This research provides bihourly temperature and relative humidity data from ten measuring locations in eight caves from one of the largest contiguous arid karst areas in the world, the Nullarbor ...Plain in south Australia. The current data span the period from November 2019 to March 2021, and represent the first continuous published monitoring of the subterranean features in this area. The data were recorded using ten TGP-4500 Tinytag Plus 2 self-contained temperature (resolution ±0.01 °C or better with a reading range from −25 °C to +85 °C) and relative humidity (resolution ±3.0% or better with a reading range from 0% to 100%) data loggers and are available in the form of a spreadsheet. The text also describes reported (but only occasional) visits to the caves, so that the data for those particular days and/or hours can be treated as anthropogenically influenced. The data have great potential to provide insight into underground karst processes, air mass movements, hydrogeology, speleothems and (palaeo)climate, current climatic changes, and biology.
Large deep caves with little relation to surface topography are distinctive karst features on the Nullarbor Plain of Australia. The presence of gypsum deposits and chemoautotrophic bacteria within ...the caves have been suggested as evidence for cave formation and (or) enlargement via sulfuric acid speleogenesis. To test this hypothesis, the stable sulfur isotope compositions (634S) of both cave gypsum and surface gypsum were measured. Analyses yielded relatively high, positive 634S values from both cave gypsum and surface gypsum, arguing against gypsum genesis via microbial chemoautotrophy, and more broadly, sulfuric acid speleogenesis. Instead, the gypsum is interpreted as forming via evaporation of seawater during the Quaternary.
The Slovenian climate has undergone significant fluctuations, and an understanding of the past climate is necessary to improve models and recognise long-term patterns. The cryosphere environment, ...such as ice core samples, provides valuable palaeoclimate data. Palynology and dendroclimatology are also effective ways to study long-term changes in vegetation and reconstruct past climates using pollen and tree proxies. Sediment cores from various locations in Slovenia have been studied to understand past environmental changes. Borehole temperature profiles as well as historical records were also used to reconstruct past climate conditions. Studies have shown specific periods when climatic changes likely played a major role, but a complete timeline of the Slovenian climate throughout the Holocene has not yet been fully developed.
The development of the tourist trail in the side passage Rov Novih Podpisov of Postojna Cave in 2001 exposed an over four metres thick sedimentary succession characterised by horizontal flowstone ...layers intercalated between fine-grained fluvial sediments, and gravel deposits that record past environmental changes. The time of the flowstone deposition was determined by radiocarbon and uranium-thorium dating techniques. The results yielded three distinctive age groups of flowstone facies of 33 ka, 103 ka and 153 ka. These results also indicate that flowstone deposition has not been limited solely to periods of warm climate, which suggests that environmental conditions during glacial periods in south-western Slovenia supported flowstone deposition.
The Triglav Glacier in the Julian Alps and the Skuta Glacier in the Kamnik-Savinja Alps are among the south-easternmost glaciers in the Alps. Historical data show that ice masses are undergoing mass ...loss as the overall climate warms. Glacier ice and cave ice contain a wealth of paleoclimatic information, and rapid sampling is needed if any such information is to be saved before the ice is completely melted. We present the first comprehensive geochemical and water isotope data from glacier ice, meltwater, spring water, and cave ice in the Mount Triglav area and glacier ice from the Skuta Glacier. The samples primarily reflect the initial precipitation signal that has been greatly modified by the input of local CaCO3-rich dust with lesser amounts of marine aerosol and vegetation debris.
