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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 consumer is any living thing that is unable to manufacture food from nonliving substances, but depends instead on the energy stored in other living things [23]. see also carnivore; decomposers; food chain; herbivore; omnivore; producers.?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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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 central ebro basin (Keyword) returned 5 results for the whole karstbase:
Le karst du gypse du centre de la dpression de l'Ebre (Espagne), 1990, Soriano, M. A.
THE GYPSUM KARST OF THE CENTER OF THE EBRE BASSIN (SPAIN) - The central Ebro basin was filled with evaporitic deposits (gypsum and limestones) during the Miocene. During the Quaternary, several alluvial terrace and pediment levels were developed and they overlay the gypsum deposits. A large number of karstic landforms developed on gypsum have been found. The most important reason is its high solubility. We have found different types of microlandforms. The most important are Rillenkarren, solution pits and micro etching. There are also small tumuli. They are active at present. We have differentiated three macrolandforms: paleocollapses, depressions and alluvial dolines. The paleocollapses are very narrow and deep. They are filled with quaternary materials. They are not active and were generated in the Middle or Upper Pleistocene. The depressions were developed by the gypsum dissolution, together with topographical and geomorphologic factors. They do not seem to be active nowadays. The alluvial dolines are developed on the terrace and pediment deposits, which overlay gypsum materials. There is basin, well and pan-shaped dolines and they are especially frequent in the T2 terrace level. From the study of aerial photographs of different years, the variations in the number and size of dolines and their density have been determined. Natural factors (lithology and fractures), together with human activities (irrigation) are the principal causes in their development.

Dedolomitization and other early diagenetic processes in Miocene lacustrine deposits, Ebro Basin (Spain), 1999, Arenas C, Zarza Ama, Pardo G,
A variety of meteoric diagenetic features reveal the development of a syngenetic karst on lacustrine deposits of the Ebro Basin. Diagenetic processes that operated on lacustrine laminated and stromatolitic carbonates include the following. (1) A first syndepositional stage with processes such as dolomitization, desiccation and related breccia formation and sulphate precipitation, either as lenticular gypsum crystals or nodules. This stage took place under progressive evaporation due to lake level fall, when the previous carbonate deposits became exposed as a supra-littoral fringe surrounding saline mud flats of adjacent sulphate depositional environments. (2) A second early diagenetic stage in which processes such as sulphate dissolution and collapse brecciation, dedolomitization, calcite spar cementation and silicification occurred as a result of meteoric water input that caused a progressive rise in lake level. Light isotopic compositions (delta(13)C and delta(18)O) of diagenetic calcites, versus heavier compositions in primary laminated and stromatolitic limestones, confirm a meteoric influence. The syngenetic karst is best developed at the boundary between two allostratigraphic units and coincided with one of the extensive stages of sulphate deposition at the end of the Early Miocene. The karst facies occurred in an area that was a low-relief barrier that separated two sites of sulphate deposition during low lake levels, This indicates that the karat development was controlled by topographic changes within the basin and record a shift from arid to wetter climatic conditions, as suggested by the overlying freshwater carbonate deposits. The presence of diagenetic features such as those described in the central Ebro Basin affecting saline lacustrine carbonates is relevant because they can be used as indicators of subaerial exposure periods in terrestrial environments and they also reveal important palaeogeographic and palaeoclimatic events of basinal extent.

Subsidence rates and urban damages in alluvial dolines of the Central Ebro basin (NE Spain), 2002, Soriano M. A. , Simon J. L. ,
In the central Ebro basin, alluvial dolines develop on Quaternary materials overlying Neogene evaporites. This process is very active. Analysing aerial photographs of different years important differences can be observed. Since the 1970s, when the urbanisation of the area took place, karst processes have damaged many buildings and infrastructures. From the dates of construction and the repair of a number of buildings and pavements we calculate subsidence rates (12-120 mm/year). Moreover, we decided to monitor, for around 4 years, three dolines developed on urban areas to determine their subsidence behaviour. A water level device (with an error of 2-3 mm) was utilised for this purpose. The subsidence rates, so obtained, are 64.5, 39 and 21 mm/year, which fit with the previous data from repaired zones

Magnetic prospection as an efficient tool for doline detection: a case study in the central Ebro Basin (northern Spain), 2007, Mochales T. , Pueyo E. L. , Casas A. M. , Soriano M. A. ,
The presence of alluvial dolines in the Ebro Basin causes problems to both agricultural and urban areas. At present, new urbanization of former farming areas requires new tools to detect karst zones and so diminish the hazard linked to collapses. In the surroundings of Zaragoza, dolines (developed mainly on Quaternary alluvial terraces covering a Tertiary gypsum substratum) are commonly filled with alluvial deposits, agricultural soils, urban debris, etc. Measurements of magnetic susceptibility show a remarkable contrast between host rocks and cavity fillings, demonstrating the value of magnetic surveying. A field test was made in a recently collapsed (September 2003) doline filled currently with urban debris. A magnetic survey was carried out following a 130 m2 grid, with 1-10 m spacing between profiles. A proton magnetometer with gradiometer was utilized, and the total field intensity and gradient measurements were taken. The magnetic survey demonstrated a strong anomaly with a dipole defined by more than 650 nT and a gradient of about 100 nT m-1. The 2.5-dimensional (2.5D) modelling of the magnetic anomaly fits well with the known geometrical data. Two other dolines (that are not clearly defined at the surface) were also detected during the survey. These results validate the starting hypothesis and open a new research approach to the problem. The magnetic survey output allows the construction of realistic geological models

Quaternary alluvial sinkholes: Record of environmental conditions of karst development, examples from the Ebro Basin, Spain , 2012, Soriano M. A. , Luzon A. , Yuste A. , Pocovı, A. , Perez A. , Simon J. L. , Gil H.

The central Ebro Basin is an exceptional region for studying karstification through time and under different environmental conditions, as sinkholes have been developing since the Early Pleistocene. Knowledge of active sinkholes is complemented with research on paleosinkholes and contemporary deposits. Sedimentological, mineralogical, geomorphological and structural approaches permit interpretation of the natural environmental conditions that favored karst in the past and the main genetic mechanisms involved. The sedimentary features of Pleistocene terraces indicate that they were deposited by a gravel braided fluvial system characterized by higher water and sediment availability than today, probably related to meltwater flows coming from glaciated source areas, mainly in the Pyrenees. Genesis of paleosinkholes was mainly linked to this high water supply. Some of them acted as small lakes where fine sediments are exceptionally well conserved to give clues about environmental conditions. The neoformation of palygorskite and sepiolite suggests arid to semiarid climatic conditions, in agreement with the idea of cold glacial episodes. During Pleistocene times, development of sinkholes was influenced by tectonics. Currently, the genesis and evolution of numerous sinkholes are also influenced by water supplies from human activities such as irrigation or urbanization, sharply changing the nearly steady state exhibited in the past


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