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Featured articles from Cave & Karst Science Journals
Characterization of minothems at Libiola (NW Italy): morphological, mineralogical, and geochemical study, Carbone Cristina; Dinelli Enrico; De Waele Jo
Chemistry and Karst, White, William B.
The karst paradigm: changes, trends and perspectives, Klimchouk, Alexander
Long-term erosion rate measurements in gypsum caves of Sorbas (SE Spain) by the Micro-Erosion Meter method, Sanna, Laura; De Waele, Jo; Calaforra, José Maria; Forti, Paolo
The use of damaged speleothems and in situ fault displacement monitoring to characterise active tectonic structures: an example from Zapadni Cave, Czech Republic , Briestensky, Milos; Stemberk, Josef; Rowberry, Matt D.;
Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Recent research in Europe, Africa, and Southeast Asia suggests that we can no longer assume a direct and exclusive link between anatomically modern humans and behavioral modernity (the `human revolution'), and assume that the presence of either one implies the presence of the other: discussions of the emergence of cultural complexity have to proceed with greater scrutiny of the evidence on a site-by-site basis to establish secure associations between the archaeology present there and the hominins who created it. This paper presents one such case study: Niah Cave in Sarawak on the island of Borneo, famous for the discovery in 1958 in the West Mouth of the Great Cave of a modern human skull, the `Deep Skull,' controversially associated with radiocarbon dates of ca. 40,000 years before the present. A new chronostratigraphy has been developed through a re-investigation of the lithostratigraphy left by the earlier excavations, AMS-dating using three different comparative pre-treatments including ABOX of charcoal, and U-series using the Diffusion-Absorption model applied to fragments of bones from the Deep Skull itself. Stratigraphic reasons for earlier uncertainties about the antiquity of the skull are examined, and it is shown not to be an `intrusive' artifact. It was probably excavated from fluvial-pond-desiccation deposits that accumulated episodically in a shallow basin immediately behind the cave entrance lip, in a climate that ranged from times of comparative aridity with complete desiccation, to episodes of greater surface wetness, changes attributed to regional climatic fluctuations. Vegetation outside the cave varied significantly over time, including wet lowland forest, montane forest, savannah, and grassland. The new dates and the lithostratigraphy relate the Deep Skull to evidence of episodes of human activity that range in date from ca. 46,000 to ca. 34,000 years ago. Initial investigations of sediment scorching, pollen, palynomorphs, phytoliths, plant macrofossils, and starch grains recovered from existing exposures, and of vertebrates from the current and the earlier excavations, suggest that human foraging during these times was marked by habitat-tailored hunting technologies, the collection and processing of toxic plants for consumption, and, perhaps, the use of fire at some forest-edges. The Niah evidence demonstrates the sophisticated nature of the subsistence behavior developed by modern humans to exploit the tropical environments that they encountered in Southeast Asia, including rainforest
Unusual speleothems resembling giant mushrooms occur in Cueva Grande de Santa
Catalina, Cuba. Although these mineral buildups are considered a natural heritage, their
composition and formation mechanism remain poorly understood. Here we characterize
their morphology and mineralogy and present a model for their genesis. We propose that
the mushrooms, which are mainly comprised of calcite and aragonite, formed during four
different phases within an evolving cave environment. The stipe of the mushroom is an
assemblage of three well-known speleothems: a stalagmite surrounded by calcite rafts
that were subsequently encrusted by cave clouds (mammillaries). More peculiar is the
cap of the mushroom, which is morphologically similar to cerebroid stromatolites and
thrombolites of microbial origin occurring in marine environments. Scanning electron
microscopy (SEM) investigations of this last unit revealed the presence of fossilized
extracellular polymeric substances (EPS)—the constituents of biofilms and microbial
mats. These organic microstructures are mineralized with Ca-carbonate, suggesting that
the mushroom cap formed through a microbially-influenced mineralization process. The
existence of cerebroid Ca-carbonate buildups forming in dark caves (i.e., in the absence
of phototrophs) has interesting implications for the study of fossil microbialites preserved
in ancient rocks, which are today considered as one of the earliest evidence for life on
Earth.
