International Journal of Speleology最新文献

{"title":"Mid- to Late-Miocene hypogene speleogenesis tied to the tectonic history of the central Basin and Range province, USA","authors":"L. Hose, V. Polyak, Harvey DuChene, J. D. Powell, L. Melim, Gretchen M. Baker, Donald Davis, Y. Asmerom","doi":"10.5038/1827-806x.53.2.2507","DOIUrl":"https://doi.org/10.5038/1827-806x.53.2.2507","url":null,"abstract":"Twenty-five caves displaying evidence of hypogene speleogenesis in White Pine County, Nevada, were studied between May 2022 and October 2023. Results demonstrate that the central Basin and Range Province is a major hypogenic cave region with speleogenesis dating back to the Middle Miocene. The U-Pb radiometric dates of cave mammillaries obtained so far cover a wide span of time, ranging between 14 Ma to 2 Ma. Tectonic shearing along the Snake Range Décollement up to about 22 Ma probably brackets the maximum age of speleogenesis. Thus, speleogenesis began between 22-14 Ma, which predates most of the Basin and Range extensional tectonism of the Late Miocene. Robust dates for the common mammillaries in the region have been hard to obtain mostly due to Pb contamination. There are elevated levels of Pb throughout the area, likely due to mineralized fluids associated with the décollement. While 11 mammillary samples (from 10 caves) have been assessed for U-Pb dating viability, five contained too much Pb for analysis. Hypogenic features in these caves include mammillaries, tilted folia, bubble trails, cupolas, ceiling vents/tubes, floor vents, acid lake basins, pseudoscallops (cusps), and boneyard (megacusps). A common and newly identified feature of these caves is extensive secondary deposits of a complex mixture with silt-sized calcite and quartz grains. Some quartz grains have calcite overgrowths, suggesting authigenic growth. We named these lithified, and very porous, deposits “calc-siltite”. Sulfuric acid speleogenesis (SAS) has been clearly demonstrated in only one cave, Lehman Caves, but is strongly suspected in at least four other study sites (Old Mans, Cathedral, #041709-NS-012, and #LC01 caves). However, the great antiquity of these hypogenic caves means that they have probably experienced climatic and surface geomorphologic changes resulting in extensive alterations by epigenic groundwater. The evidence specific to demonstrating SAS processes may have been removed or covered by later epigenic activities.","PeriodicalId":508425,"journal":{"name":"International Journal of Speleology","volume":"2 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141839055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Constraining the evolutionary stages of a hypogene karst system by combining morphological, geochemical and geochronological data - the example of carbonate breccia-hosted Melnička Peštera","authors":"M. Temovski, Zsófia Ruszkiczay-Rüdiger, K. Molnár, László Rinyu, Alexander Wieser, Oscar Marchhart, László Palcsu","doi":"10.5038/1827-806x.53.2.2509","DOIUrl":"https://doi.org/10.5038/1827-806x.53.2.2509","url":null,"abstract":"A combination of morphological observations, geochemical data from calcite minerals and geochronology by burial age dating and U-series is used to constrain the geological and geomorphological setting and the evolutionary stages of a hypogene karst system. This methodological suit is applied to Melnička Peštera, a horizontal cave developed in carbonate breccia overlying dolomite marble in Melnica locality (N. Macedonia), where hydrothermal karst development occurred in both dolomite and calcite marble. The passage morphology of the cave, having a reverse triangle, Laughöhle cross-sections, suggests development near the water table by slowly moving waters. Calcite crusts are found throughout the cave, and based on their relationship to passage morphology, appear to pre-date main horizontal passage formation. Their carbonate stable and clumped isotope and fluid inclusion noble gas compositions indicate cooling of the hydrothermal system with an increased contribution of shallower groundwater. U-series data suggests Early Pleistocene deposition of the calcite crusts. Water table notches and convectional features carved into breccia bedrock and calcite crusts point to subsequent development at and above the water table by condensation corrosion. The solutional aggressiveness near the water table was likely related to CO2, that previously degassed from the deeper parts of the system where calcite was depositing, and redissolved in the cooler, shallower waters. Due to poor connection with the surface, the cave air above the