaternary. The detritus originates from Pleistocene–Holocene deposits in the surrounding area, whose composition was influenced by volcanic activity in the wide Adriatic region. Sedimentation occurred in a calm aquatic environment by settling from suspension. Therefore the sediments are defined as slackwater deposits.","PeriodicalId":56286,"journal":{"name":"International Journal of Speleology","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42984081","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The nitrogen dynamics of Deer Cave, Sarawak, and the role of bat caves as biogeochemical sinks in Tropical Moist Forests","authors":"J. Lundberg, D. McFarlane, Guy Van Rentergem","doi":"10.5038/1827-806x.51.3.2438","DOIUrl":"https://doi.org/10.5038/1827-806x.51.3.2438","url":null,"abstract":"A better understanding of the role of bat caves as nitrogen sinks in tropical moist forest ecosystems can be expected to shed light on regional and spatial variability in nutrient recycling studies. We measured the nitrogen flux (in air and water) associated with a very large Chaerephon plicata bat colony in Deer Cave, Borneo, in the process generating a new, quantitative, estimate of the total bat population (774,828 ±48,320), and the first detailed modelling of an ammonia plume in a cave. Long-term storage of N does not occur in this wet cave. Our final budget numbers indicate that, of the daily input of N (i.e., ecologically-useful fixed-N in guano) to this cave, ammonia production is minor (and most of it is exported in water rather than air). The conclusion is that the export budget is dominated (perhaps as large as 94.4%) by microbial denitrification of fixed-N to diatomic N exported in air. Deer Cave thus acts as a nitrogen sink, potentially removing up to 39% of the ecologically-useful fixed-N from the total forest nitrogen budget over an area of hundreds of square kilometers.","PeriodicalId":56286,"journal":{"name":"International Journal of Speleology","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46334802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Airflow dynamics in Wind Cave and Jewel Cave: How do barometric caves breathe?","authors":"Annika Gomell, A. Pflitsch","doi":"10.5038/1827-806x.51.3.2437","DOIUrl":"https://doi.org/10.5038/1827-806x.51.3.2437","url":null,"abstract":"Recent research on air pressure propagation through barometric caves has revealed various speleoclimatological processes, which cause a more complex relationship between surface air pressure changes and resulting pressure gradients between cave and surface air than previously assumed. So far, however, studies on barometric cave airflow have only been based on surface air pressure measurements. Thus, this study investigates and compares airflow at the openings of Wind Cave and Jewel Cave – two major barometric cave systems in South Dakota, USA – as a response to surface air pressure changes and air pressure gradients. Based on high-resolution long-term air pressure measurements from the surfaces and several locations inside the caves, as well as ultra-sonic airflow measurements at the openings, the analysis proves that for both caves, cave airflow velocity can be predicted more accurately by air pressure gradients than by previous surface air pressure changes. An inter-cave comparison also reveals substantial differences in cave airflow dynamics between Wind Cave and Jewel Cave, with the relevant period of surface air pressure variations for cave airflow velocity and the cave reaction times being significantly longer at Jewel Cave compared to Wind Cave. Therefore, the findings of this study demonstrate the effects of cave morphology on airflow and significantly contribute to a better understanding of the speleoclimatological mechanisms and dynamics of compensating airflow at the openings of barometric caves.","PeriodicalId":56286,"journal":{"name":"International Journal of Speleology","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43942632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Flow regime evolution of a major cave system in the Eastern Alps (Hirlatzhöhle, Dachstein)","authors":"Lukas Plan, Gottfried Buchegger, E. Kaminsky, G. Koltai, Tanguy Racine, J. Szczygieł","doi":"10.5038/1827-806x.51.3.2433","DOIUrl":"https://doi.org/10.5038/1827-806x.51.3.2433","url":null,"abstract":"The 116 km-long and 1560 m-deep Hirlatzhöhle is one of the major cave systems in the Northern Calcareous Alps (NCA; Austria). It is located