Sulfate reducing bacteria (SRB) have existed throughout much of Earth's history and remain major contributors to carbon cycling in modern systems. Despite their importance, misconceptions about SRB are prevalent. In particular, SRB are commonly thought to lack oxygen tolerance and to exist only in anoxic environments. Through the last two decades, researchers have discovered that SRB can, in fact, tolerate and even respire oxygen. Investigations of microbial mat systems have demonstrated that SRB are both abundant and active in the oxic zones of mats. Additionally, SRB have been found to be highly active in the lithified zones of microbial mats, suggesting a connection between sulfate reduction and mat lithification. In the present paper, we review recent research on SRB distribution and present new preliminary findings on both the diversity and distribution of [delta]-proteobacterial SRB in lithifying and non-lithifying microbial mat systems. These preliminary findings indicate the unexplored diversity of SRB in a microbial mat system and demonstrate the close microspatial association of SRB and cyanobacteria in the oxic zone of the mat. Possible mechanisms and further studies to elucidate mechanisms for carbonate precipitation via sulfate reduction are also discussed
Eight breeding Caves of Miniopterus schreibersi (Kuhl) are described from South Australia, Victoria, New South Wales and Southern Queensland, in terms of their structure, the location of nursery areas at which juveniles are deposited after birth, and their physical environments. Maternity colonies are found at these caves through spring, summer and early autumn. Established colonies range from about 15,000 to 200,000 bats at peak size. These individuals are predominantly adult females and their young. Adult males are conspicuous only at the single South Australian breeding cave. Births occur from approximately the beginning of December to mid-January at all colonies except that in South Australia, where a birth period is evident between mid-October to late-November. Artificial warming, as a consequence of bat activity, appears to be characteristic of these Miniopterus schreibersi breeding caves. It is suggested that this may have functional significance in facilitating adequate development of juveniles, and that the habit could be a reflection of the tropical ancestry of this species.
The temperature and relative humidity preferences and tolerances of two Texas species of cave-adapted millipedes, Cambala speobia (Chamberlin) and Speodesmus bicornourus Causey, were studied. Both species showed gross preferences when tested in gradient chambers for temperatures and relative humidities approximating those of their cave environments. But C. speobia, the less adapted species morphologically, was the more selective of the two species for such conditions. S. bicornourus was far less tolerant of elevated temperatures and reduced relative humidities than was C. speobia. Discussed is a possible reason why a terrestrial troglobite like S. bicornourus would combine intolerance with a lessened ability to perceive those factors to which it is intolerant. Discussed also are the possible causes of the present distribution of Cambala and Speodesmus in the caves of central Texas.
The temperature and relative humidity preferences and tolerances of two Texas species of cave-adapted millipedes, Cambala speobia (Chamberlin) and Speodesmus bicornourus Causey, were studied. Both species showed gross preferences when tested in gradient chambers for temperatures and relative humidities approximating those of their cave environments. But C. speobia, the less adapted species morphologically, was the more selective of the two species for such conditions. S. bicornourus was far less tolerant of elevated temperatures and reduced relative humidities than was C. speobia. Discussed is a possible reason why a terrestrial troglobite like S. bicornourus would combine intolerance with a lessened ability to perceive those factors to which it is intolerant. Discussed also are the possible causes of the present distribution of Cambala and Speodesmus in the caves of central Texas.
The feeding responses of salamander larvae (Gyrinophilus porphyriticus) from caves in the Powell Valley in Virginia were investigated in the laboratory. The larvae locate prey by mechanoreception and capture the prey by a rapid sucking action, much like cave-limited salamanders do. Feeding success is greater with the isopod Asellus recurvatus (about 90 per cent) than with the amphipod Crangonyx antennatus (about 50 per cent), and this largely accounts for the higher frequency of A. recurvatus taken in choice experiments. G. porphyriticus readily ingested the unfamiliar isopod Lirceus usdagalun, but it took four weeks before it was digested as well. Small larvae tend to take small prey and large larvae take both large and small prey. Occasionally, larvae lunged at prey, which was usually unsuccessful. This behaviour seems to be a holdover from an evolutionary history in epigean environments where vision could be used to locate prey.
