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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. ...

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That bedding-plane parting is see bedding plane and parting.?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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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 arid areas (Keyword) returned 10 results for the whole karstbase:
Recharge of Phreatic Aquifers in (Semi-)Arid Areas, ,
Groundwater use is of fundamental importance to meet the rapidly expanding urban, industrial and agricultural water requirements in (semi) arid areas. Quantifying the current rate of groundwater recharge and define its variability in space and time are thus prerequesites for efficient groundwater resource managment in these regions, where such resources are often the key to economic development. Attention focuses on recharge of phreatic aquifers, often the most readily-available and affordable source of water in (semi) arid regions. These aquifers are also the most susceptible to contamination, with the recharge rate determining their level of vulnerability. (Semi) arid zone recharge can be highly variable, the greater the aridity, the smaller and potentially more variable the natural flux. Its determination is an iterative process, involving progressive data collection and resource evaluation; there is also a need to use more than one technique to verify results. Direct, localised and indirect recharge mechanisms from a spectrum of known sources are addressed in the framework of recharge from precipitation, intermittant flow and permanent water bodies. The approach taken for each of these reflects the nature and current understanding of the processes involved. The volume also reviews current recharge estimation challenges, outlines recent developments and offers guidance for potential solutions.

La mise en exploitation des aquifres karstiques : quelques exemples algriens, 1987, Collignon, B
EXPLOITATION OF KARSTIC AQUIFERS IN ALGERIA - Some difficulties are specific of the karstic aquifers (hardness of the rocks, depth of the water table, scattering of the clefts). The new drilling techniques (downhole hammer) solve some of these difficulties and many mediterranean countries prospect now such aquifers. They contain very fresh waters, even in arid areas. The deep tube wells are now cheap and easy to elaborate. Depending of geological structure, the hydrogeological behaviour will be different (with more or less permanent water stocks). Some Algerian examples show how the development plan must be adjusted to this structure.

Karst and Water Resources in the Hyper-Arid Areas of Northeastern Saudi Arabia, 1993, Edgell H. S.

Specificity of karst in arid and semi-arid areas. [in French], 1998, Salomon, Jeannol

Sources et hydrosystmes karstiques des rgions arides et semi-arides, essai gographique, 2000, Nicod, Jean
SPRINGS AND KARSTIC HYDROSYSTEMS IN THE ARID AND SEMI-ARID AREAS. A GEOGRAPHICAL ESSAY - The patterns of the main springs and hydrosystems in the deserts and surroundings are sorted, according to their geomorphological situation (piedmont, coastal or inner plateau), to structure of the aquifers and working of groundwater (storage capacity, artesian systems) and to the hydrochemical criteria particularly the solute load in Mg2+, SO42- and Cl-. From the best known examples, the main problems on the genesis and working of the karstic hydro-systems in arid environment are discussed: - the incidence of tectonic stress and paleokarstic and paleoclimatic inheritances; - the recent periods of recharge (in Northern Sahara and Near and Middle East); - the interactions in ionic solutions and hyper-karstic processes: particular_ly with the strong acid, H2SO4, the "double solvency effect", and the mixing water corrosion near the salt water wedge in the coastal karsts.

Aquifers: the ultimate groundwater-dependent ecosystems, 2006, Humphreys W. F. ,
Australian aquifers support diverse metazoan faunas comprising obligate groundwater inhabitants, largely crustaceans but also including insects, worms, gastropods, mites and fish. They typically comprise short-range endemics, often of relictual lineages and sometimes widely vicariant from their closest relatives. They have been confined to subterranean environments from a range of geological eras and may contain information on the deep history of aquifers. Obligate groundwater fauna ( stygobites) occurs in the void spaces in karst, alluvial and fractured rock aquifers. They have convergent morphologies ( reduction or loss of eyes, pigment, enhanced nonoptic senses, vermiform body form) and depend on energy imported from the surface except in special cases of in situ chemoautotrophic energy fixation. In Australia, many stygofaunas in arid areas occur in brackish to saline waters, although they contain taxa from lineages generally restricted to freshwater systems. They may occur alongside species belonging to taxa considered typical of the marine littoral although far removed in space and time from marine influence. The ecological attributes of stygofauna makes them vulnerable to changes in habitat, which, combined with their taxonomic affinities, makes them a significant issue to biodiversity conservation. The interaction of vegetation and groundwater ecosystems is discussed and, in places, there are conservation issues common to both

Microkarren in Australia - a request for information, 2007, Grimes, Ken G.
Microkarren are the smallest class of visible karren. They are finely-sculptured solutional forms, typically recognisable within a one centimetre grid. They come in a variety of patterns, of which fields of moderately to strongly sinuous microrills about 1mm wide and several decimetres long are the most conspicuous type. A descriptive terminology is suggested. Their genesis is uncertain, but appears to involve solution by thin films of water (dew, sea-spray or light rain) with surface-tension effects. In Australia their best development seems to be in the tropical monsoon (seasonally dry) and arid areas. However, these cryptic forms are poorly recorded and it is too early to make definite statements about their distribution. This note is a request for people to watch for them and report any sightings.

Microkarren in Australia - a request for information, 2007, Grimes K. G.

