Community news

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 cupola is a hemispheric hill of limestone [10]. see also cone karst; cupola karst; mogote; pinnacle karst; tower karst. synonyms: (french.) cupole; (german.) halbkugel.?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms

What is Karstbase?

Search KARSTBASE:

keyword
author

Browse Speleogenesis Issues:

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;
See all featured articles from other geoscience journals

Search in KarstBase

Your search for arabia (Keyword) returned 39 results for the whole karstbase:
Showing 1 to 15 of 39
Paleoclimate and location of the border between Mediterranean climate region and the Saharo-Arabian Desert as revealed by speleothems from the northern Negev Desert, Israel, , Vaks A. , Barmatthews M. , Ayalon A. , Matthews A. , Frumkin A. , Dayan U. , Halicz L. , Mogilabin A. , Schilman B. ,
Speleothem bearing karstic caves of the northern Negev Desert, southern Israel, provides an ideal site for reconstructing the paleoclimate and paleo-location of the border between Mediterranean climate region and the Saharo-Arabian Desert. Major periods of speleothem deposition (representing humid periods) were determined by high resolution 230Th-U dating and corresponding studies of stable isotope composition were used to identify the source of rainfall during humid periods and the vegetation type. Major humid intervals occurred during glacials at 190-150[no-break space]ka, 76-25[no-break space]ka, 23-13[no-break space]ka and interglacials at 200-190[no-break space]ka, 137-123[no-break space]ka and 84-77[no-break space]ka. The dominant rainfall source was the Eastern Mediterranean Sea, with a possible small contribution from southern tropical sources during the interglacial periods. When the interglacial interval rainfall was of Eastern Mediterranean origin, the minimum annual rainfall was ~ 300-350[no-break space]mm; approximately twice than of the present-day. Lower minimum amounts of precipitation could have occurred during glacial periods, due to the cooler temperatures and reduced evaporation. Although during most of the humid periods the vegetation remained steppe with mixed C3 C4 vegetation, Mediterranean C3 type steppe-forest vegetation invaded southward for short periods, and the climate in the northern Negev became closer to Mediterranean type than at present. The climate was similar to present, or even more arid, during intervals when speleothem deposition did not occur: 150-144[no-break space]ka, 141-140[no-break space]ka, 117-96[no-break space]ka, 92-85[no-break space]ka, 25-23[no-break space]ka, and 13[no-break space]ka-present-day.Precipitation increase occurred in the northern Negev during the interglacial monsoonal intensity maxima at 198[no-break space]ka, 127[no-break space]ka, 83[no-break space]ka and glacial monsoonal maxima at 176[no-break space]ka, 151[no-break space]ka, 61[no-break space]ka and 33[no-break space]ka. However, during interglacial monsoonal maxima at 105[no-break space]ka and 11[no-break space]ka, the northern Negev was arid whereas during glacial monsoonal minima it was usually humid. This implies that there is not always synchroneity between monsoonal activity and humidity in the region.Oxygen isotopic values of the northern Negev speleothems are systematically lower than contemporaneous speleothems of central and northern Israel. This part is attributed to the increased rainout of the heavy isotopes by Rayleigh fractionation processes, possibly due to the farther distance from the Mediterranean coast

Flow of fossil groundwater, 1977, Bourdon Dj,
The great groundwater basins of North Africa and Arabia extend over an area of some 6.5 million square kilometres. Gradients on the isopiezometric surfaces of their confined ground-waters are generally interpreted as indicating present-day flow of groundwater. Can such flow occur in basins where most or all of the groundwater is fossil and where effective infiltration and recharge may have ceased some 10 000 years ago? Assuming that there is indeed no current recharge in these arid and sem-arid regions, the paper identifies seven groups totalling 12 possible mechanisms which can contribute in varying degrees to maintaining flow of groundwater long after effective recharge has ceased. These are: (i) Residual heads; (ii) Tilting of basin; (iii) Compaction effects, in terms of sediment loading, basalt loading and water loading/unloading; (iv) Thermal drive; (v) Gas drive; (vi) Lowering of discharge level, by tectonic displacement, by pressure bursts and by collapse of cover; and (vii) Evaporation in the discharge zone, such as lowering of lake levels and evaporation from sabkhas. Nine additional mechanisms were considered but rejected. Combinations of these mechanisms can produce heads inducing flow of fossil groundwater, but appear to be insufficient to account for present hydraulic regimes without some current surface recharge. The findings have direct application to studies leading to the development, use and management of these major water resources of the arid zones of the Sahara and Arabia

Geologic history of the Al Hasa area since the Pliocene, 1978, Hö, Tzl H. , Maurin V. , Zotl J. G.