The feeding responses of salamander larvae (Gyrinophilus porphyriticus) from caves in the Powell Valley in Virginia were investigated in the laboratory. The larvae locate prey by mechanoreception and capture the prey by a rapid sucking action, much like cave-limited salamanders do. Feeding success is greater with the isopod Asellus recurvatus (about 90 per cent) than with the amphipod Crangonyx antennatus (about 50 per cent), and this largely accounts for the higher frequency of A. recurvatus taken in choice experiments. G. porphyriticus readily ingested the unfamiliar isopod Lirceus usdagalun, but it took four weeks before it was digested as well. Small larvae tend to take small prey and large larvae take both large and small prey. Occasionally, larvae lunged at prey, which was usually unsuccessful. This behaviour seems to be a holdover from an evolutionary history in epigean environments where vision could be used to locate prey.
1) Nearly two hundred species of troglobites are known from the groundwaters of Japan. Most of these troglobiontic species, sixteen of seventy-seven genera, and what is more, four of fortyseven families are endemic to Japan. Uchidastygacaridae, Nipponacaridae, and Kantacaridae are endemic acaridan families of Japan. The coleopterous family, Phreatodytidae, is alto endemic to Japan. 2) Though studies on Protozoa, Turbellaria, Annelida, Aschelminthes, and Ostracoda, etc. remain sparse, the interstitial fauna is actively investigated recently and many specimens of Bathynellacea, Ingolfiella, Bogidiella, Microcerberus, Pseudovermis (Opisthobranchia), and Nerillidae, etc. have been collected from freshwater and marine environments. 3) None of the troglobites is known to be directly detrimental to human health and most of them have been collected from well-waters which are regarded as chemically clean in many cases, but they have also been obtained occasionally from bacteriologically contaminated well-waters. 4) Ecological and taxonomic knowledge, of even the limited amount which we possess at present, has enabled us to utilize various animals which occur in well-waters as biological indicators of well-water pollution and to have some insight as to the origin of the pollution.
SynopsisThe four major different types of water -- magmatic, metamorphic, sea water and/or connate, and meteoric water -- have characteristic hydrogen (D/H) and oxygen (18O/16O) isotope ratios. Applied to the analysis of isotopic data on hydrothermal minerals, fluid inclusions and waters from active geothermal systems, these ratios indicate that waters of several origins are involved with ore deposition in the volcanic and epizonal intrusive environment. Water of a single origin dominates main-stage mineralization in some deposits: magmatic -- Casapalca, Peru (Ag-Pb-Zn-Cu); meteoric -- Butte, Montana (Cu-Zn-Mn), epithermal deposits, e.g. Goldfield, Tonopah, Nevada (Ag-Au), Pachuca, Mexico (Ag-Au), San Juan Mountains District, Colorado (Ag-Au-Pb-Zn); sea water -- Troodos, Cyprus (Fe-Cu), Kuroko, Japan (Fe-Cu-Pb-Zn). Solutions of more than one origin are important in certain deposits (magmatic and meteoric -- porphyry copper and molybdenum deposits) and are present in many. In the porphyry Cu-Mo deposits the initial major ore transportation and alteration processes (K-feldspar-biotite alteration) are magmatic-hydrothermal events that occur at 750-500{degrees}C. These fluids are typically highly saline Na-K-Ca-Cl-rich brines (more than 15 wt % equivalent NaCl). The convecting meteoric-hydrothermal system that develops in the surrounding country rocks with relatively low integrated water/rock ratios (less than 0.5 atom % oxygen) subsequently collapses in on a waning magmatic-hydrothermal system at about 350-200{degrees}C. These fluids generally have moderate to low salinities (less than 15 wt % equivalent NaCl). Differences among these deposits are probably in part related to variations in the relative importance of the meteoric-hydrothermal versus the magmatic-hydrothermal events. The sulphur comes from the intrusion and possibly also from the country rocks. Deposits in which meteoric or sea water is the dominant constituent of the hydrothermal fluids come from epizonal intrusive and sub-oceanic environments where the volcanic country rocks are fractured or well jointed and highly permeable. Integrated water/rock ratios are typically high, with minimum values of 0.5 or higher (atom % oxygen) -- the magmatic water contribution is often drowned out'. Salinities are low to very low (less than 10 wt % equivalent NaCl), and temperatures are usually in the range 350-150{degrees}C. The intrusion supplies the energy to drive the large-scale convective circulation system. The sulphur comes from the intrusion, the country rocks and/or the sea water. Argillic alteration, which occurs to depths of several hundred metres, generated during supergene weathering in many of these deposits is isotopically distinguishable from hydrothermal clays
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