water table likely had high pCO2, that further helped to maintain aggressiveness of the groundwater at the water-air contact, and boosted condensation corrosion above it, preventing deposition of related secondary calcite minerals. The cave-hosting carbonate breccia deposited as an alluvial fan filling up a paleovalley cut into Upper Miocene sediments. Cosmogenic nuclide burial age dating of quartz fragments confirms Early Pliocene age for the breccia, and constrains the paleovalley incision to Late Miocene, likely related to base level lowering caused by the Messinian Salinity Crisis.","PeriodicalId":508425,"journal":{"name":"International Journal of Speleology","volume":"29 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141847479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Revealing the ongoing speleogenetic processes in an underwater cave through the application of natural radionuclides and stable isotopes: case study from the hypogene Buda Thermal Karst","authors":"A. Erőss, Katalin Hegedűs-Csondo, Petra Kovács-Bodor, D. Szieberth, Ákos Horváth, G. Czuppon, Andrea Mindszenty, S. Leél-Őssy, J. Mádl-Szőnyi","doi":"10.5038/1827-806x.53.2.2510","DOIUrl":"https://doi.org/10.5038/1827-806x.53.2.2510","url":null,"abstract":"The underwater Molnár János Cave in the hypogene Buda Thermal Karst system (Budapest, Hungary) provides a unique site to study the effects of flowing groundwater and the interplay of fluids of different origin. The aim of the present study is to characterize the groundwater in different parts of the cave with temporal resolution, hence describe the recent speleogenetic processes within the cave. This study uses natural radioisotopes (uranium, radium, and radon) besides stable isotope ratios of oxygen and hydrogen to identify the different fluid components. The results show that the majority of the cave is situated in the flow path of the intermediate flow system, discharging in the Boltív Spring. Thus, the dominant recent speleogenetic processes are connected to this lukewarm groundwater. In contrast to previous views, typical hypogene processes, such as mixing corrosion involving thermal waters, are restricted to a narrower area in the cave, to the contact zone of lukewarm waters and the warmer upper water layer around the largest partially air-filled chamber (Kessler Hall). The warmer water layer is the result of free convection. In the air-filled chambers condensation-corrosion might be active. However, its effect is limited to the largest room (Kessler Hall), as it is open to surface conditions. More active mixing corrosion probably occurs deeper, in the area of the Northeastern Margin Fault, which is indicated by the radon content in the Boltív Spring. Regarding the temporal processes, the main driving force can be linked to the water level fluctuations of the Danube, which regulates the discharge of the regional flow-related thermal water upwelling, thus affecting the mixing ratio of the lukewarm waters transported by the intermediate flow systems and the thermal waters, representing the regional flow path, including basinal components.","PeriodicalId":508425,"journal":{"name":"International Journal of Speleology","volume":"25 S2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141848641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"CO2 hypogene speleogenesis in an endogenic travertine system, Mesa del Oro, New Mexico, USA","authors":"V. Polyak, Jeffrey Forbes, Michael N. Spilde, Paula Provencio, John Cochran, Y. Asmerom","doi":"10.5038/1827-806x.53.2.2502","DOIUrl":"https://doi.org/10.5038/1827-806x.53.2.2502","url":null,"abstract":"The Mesa del Oro travertine, deposited by upwelling CO2-rich spring waters, is a large and thick mantle of calcite overlying soft Triassic Chinle Formation mudstones in western central New Mexico, USA. The travertine contains a system of small caves known as the Pronoun Cave Complex. Whut Cave is the largest known cave in the complex. While the travertine hydrologic system is no longer active, there is ample evidence that Whut Cave was formed by hypogene speleogenesis. The Whut Cave entrance is a small roughly circular shaft that descends ~four meters and intersects a linear fissure-controlled passage. Mn-oxide was once mined below the entrance, leaving a five-meter-deep pit that represents the path of upwelling waters that were likely charged with CO2 and supersaturated with CaCO3 once reaching the surface. The roomiest part of the cave is immediately adjacent to the entrance, defining where most of the upwelling of groundwater and gases took place. Gypsum and