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Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

Did you know?

That infiltrability is the ease of infiltration [16].?

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KarstBase a bibliography database in karst and cave science.

Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
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 microcosm (Keyword) returned 4 results for the whole karstbase:
MICROBIAL DECOMPOSITION OF ELM AND OAK LEAVES IN A KARST AQUIFER, 1993, Eichem Ac, Dodds Wk, Tate Cm, Edler C,
Dry Chinquapin oak (Quercus macrocarpa) and American elm (Ulmus americana) leaves were placed in four microcosms fed by groundwater springs to monitor changes in dry mass, ash-free dry mass, and microbial activity over a 35-day period. Oxygen microelectrodes were used to measure microbial activity and to estimate millimeter-scale heterogeneity in that activity. Oak leaves lost mass more slowly than elm leaves. Generally, there was a decrease in total dry weight over the first 14 days, after which total dry weight began to increase. However, there were consistent decreases in ash-free dry mass over the entire incubation period, suggesting that the material remaining after initial leaf decomposition trapped inorganic particles. Microbial activity was higher on elm leaves than on oak leaves, with peak activity occurring at 6 and 27 days, respectively. The level of oxygen saturation on the bottom surface of an elm leaf ranged between 0 and 75% within a 30-mm2 area. This spatial heterogeneity in O2 saturation disappeared when the water velocity increased from 0 to 6 cm s-1. Our results suggest that as leaves enter the groundwater, they decompose and provide substrate for microorganisms. The rate of decomposition depends on leaf type, small-scale variations in microbial activity, water velocity, and the length of submersion time. During the initial stages of decomposition, anoxic microzones are formed that could potentially be important to the biogeochemistry of the otherwise oxic aquifer

Karst collapse mechanism and criterion for its stability, 2001, He K. Q. , Liu C. L. , Wang S. J. ,
Karst collapse, caused by natural or artificial abstraction of groundwater, has been a focus of environmental geological problems for its ever-increasing hazardousness. The potential erosion theory and vacuum suction erosion theory, which reveal the origin of karst collapse macroscopically, are popularly accepted. However, a mathematic prediction criterion for karst collapse cannot be established only by these two theories. From a new perspective, this paper attempts to explain the microcosmic mechanism of karst collapse on the basis of these two theories. When the shear stress surpasses the shear strength of soil, a certain point or a certain plane in the unconsolidated soil covering karst caves will fail under the mechanical effects of water and air as well as its load-pressure, and with the increase of damaged points, a breaking plane appears and the soil on karst caves is completely damaged; as a result, the karst ground collapses. On the basis of the Mohr-Coulomb failure theory and previous studies, the paper presents a prediction criterion of karst collapse. Finally, by taking, for example, nine typical cases of collapse caused by pumping tests in Guizhou, the paper gives the calculation process of the model and proves its reliability

Karst collapse related to over-pumping and a criterion for its stability, 2003, He K. Q. , Liu C. L. , Wang S. J. ,
Karst collapse, caused by natural or artificial abstraction of groundwater, has been an environmental geological problem. The origin of karst collapse has been described by the potential erosion theory and the vacuum absorption erosion theory. However, a mathematical prediction criterion for karst collapse cannot be established by these two theories. This paper, from a new perspective, attempts to explain the microcosmic mechanism of karst collapse on the basis of these two theories. At a certain point in the unconsolidated soil covered on karst caves, when shearing stress surpasses shear strength of the soil, it fails under the mechanic effects of water and gas as well as gravity pressure. With an increase in damage points, a break plane appears and the soil overlying the karst caves is completely damaged and, thus, the ground surface collapses. On the basis of Mohr-Coulomb damage theory and previous studies, a prediction criterion of karst collapse is presented. An example displays the calculating process of the model and proves its reliability by analyzing nine typical collapses caused by a pumping test in Guizhou Province, China

La Voragine di piano Macchi - Under �No man's land�, 2012, Potleca, Michele

Mount Pal Piccolo overlooks the pass of Monte Croce Carnico (Friuli Venezia Giulia - Udine) and is located in an interesting and troubled area of the Carnic Alps on the border between Italy and Austria. During World War One (1915–1918) this place witnessed bitter fightings, but nowdays this place lies in peace and the only witness of the past tragedies is an outdoor museum. A place where, walking along the trail of the Alta via Carnica, one remains fascinated by the variety and beauty of the sorrounding landscapes. Geologically speaking, it is a complex area made of tormented ancient limestone rocks. It is within this microcosm that we discovered and mapped a kilometer of new galleries belonging to an old chasm “Voragine del Piano Macchi”, which for decades was thought to have vanished. This old chasm opens in the middle of what in 1915-1918 was the “no man's land” between the barbedwired Italian and Austro-Hungarian front lines…… 160 pages - More than 120 color photos - Historical and geological references - The speleological history of the area - Plan and section of the cave - Diagrams of development - Description of the cave - Images and historical maps - Geological map - Diary of exploration


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