in the NW part of the Dachstein, an extensive karst massif encompassing 576 km² with its highest point at 2995 m a.s.l. In contrast to most other caves in the NCA, Hirlatzhöhle comprises old (epi)phreatic passages located up to 1 km above the base level as well as two modern major drainage systems. The aim of this study is to define the palaeo- and the active flow conditions in combination with speleogenesis, and the age of the cave levels of Hirlatzhöhle. We use morphological as well as sedimentological studies and correlations with other caves. Another difference from cave systems in the NCA is that the majority of passages in Hirlatzhöhle are not developed within the so-called Giant Cave Level between 1200 and 1800 m a.s.l., but deeper between 800 and 1300 m. Most parts of Hirlatzhöhle developed under epiphreatic conditions as indicated by rills and condensation corrosion cupolas, which is the case for much other cave systems in the NCA. In contrast, paragenetic features like canyons and ceiling channels are relatively rare as are insoluble sediments. Elongated scallops indicate that flow velocities were high and abrasive sediments were abundant. Opposite to the nearby Dachstein-Mammuthöhle and other caves east of it that show a west-directed palaeo-flow, scallops in Hirlatzhöhle indicate a NE-directed palaeo-flow and an autogenic recharge. Modern drainage is autogenic and N- to NE-directed as well. Even though burial age dating did not give reasonable results for Hirlatzhöhle yet, the correlation with other adjacent caves suggests a Late Pliocene to Early Pleistocene age of the main palaeo-phreatic level. This is supported by an infinite U-Th age (>0.6 Ma) of a flowstone.","PeriodicalId":56286,"journal":{"name":"International Journal of Speleology","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43781634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Speleothems in sandstone crevice and boulder caves of the Elbe River Canyon, Czech Republic","authors":"J. Adamovič, Jaroslav Kukla, M. Filippi, R. Skála, N. Mészárosová","doi":"10.5038/1827-806x.51.2.2427","DOIUrl":"https://doi.org/10.5038/1827-806x.51.2.2427","url":null,"abstract":"A variety of speleothems are present in crevice and boulder caves developed in Cretaceous sandstones of the Elbe River Canyon in northern Czech Republic. A set of complementary instrumental mineralogical methods was applied to characterize the speleothems and cave dripwaters, including X-ray powder diffraction, scanning electron microscopy and microanalysis, Raman spectroscopy and optical emission spectrometry. Four morphological types were distinguished and characterized in terms of their mineral and chemical composition: 1, rusty brown mud-dominated coatings with micro-gours, composed of a mixture of clay minerals; 2, white “chalky” coatings (moonmilk) composed of calcite with minor gypsum; 3, cauliflower-shaped coralloids composed of calcite and silica in a layered structure, with gypsum layers in apical parts; 4, knob coralloids, dark gray-brown with smooth surfaces and distinctly layered structures, composed of silica (quartz, opal-A) and Si–Al phases (kaolinite) and including phosphate-rich laminae (sasaite, vashegyite, taranakite). Only modest microbial mediation of silica precipitation was observed in cauliflower-shaped coralloids while no clear signs are present in knob coralloids despite organic enrichment in the topmost layer. White “chalky” coatings and cauliflower-shaped coralloids precipitated from weakly acidic Ca-, Mg- and sulphate-rich deeper sandstone percolates. These forms are probably still active, much like the micro-gours, produced by particulate clay deposition. Formation of knob coralloids combined clay deposition and the dominant silica precipitation from pore waters similar to the present shallow acidic percolates under changing climatic conditions, probably in the Pleistocene. It was favored by specific rock lithology (quartzose sandstone with kaolinite admixture), which explains the scarcity of similar forms in sandstone caves. Concentration of knob coralloids along protruding vertical edges and the presence of wind-guided forms suggests that silica precipitation was driven by evaporation under a constant air flow.","PeriodicalId":56286,"journal":{"name":"International Journal of Speleology","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48958102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Absence of visitors during lockdown reveals