other sulfates were only noted microscopically. A sample of travertine at the surface near the entrance yielded a uranium-series age beyond the limit of the method and a δ234U age of 735 ± 109 ka BP (before present). A piece of breccia vein in the mine dump associated with the Mn-oxide ore, and a rill of a drape-like crust on the cave wall, both interpreted to be products of hypogene speleogenesis and representing the oldest speleogenetic material, yielded δ234U ages of 848 ± 110 and 723 ± 109 ka BP. Altogether, materials interpreted to be speleogenetic yielded ages of ~900 – 300 ka BP. Although the cave is dry and hydrologically inactive today, cave development by CO2 hypogene speleogenesis was coeval with endogenic travertine deposition and nearby volcanism. Our interpretation suggests that all these events are linked.","PeriodicalId":508425,"journal":{"name":"International Journal of Speleology","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141850662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rates of diagenesis of tropical insectivorous bat guano accumulations: implications for potential paleoenvironmental reconstruction","authors":"D. McFarlane, Joyce Lundberg","doi":"10.5038/1827-806x.53.1.2494","DOIUrl":"https://doi.org/10.5038/1827-806x.53.1.2494","url":null,"abstract":"Cave guano deposits are increasingly being recognized as valuable repositories of paleo-climatic and paleo-environmental information. However, that value is constrained by rates of guano decomposition, and these rates have not been previously well-studied. Here we show that field and laboratory studies of deep insectivorous bat guano sequences in the caves of Borneo demonstrate the extreme dependence of decomposition rate on guano water content. Under tropical conditions, moist guanos exhibit decomposition coefficients (k) values of ~ 0.01, implying the loss of most of the organic content on decadal timescales. Under similar temperatures but drier conditions, k values drop to ~3 x 10-6, permitting significant organic (chitin) content to persist for tens of thousands of years. One of the implications of these findings for paleo-environmental records older than the limit of carbon dating is that a value for k can be calculated based on a single carbon date, which then allows an estimate of likely age at base of deposit.","PeriodicalId":508425,"journal":{"name":"International Journal of Speleology","volume":"27 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140464935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Subaqueous carbonate speleothems as paleotemperature archives – clumped isotope thermometry and stable isotope compositions of inclusion-hosted water","authors":"A. Demény, Ágnes Berentés, László Rinyu, I. Kovács, G. Surányi, Magdolna Virág","doi":"10.5038/1827-806x.53.1.2480","DOIUrl":"https://doi.org/10.5038/1827-806x.53.1.2480","url":null,"abstract":"Clumped isotope measurements of carbonates and stable isotope analyses of water trapped in fluid inclusions are both promising techniques to determine carbonate formation temperatures. Cave-hosted carbonate deposits (speleothems) are excellent targets for such studies, but kinetic fractionations and diagenetic influences frequently deteriorate the temperature data obtained from these methods. However, subaqueous carbonate deposits may provide reliable data, as kinetic fractionations are less significant in underwater environments. In this study, subaqueous speleothems, whose formation temperatures were directly measured in the water, were investigated. Additionally, temperatures calculated from the oxygen isotope fractionations between calcite and fluid inclusion-hosted water were compared with clumped isotope temperatures obtained for subaqueous carbonate formations in cave-hosted lakes. The clumped isotope temperatures fit the measured and calculated fluid inclusion temperatures within the analytical precisions. Carbonate deposits formed at elevated temperatures (~50°C or above) may undergo post-formational calcite-water oxygen isotope exchange, altering the composition of the inclusion-hosted water. In contrast, subaqueous speleothems formed at about 20-25°C appear to preserve the primary isotopic compositions. Our study shows that subaqueous carbonate speleothems are useful targets for clumped isotope and inclusion water analyses, making them valuable paleotemperature archives.","PeriodicalId":508425,"journal":{"name":"International Journal of Speleology","volume":"46 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140465765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}