Microkarren are the smallest class of visible karren. They are finely-sculptured solutional forms, typically recognisable within a one centimetre grid. They come in a variety of patterns, of which fields of moderately to strongly sinuous microrills about 1mm wide and several decimetres long are the most conspicuous type. A descriptive terminology is suggested. Their genesis is uncertain, but appears to involve solution by thin films of water (dew, sea-spray or light rain) with surface-tension effects. In Australia their best development seems to be in the tropical monsoon (seasonally dry) and arid areas. However, these cryptic forms are poorly recorded and it is too early to make definite statements about their distribution. This note is a request for people to watch for them and report any sightings.


Middle-Late Quaternary paleoclimate of northern margins of the Saharan-Arabian Desert: reconstruction from speleothems of Negev Desert, Israel, 2010, Vaks Anton, Barmatthews Miryam, Matthews Alan, Ayalon Avner, Frumkin Amos

Speleothems in arid and hyper-arid areas of Negev Desert, Israel, are used in paleoclimate reconstruction of northern margins of Saharan-Arabian Desert, focused on the following objectives: 1) precise U–Th dating of the timing of speleothem growth as an indicator of periods of humid climate, i.e. positive effective precipitation; 2) the origin of rainfall using the speleothem δ18O and changes in spatial pattern of speleothem deposition and speleothem thickness along a north–south transect; 3) changes of vegetation cover based on speleothem δ13C variations.

During the last 350 ka major humid periods, referred to herein as Negev Humid Periods (NHP), occurred in the central and southern Negev Desert at 350–310 ka (NHP-4), 310–290 ka (NHP-3), 220–190 ka (NHP-2), and 142–109 ka (NHP-1). NHP-4, NHP-2 and NHP-1 are interglacial events, whereas NHP-3 is associated with a glacial period. During NHP-1, 2 and 3 the thickness and volume of the speleothems decrease from the north to the south, and in the most southern part of the region only a very thin flowstone layer formed during NHP-1, with no speleothem deposition occurring during NHP-2 and 3. These data imply that the Eastern Mediterranean Sea was the major source of the rainfall in northern and central Negev. More negative speleothem δ18O values, relative to central parts of Israel (Soreq Cave) are attributed to Rayleigh distillation because of the increasing distance from the Mediterranean Sea. Speleothem deposition during the NHP-4 in the southern Negev was more intensive than in most of the central Negev, suggesting the prominence of the tropical rain source.

Decrease in speleothem δ13C during NHP events indicates growth of the vegetation cover. Nevertheless, the ranges of δ13C values show that the vegetation remained semi-desert C4 type throughout the NHPs, with an additional significant carbon fraction coming from the host rock and the atmosphere. These observations, together with small thickness of the speleothem layers, favor that NHP events consisted of clusters of very short humid episodes interspersed with long droughts.

NHP events were contemporaneous with climate periods with monsoon index of ≥51 (cal/cm2 × day) and with the formation of sapropel layers in the Mediterranean Sea. Such simultaneous intensification of the monsoon and Atlantic-Mediterranean cyclones is probably related to the weakening of the high pressure cell above sub-tropical Atlantic Ocean, which enabled more rainfall to penetrate into the Saharan-Arabian Desert from the north and south. The contemporaneous occurrence of the NHP events and the increased monsoon rainfall could have opened migration corridors, creating climatic “windows of opportunity” for dispersals of hominids and animals out of the African continent.


Evolution of Intrastratal Karst and Caves in Gypsum, 2013, Klimchouk, A. B.

The term ‘intrastratal karst’ denotes a series of evolutionary karst types corresponding to successive stages of karst developmentin a soluble rock while it moves back to exposure after being buried by younger strata. The major boundaryconditions, the overall circulation pattern, and extrinsic factors and intrinsic mechanisms of karst development appear tochange considerably between the stages, resulting in characteristic styles of cave development and surface karst morphology,particularly distinct in case of gypsum karst.As gypsum is much more soluble than carbonates, it does not survive long in outcrops beyond arid areas. Wheregypsum is exposed to the surface with no substantial karstification formed during various stages of reburial, the developmentof epigene solution porosity in this rock is hindered due to the fast dissolution, being limited to flow paths in whichthe breakthrough conditions can be attained quickly. However, karst processes in gypsum develop extensively in intrastratalkarst settings, with inheritance from the deep-seated stage through the denuded one. Karstification may commence in anystage of intrastratal development, and during the next successive stage, the process, although in changed conditions, will beaffected significantly by the preformed solution porosity. Speleogenesis in deep-seated gypsum karst is exclusively hypogene.In subjacent karst, both hypogene and epigene speleogenesis may operate depending on the locally prevailing flowregime, but hypogene speleogenesis still dominates. In entrenched and denuded karst types, speleogenesis is overwhelminglyepigenic, but it is greatly facilitated by the presence of solution porosity inherited from the previous stages.Diverse and expressive karst landforms related to subsurface conduits evolve through different stages of the intrastratal karstdevelopment.The subsidence hazard in regions underlain by gypsum differs substantially between the karst types, so that one canobtain a kind of integrated general hazard assessment by classifying a given individual karst according to its evolution state.In general, various types of intrastratal karst, subjacent karst in particular, are the most potent in generating subsidence problems, whereas exposed karst types, particularly open karst, are the least prone to subsidence


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