natural variation in carbon dioxide level in the Glowworm Cave, Waitomo, New Zealand","authors":"D. Merritt, C. Hendy, Shannon Corkill","doi":"10.5038/1827-806x.51.2.2435","DOIUrl":"https://doi.org/10.5038/1827-806x.51.2.2435","url":null,"abstract":"Waitomo Glowworm Cave is a highly visited cave where the highlight is viewing the bioluminescence display of a large colony of glowworms. Anthropogenic carbon dioxide build-up in the cave is prevented by management of chimney-effect ventilation aided by a network of microclimate sensors. A cave door prevents ventilationunder drying conditions and promotes it when necessary to clear CO2 and when inflowing air has high relative humidity. A COVID-19-related nationwide “lockdown” in New Zealand from March 2020 resulted in neither staff nor visitors being present in the cave for 60 days, and provided an opportunity to assess the natural microclimate of the cave, especially the natural variation in partial pressure of carbon dioxide (pCO2). In addition, comparison to the previous year showed that the presence of people in the cave increased the cave temperatures but the effect was short-lived due to cave ventilation. During the period of lockdown, the daily increase of carbon dioxide partial pressure (pCO2) due to visitors was absent. When the cave door remained sealed, pCO2 varied and tended to lie at levels above that of the external atmosphere (410 ppm). Notably, rain events raised pCO2 by up to 200 ppm (v/v), which appeared to be sourced from both stream water and drip water. These natural CO2 sources rarely reached the levels associated with cave visitation. The results support current management practices that use door control to enhance cave ventilation when people are in the cave or when natural conditions (high stream levels and high drip-water levels) promote CO2 outgassing into the cave. Suppressing ventilation outside of those times reduces the risk of introducing dry air that could desiccate the glowworms.","PeriodicalId":56286,"journal":{"name":"International Journal of Speleology","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46854700","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Empirical roughness coefficients for moderate floods in an open conduit cave: Fullers stream canyon, Culverson Creek Cave System, West Virginia","authors":"Lydia T. Albright, Gregory S. Springer","doi":"10.5038/1827-806x.51.2.2436","DOIUrl":"https://doi.org/10.5038/1827-806x.51.2.2436","url":null,"abstract":"Open conduit modeling of cave stream floods can yield useful information about water velocities and shear stresses, which can in turn be used to estimate sediment transport capabilities. All such calculations require roughness coefficients for estimating energy losses and a priori knowledge of either discharge or flow depths to set model boundary conditions. However, the difficulties associated with observing in-cave floods generally preclude measuring discharge; roughness coefficients must be assumed based on channel properties. To overcome these challenges, we monitored stream flow depths in Fullers Cave, Greenbrier County, West Virginia using pressure transducers, and simultaneously measured stage and discharge in a karst window immediately upstream of the cave. Five pressure transducers were deployed opportunistically along a 93-meter-long reach in a 10+ meter high canyon averaging 1.5 to 3 meters wide. Stage-discharge relationships were determined for the karst window using an electromagnetic flow meter for floods with peak discharges of 1.66 m3 s-1 or less. The collected data was used to obtain the empirical Manning’s n roughness values, head losses, and energy gradients. Calculated floodwater velocities are comparable to values obtained from scallops on passage walls. Major energy losses were observed where breakdown partially occludes the passage. At peak flow, Manning n values average 0.053 for reaches typified as cobble-floored canyons, but n was 0.069 in the breakdown reach. Roughness values declined exponentially with increasing discharge, but friction slopes calculated using head losses show more complex relationships with discharge. Notably, n values back calculated using bed gradients differ from those calculated using measured head losses by as little as 12%, so the use of bed gradients in roughness estimations will generally yield reasonable approximations of flow conditions. Fullers Cave experiences significantly larger open conduit floods than we