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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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Your search for wet (Keyword) returned 211 results for the whole karstbase:
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The origin of the sediments located in the Naracoorte Caves (South Australia) was investigated via the analysis of strontium isotope ratios (87Sr/86Sr), elemental geochemistry, and mineralogy. Sedimentary deposits located in Robertson, Wet, Blanche and several other chambers in Victoria Cave are all variable mixes of fine sand and coarse silts, which display similar and consistent strontium isotope ratios (0.717-0.725). This suggests that over the 400[no-break space]ka time frame that these deposits span there has been minimal variation in the source of the clastic sediments. Increased strontium concentrations for these cave sediments correspond with increasing silt content, yet there is no correlation between 87Sr/86Sr ratios and silt content. This implies that the silt-sized component of the sediments is the main contributor of strontium to the cave sediments. Comparisons of 87Sr/86Sr with regional surficial deposits show a significant correlation between the cave sediments (avg: 0.7228; n = 27), the fine silt lunettes of the Bool Lagoon area (avg: 0.7224; n = 4), the sandy A horizons of the Coonawarra Red Brown Earths (RBEs; avg: 0.726; n = 5), and Holocene age podsolic sand deposits (0.723). These data suggest that there has been substantial flux from this group of deposits to the caves, as would be expected considering prevailing winds. This relationship is further supported by a strong correlation between many trace elements, including Ti, Zr, Ce, and Y; however, variations in clay mineralogy suggest that the fine silt-dominated lunettes and Padthaway RBEs were not significant contributors to the cave deposits. Hence, the detritus entering the caves was more than likely from areas proximal to the cave entrance and was dominated by medium grain-sized materials. Major regional deposits, including the coarser-grained, calcite-rich Bridgewater Formation sands, basalts from the lower SE, Padthaway Horst granites, Gambier limestone, and metamorphics from the Adelaide geosyncline show minimal correlation in 87Sr/86Sr ratios, elemental geochemistry, and mineralogy with the cave sediments, and are discounted as significant sources. In comparison, 87Sr/86Sr ratios for the Coorong silty sands (0.717-0.724), Lower Murray sands (0.727-0.730), and the medium size silt component of the Murray-Darling River system (0.71-0.72), compare favourably with the cave sediments. This relationship is further supported by similarities in elemental chemistry and mineralogy. Thus, much of the strontium-rich silt that is now located in the Naracoorte Cave sediments likely originated from the Murray-Darling basin. Over time, this material has been transported to the SE of South Australia, where it mixed with the medium sand component of the regressive dune ridge sequence, locally derived organic matter, limestone fragments, and fossil material to produce the unique deposits that we see evident in many of the chambers of the Naracoorte Cave system today
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
[Geldloch (1816/6), Dachstein-Rieseneishöhle (1547/17)]
[(1816/14), mit einer Graphik]
[Dachstein-Rieseneishöhle (1547/17), Eisriesenwelt (1511/27), mit Temperaturtabellen]
[Dachstein-Rieseneishöhle (1547/17)]
In this note, which results from a paper published in France, the author defines the "karst system" formed by several successive levels, at the heart of a limestone mass: joints of surface feeding, vertical chimneys, galleries which are alternatively dry and full of water according to the season, a network of continually drowned clefts. He then studies modifications in this system resulting from internal causes, corrosion, filling and sedimentation, concretion. Then he shows how this evolution of the karst system may be modified by general conditions: geology, tectonics, geography with the losses, resurgences and the role of surface formations. The deepening of the river level may create a structure of differing levels in the various karst system, but their positioning is always slower than the streams erosion and it comes about later. In any case, the caves in a dried karst system undergo an evolution on their own. Finally, the author gives the definition of the terms used to explain the evolution in the karst system: "embryonic galleries" in the network of clefts, "young galleries" in the zone which is alternately wet and dry, "mature galleries" where the concretion and the erosion are balanced, "old galleries" where the concretion is becoming more and more important, "dead galleries" where the cave is completely filled by the deposits and concretions. This classification will easily replace the inexact terms of "active galleries" and "fossilized galleries" which are too vague and lead to confusion.
The author has studied the group kiesenwetteri of the genus Speophilus (Col. Catopidae), endemic of Catalogna (Spain). The paper comprises a geographical and geological analysis of the by this group colonised massifs, with a study on the geological isolation of the species and a faunistic study of the 5 actually known forms, one of which new.
Results 1 to 15 of 211
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