Karst on the Nullarbor Plain has been studied and described in detail in the past, but it lacked the determination of the karst discharge and palaeo-watertable levels that would explain the ...palaeohydrological regime in this area. This study explores the existence of previously unrecognised features in this area – karst pocket valleys – and gives a review on pocket valleys worldwide. Initial GIS analyses were followed up by detailed field work, sampling, mapping and measuring of morphological, geological, and hydrological characteristics of representative valleys on the Wylie and Hampton scarps of the Nullarbor Plain. Rock and sand samples were examined for mineralogy, texture and grain size, and a U–Pb dating of a speleothem from a cave within a pocket valley enabled the establishment of a time frame of the pocket valleys formation and its palaeoenvironmental implications. The pocket valleys document the hydrological evolution of the Nullarbor karst system and the Neogene–Pleistocene palaeoclimatic evolution of the southern hemisphere. A review of pocket valleys in different climatic and geological settings suggests that their basic characteristics remain the same, and their often overlooked utility as environmental indicators can be used for further palaeoenvironmental studies. The main period of intensive karstification and widening of hydrologically active underground conduits is placed into the wetter climates of the Pliocene epoch. Subsequent drier climates and lowering of the watertable that followed sea-level retreat in the Quaternary resulted in formation of the pocket valleys (gravitational undermining, slumping, exudation and collapse), which, combined with periodic heavy rainfall events and discharge due to impeded drainage, caused the retreat of the pocket valleys from the edge of escarpments.
•Karst pocket valleys are identified on limestone escarpments on the Nullarbor Plain.•Karst pocket valleys are valuable palaeoenvironmental indicators.•Palaeo karst discharge is identified by the pocket valley location.•U-Pb flowstone dating correlates with the globally wetter Pliocene climate.
a loose/broken stalagmite containing small fragments of cemented bones were collected from the Postojna Cave to investigate whether deoxyribonucleic acid (DNA) can be determined. The study is ...complemented by the Fourier-transform infrared spectroscopy - attenuated total reflectance (FTIR-ATR) analysis in order to determine the alteration of the bones and to test whether this analysis can be used as an indicator of possible DNA preservation. In addition, geochemical analyses were conducted in order to determine whether the associated flowstone/stalagmite is suitable for elucidating the timing of bone thanatocoenosis and further palaeoenvironmental analyses. The organic matter (collagen) is poorly preserved. However, we succeeded in amplifying a 94 bp long fragment of the cytochrome b (Cyt b) gene of mitochondrial DNA (mtDNA) in polymerase chain reaction (PCR) for one sample, and in sequencing the amto that of the Cyt b of the cave bear (Ursus deningeri or Ursus spelaeus sensu lato). The uranium-thorium dating of the speleothem covering the bones revealed its thanatocoenosis occurred prior to 55 ka, most likely in the late marine isotope stage 4 or early marine isotope stage 3. High porosity and recrystallisation of the flowstone/stalagmite at this part of the cave prevent high-resolution palaeoclimatic interpretation; however, low-resolution stable isotope geochemistry suggests a steppe-like environment during the subsequent growth of the speleothem.
Cave ice samples collected within karstic terrain have major ion and nutrient concentrations showing that the ice originates from local precipitation modified by the addition of Ca2+ and HCO3− from ...the dissolution of the local bedrock. Isotopic profiles of Paradana Cave ice are similar to those described in other ice caves in central and eastern Europe, where the profiles are developed through the freezing of cave pool or “lake” waters from the top downward during the onset of the cold portion of the year. Stable isotope data suggest future studies may yield a long-term paleo-environmental record for this location.
The Pleistocene Bridgewater Formation is well exposed at Cape Bridgewater and surrounding areas in south-western Victoria, where field studies, mineralogical and isotopic analyses and OSL dating have ...shown that it can be divided into three members, here named (in stratigraphic order) the Descartes Bay, Bats Ridge and Duquesne members. Each member consists of aeolian calcarenite deposited as a coastal dune, that was karstified (with solution pipe development) and then overlain by a red or purple palaeosol. The aeolianites were deposited in three distinct phases corresponding to interglacials MIS 11, MIS 9 and MIS 7, respectively, when the shoreline was near present sea level. Karstification occurred as a result of the high effective precipitation characteristic of the transition between interglacial and glacial periods, followed by aeolian dust accession and palaeosol formation during the drier, windier glacial climates. Comparison with the coeval Tamala Limestone in south-western Western Australia shows simultaneous changes in palaeoclimate: high effective precipitation during the transition from MIS 11 to MIS 10, and a relatively dry transition from MIS 9 to MIS 8. Abundant rainfall during MIS 5 caused extensive limestone dissolution (solution pipes in Victoria, pinnacles in Western Australia) and the resulting quartz sand residue was redeposited during MIS 2-4.
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