observed, so additional work is needed to estimate roughness coefficients for higher discharges. Our empirical roughness coefficients can be applied to similar cave passages in other caves and contexts, including modeling slot canyon-like channels, and our methods demonstrate a technique for measuring hard to obtain data. The addition of data for open conduit conduits significantly expands the range of environments that can be modeled using empirical data beyond pipe-full caves. Applications include studying flooding, sediment transport, and bedrock erosion process. All of these topics will be addressed in Fullers in the future.","PeriodicalId":56286,"journal":{"name":"International Journal of Speleology","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42473742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recreational caving impacts of visitors in a high-altitude cave in Bolivian Andes: main effects on microhabitat structure and faunal distribution","authors":"Lais Furtado Oliveira, R. Ferreira, J. Fernández, M. Souza Silva","doi":"10.5038/1827-806x.51.2.2418","DOIUrl":"https://doi.org/10.5038/1827-806x.51.2.2418","url":null,"abstract":"The cave’s physical environment can be affected by tourism activities but only a few studies evaluated how recreational use may affect the cave fauna, mainly in caves with a low number of visitors per year. To test the hypothesis that recreational use led to changes in habitat structure and invertebrate diversity, distinct scales along a cave were analyzed. Distinct areas with and without human visitation were analyzed and transects (10 x 3 m) and quadrats (1 x 1 m) were used to access the invertebrate communities and environmental traits. Thirty-two invertebrate species were recorded, among which six are troglobitic. The similarity of non- troglobitic species differed between the visited and non-visited areas. Substrate composition inside transects differed between the two areas and the differences were higher in the percentage of matrix rock and fine sediments. The distance from the entrance influenced the similarity of non-troglobitic species while troglobitic fauna responded to the proportion of sandy sediment. Inside quadrats, both matrix rock and fine sediments influenced the similarity of non-troglobitic species. Similarity of non-troglobitic species in the visited area was explained by the proportion of matrix rock in transects and quadrats. The proportion of cobbles influenced the similarity of non-troglobitic species in quadrats in the non-visited area. The non-troglobitic species richness inside quadrants was positively related to the amount of guano, wood, fine sediment, boulders, cobbles, matrix rock, sand sediment, and plant debris. Differentiation in habitat structure and faunal composition between the two areas seems to be an effect of distance from the entrance and spatial heterogeneity, but not recreational activities.","PeriodicalId":56286,"journal":{"name":"International Journal of Speleology","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45841890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sulfuric acid speleogenesis and surface landform evolution along the Vienna Basin Transfer Fault: Plavecký Karst, Slovakia","authors":"P. Bella, H. Hercman, Šimon Kdýr, P. Mikysek, P. Pruner, Juraj Littva, J. Minár, Michał Gradziński, Wojciech Wróblewski, Marek Velšmid, P. Bosák","doi":"10.5038/1827-806x.51.2.2420","DOIUrl":"https://doi.org/10.5038/1827-806x.51.2.2420","url":null,"abstract":"Hypogene caves in the Plavecký hradný vrch Hill (Western Slovakia, Central Europe) were formed by waters ascending along faults in fractured Triassic carbonates related to the horst-graben structure at the contact of the Malé Karpaty Mountains and the NE part of the Vienna Basin. The Plavecká jaskyňa and Pec caves mostly contain horizontal passages and chambers with flat corrosion bedrock floors, fissure discharge feeders, wall water-table notches, replacement pockets, as well as a few other speleogens associated with sulfuric acid speleogenesis. The low-temperature sulfuric acid development phases of the Plavecká Jaskyňa are also indicated by the presence of sulfate minerals (i.e., gypsum and jarosite).Subaerial calcite popcorn rims were precipitated from water condensation at the edges of feeding fissures that were still active as thermal vents when the water table dropped. Hydrogen sulfide involved in the sulfuric acid speleogenesis was likely derived from anhydrites