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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. ...
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,
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. ...
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 grain shape is the geometrical aspect of grains [16].?
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Featured articles from Cave & Karst Science Journals
Seventeen blind valleys of the Yarrangobilly karst are describes especially with reference to shifting streamsink location and phases of downward incision. A series of measures of them, based partly on ground traverses and partly on contoured maps, is presented and discussed. Standard morphometry of the basins ending in the blind valleys is presented also. These truncated basins are shown to have normal morphometric relationships. Whether a stream sinks or not in the limestone appears generally to relate to the length of limestone to be crossed in relation to full stream or basin length, though basin relief ratio may intervene. The hypothesis that there will be dynamic equilibrium between the dimensions of blind valleys and sinking stream catchments finds only limited support in the data. This is because underground stream capture represents an abnormal event in drainage basin development liable to upset equilibrium relationships and its timing may be adventitious in that development. With a larger population of blind valleys to be analysed, this factor of timing might become subordinate, and a batter predictive model of blind valley volume be derived.
KARST RESEARCHES IN USSR - Karst researches in USSR have obtained a further development during these last years. Numerous regional investigations have been realised, especially in Crimea, Western Caucasus, Podolia, Ural, Central Asia and Southern Siberia. Some works on caves sedimentology have permitted to develop the knowledge on speleogenesis. Interesting studies are performed on speleoclimatology and ice caves (thermo-karst). Several contributions on the modern practical speleology are underlined: speleo-medicine, speleological techniques on steel cables, surveying, morphometry, applied speleology, show caves.
Four areas with different styles of fenglin (tower and cone karst) are investigated using morphometric techniques in the Shuicheng area of Guizhou Province. The karsts were formed in the Neogene and were uplifted during the Quaternary, to present elevations of about 1800 m. Measurements were made of the characteristics of 745 cones using maps and aerial photographs supplemented by field investigations. The karst cones are found to be of almost constant slope angle (45-degrees to 47-degrees) regardless of structure, but with a tendency for slightly lower slopes to occur where the carbonates have impure interbeds. Although generally symmetrical in plan, elongation of both cones and intervening depressions appears controlled by major elements of the structure and the general slope of the topography. Spatial analysis shows the cones to be relatively uniformly distributed in three of the four cases studied. Morphometric evidence points strongly to parallel slope evolution of cones. A model is offered of landscape evolution in which sequential development occurs through stages of karst-tableland with dolines to fencong-depression to fenglin-depression and finally to fenglin-plain. Geological control becomes less influential as this development proceeds, with the smaller and more widely spaced cones of the later stages becoming increasingly symmetrical in form
Successive tectonic phases on limestone massifs are at the origin of a fracturation grid with several pattern dimensions, and linear or organized drain directions. Mechanical reactivations are observed from Oligocene until Plio-Quaternary on a former "pyreneo-provençale" structure (Eocene). Statistical analysis of gallery and fracture directions, cave levels and descent stages (overdeepening) show several erosional stages occurring after the formation of the Antevindobonian erosional surface. The active speleogenesis during Oligocene and Miocene was controlled by tectonics in connection with European rifting and mediterranean opening. In Messinian a short and significant lowering of mediterranean base level (and water table) made drastic erosion and created vertical pits. The horizontal cave level dug during the stabilization phase of Pliocene, now perched over underground rivers, shows a new overdeepening because of glacio-eustatic Quaternary oscillations. Compressive or distensive mechanical reactivations (Upper Miocene, Pliocene, Quaternary) modified the drainage and consequently the cave organization: self-piracy, confluence and diffluence. In the endokarst, the drainage inversion can be detected in late Upper continental Miocene and early Messinian (6,5 Ma), in correlation with the tilting and extension of the continental margin. Five caves in Provence are studied: Sabre, Petit Saint-Cassien, Rampins, Planesselve river, and Tete du Cade networks.
The data of karst ecological study in Mecsek Mountain (South Hungary) can be compared by the analyses in Bükk Mountain and Aggtelek (North Hungary). The western part of Mecsek Mountain is rich in karst forms, the rock base being in strongly fissured Triassic limestone. From a morphometric point of view these dolines are significantly different from those in the karst areas of Bükk and Aggtelek; they are smaller, more shallow and funnel shaped. The amount of 700 mm precipitation per year and increased CO2 production of root systems play an essential role. Soil research studies also support the juvenility of these dolines. Dolines in the Orfü karst plateau are in a natural state, more or less free from anthropogenic influences; however, indirect effect can be shown by the fact that the soil pH is turning sour. This state close to its natural condition is of great value of the landscape, as nowadays it is an important task to conserve the natural conditions of the environment, especially in karst regions. The karst is a highly vulnerable natural system that reacts with great sensitivity to anthropogenic influences, so it requires increased protection; this is why it would be reasonable to include the Orfü karst region in conservation projects.
During Ultima Patagonia project (2000) on Madre de Dios island karst (chile), runoff and erosion characteristics have been measured and followed on the field, to explain the hypertrophy and particularity (profiled shapes) of the marble and limestone karrens. Hydrologic and morphologic measures have been made on a little catchment (100 m2). In this subpolar oceanic context, it appears that evaporation rate on bare karst is low despite the strong wind and consequently runoff activity is particularly strong. These measures are compared to those made on karst tables and dykes originating from differential corrosion, that show moreover the wind part in the development of wind-profiled karrens, a special karst landscape unknown up to now. Surface karst denudation is about 100 mm / ka.
This underground ice work comes in the framework of high-resolution environmental records in underground deposits researches. With this aim, we have chosen the Autrans ice cave to analyse an ice core. In a preliminary research about the ice cave and its working in comparison to climatic variations, we have two informations: there's two types of working, of dynamic from season to season, and the cave morphology is very important for draughts.
ENGLACIAL CAVES OBSERVED BY SPELEOLOGISTS - The speleological investigation of moulins, intraglacial conduits and subglacial tunnels allows to collect informations, which help better to understand the behaviour of the glacier in movement. To find these field data it is necessary at first to conceive how appear and evolve intra- and subglacial cavities. They consist of four types: 1) those opened by meltwater; 2) properly so called crevasses; 3) cavities of volcanic origin; 4) cavities in the lee of bedrock bumps. Directly observable data by the cavers must be always propped up with the time. They concern: 1) the location of cavities and their zone of drainage; 2) the morphology of accessible entrances; 3) the state and the stress of the ice host of cavities; 4) an informed morphometry of investigated voids; 5) level variations and relative age of the trapped waters, and present solid load, the nature and its disposal if necessary. All these data should be represented on plans, profils and cross sections that usually draw up the cavers. Because these documents are easely conveyed and available for consultation by a widened scientific community.
Backward rate of a marble side slope (Island Diego de Almagro, Chilean Patagonia) - Our research group measured the dissolution caused regressive velocity of the marble’s side slope on one of the marble stripes on the island of Diego de Almagro. Using the time of ice melting and the width of rim bordering the edge of the sidewall the velocity of regression is 0,4-0,5 mm per year. This velocity of regression exceeds with an order of magnitude the velocity of denudation caused by dissolution on marble surface. Due to this fact, the marble stripes of the island become narrower to a bigger degree than they become shorter.