and/or hydrocarbon reservoirs with sulfate-saline connate waters in the fill of the adjacent Vienna Basin. It ascended to the surface along deep-rooted sub-vertical fault zones at the contact of the Vienna Basin with neighboring mountains. Three cave levels at 295 to 283 m asl in the Pec Cave, and five levels at 225 to 214 m asl in the Plavecká jaskyňa corresponded to phases of stable local erosional base levels in the bordering part of the Vienna Basin, most likely during periods of strongly decelerated and/or interrupted subsidence. Cave levels separated by vertical differences of only a few meters may also be related to the Pleistocene climatic cycles. The subhorizontal parts of the Pec Cave are probably of late Early Pleistocene age (˃0.99–1.07 Ma?). The two highest levels of the Plavecká jaskyňa developed during the early Middle Pleistocene (˃600 ka). Fine-grained sediments in the passage at 225 m asl with normal magnetic polarity contain jarosite. The middle level of the Plavecká jaskyňa at 220 m asl was formed in the mid-Middle Pleistocene, while the lower and lowermost levels formed in the late Middle Pleistocene (˃270 ka). The water table in the lowermost cave level probably dropped after the tectonic reactivation of the Podmalokarpatská zníženina Depression just in the front of a marginal horst structure of the Malé Karpaty Mountains.","PeriodicalId":56286,"journal":{"name":"International Journal of Speleology","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43707473","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydrodynamic model for independent cold and thermo-mineral twin springs in a stratified continental karst aquifer, Camou, Arbailles Massif, Pyrénées, France","authors":"P. Audra, Jean-Yves Bigot, D. Laurent, Nathalie Vanara, Didier Cailhol, Gérard Cazenave","doi":"10.5038/1827-806x.51.2.2413","DOIUrl":"https://doi.org/10.5038/1827-806x.51.2.2413","url":null,"abstract":"The Camou springs (Arbailles Massif, French Western Pyrenees) display an unusual close association of a typically cold karstic spring that drains the Urgonian western limb of the Arbailles, and a thermo-mineral spring (33.5°C; salinity 17.7 g/L). The latter gains its mineralization at the contact of Triassic evaporites mainly through a deep loop in the Apanicé syncline. The fast upflow of this deep water occurs at the cross of large active lines (the North-Pyrenean thrust located at depth, and the Saison transverse fault). Cave diving in the nearby Maddalen Cave allowed reaching the phreatic passage at the origin of the cold spring, which however also crosses the thermal body in the third sump (S3). Both water bodies are separated by a sharp thermocline. 6 pressure-temperature dataloggers were placed in both water bodies along the thermocline for 6 months. The dataloggers located downstream on either side of the thermocline show at the beginning of flood first a rise of the thermal body, then an invasion of the whole phreatic passage by the cold floodwater, controlled by head pressure changes in the karst aquifer. From observation of these mechanisms, we deduce a hydrodynamic model with a warm plume rising into the cold aquifer, without significant mixing. Such independence of water bodies is explained by the decrease of turbulent rate at the interface, due to the sharp density gradient. The relative absence of mixing does not actually require independent “watertight” routes, both water bodies can thus coexist even in the same conduit. This model locally implies the existence of unknown secondary passages close to the spring, which allow an independent draining of each water body toward separate outlets during low stage. Such type of stratified aquifer linked to density differences is common in coastal karst (Florida, French Calanques…), in the continental evaporite karst (Schlotten of the Harz in Germany, Kungur karst in Ural…), but remains poorly identified in continental carbonate karst areas, mainly because of the difficulty of access. Together with the Mescla spring in French Alpes-Maritimes, the Camou twin springs discharging in the same porch are an outstanding example, allowing a direct study of the stratification and the dynamic of highly contrasted water bodies.","PeriodicalId":56286,"journal":{"name":"International Journal of Speleology","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2022-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47272080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}