Hydrogeology of the Umm Er Radhuma aquifer, Saudi Arabia, with reference to fossil gradients, 1982, Bakiewicz W, Milne Dm, Noori M,
Much of North Africa and the Arabian peninsula, lying in the Saharan climate zone, are underlain by huge tabular sandstone and carbonate aquifers, ranging in age from Cambrian to Tertiary. These are often saturated with water of reasonable quality and form very valuable resources in an area often desperately short of water. The Palaeocene Umm Er Radhuma carbonate aquifer is one such formation which has been the subject of intensive recent investigation. The formation contains groundwater of a reasonable quality, has adequate transmission and storage characteristics and hence considerable potential for future development. The origin of the water in such aquifers is the subject of continuing controversy. It is not disputed that the water is moving under the influence of regional groundwater gradients but origins of these gradients are the subject of considerable argument. On the one hand, there are those who hold that the presently observed gradients are fossil remnants of conditions created by a much wetter climatic regime prevalent some thousands of years ago. Against this are those who maintain that the gradients, at least in part, reflect a present day system with groundwater discharge in approximate dynamic equilibrium with recharge. This paper examines the hydrogeology of a typical Middle Eastern formation of the disputed kind, the Umm Er Radhuma aquifer in Saudi Arabia, and, with the aid of analytical and numerical models, attempts to resolve the problem of the origin of the observed groundwater gradients and to discover the extent to which the past must influence present day plans for future development

Karst Landforms in the Kingdom of Saudi Arabia, 1990, Peters Wm. David, Pint John J. , Kremla Norbert

Verkarstung und Grundwasser im As Summan Plateau (Saudi Arabien), 1993, Hoetzl H. , Wohnlich S. , Zoetl J. G. , Beninschke R.

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

HOLOCENE MARINE CEMENT COATINGS ON BEACH-ROCKS OF THE ABU-DHABI COASTLINE (UAE) - ANALOGS FOR CEMENT FABRICS IN ANCIENT LIMESTONES, 1994, Kendall C. G. S. , Sadd J. L. , Alsharhan A. ,
Marine carbonate cements, which are superficially like travertines from meteoric caves, are coating and binding some intertidal sedimentary rock surfaces occurring in coastal Abu Dhabi, the United Arab Emirates, (UAE). Near Jebel Dhana these surficial cements can be up to 3 cm thick and envelope beach rock surfaces and fossils. They are also present both as thin coats and a fracture-fill cement in the intertidal hard grounds associated with the Khor Al Bazam algal flats. The thickness, microscopic characteristics, and morphology of the marine cement coatings from Jebel Dhana indicates incremental deposition of aragonite in conjunction with traces of sulfate minerals. Most of these cement coatings are micritic, but the layers which encrust the hard grounds from the algae flat of the Khor al Bazam have a more radial and fibrous micro-structure and are composed solely of aragonite. The stable isotopic composition of coatings from Jebel Dhana (delta(18)O = .35, delta(13)C = .00) falls within the compositional range for modem marine non skeletal aragonite and suggests that the marine travertine-like cements precipitate from the agitated slightly hypersaline Arabian Gulf sea water during repeated cycles of exposure, evaporation and immersion. Similar cement coatings and microfabrics are present in the tepee structured and brecciated sediments of the Guadalupe Mountains (Permian) and the Italian Alps (Triassic), in Holocene algal head cements from the Great Salt Lace, and in similar Tertiary algal heads in the Green River Formation of the western US. The petrographic similarity of these ancient ''flow stone'' like cements with Recent hypersaline marine cement coatings suggests that high rates of carbonate cementation and hypersaline conditions contribute to tepee formation and cavity fill

Hydrogeological study and discharge features of the Niksar karst springs (Tokat-Turkey), 1997, Syed M. A. , Afsin M. , Celik M. ,
The exposed Paleozoic and Recent units in the study area have various hydrogeological characteristics such as pervious, semipervious, and impervious. Pervious limestones and associated impervious formations that were not influenced by tectonic movement are connected to produce karst springs. This paper presents the relationship between the discharge coefficient and other aquifer properties by using the hydrograph analyses of the karst springs. The magnitude of the discharge of the spring apparently controls the character of flow (such as laminar) and conduit in the aquifer. The correlation analysis shows a positive relation between Q(0)-Q(t), Q(0)-storage capacity, Q(t)-storage capacity, and alpha-discharge change, These results enhances the properties of the karst springs. Both monthly and annual rainfall contribute to spring discharge. All karst springwaters are suitable for household and food industry uses

Causes of land subsidence in the Kingdom of Saudi Arabia, 1997, Amin A, Bankher K,
The occurrence of land subsidence in the Kingdom Saudi Arabia is either natural or manmade. Natural land subsidence occurs due to the development of subterranean voids by a solution of host rocks in carbonate and evaporite terrains, over many areas of Saudi Arabia. Man-induced land subsidence is either due to the removal of groundwater in the agricultural areas or to wetting of unstable soils. Therefore, earth fissures and a lowering of the ground surface in unconsolidated sediments took place in alluvial plains and volcanic vent terrains. Unstable soils include Sabkha soils and loess sediments. These types of soils occur in coastal plains, desert areas and volcanic terrains. When this soil is wetted either during agricultural activities, waste disposal or even during a rain storm, subsidence takes place due to either the removal of salts from the Sabkha soil or the rearrangement of soil particles in loess sediments

Karst Hazard Assessment of Eastern Saudi Arabia, 1997, Amin Aa, Bankher Ka,

Speleothem-based paleoclimate record from northern Oman, 1998, Burns Sj, Matter A, Frank N, Mangini A,
U-Th age dating and stable isotope measurements of speleothems from Hoti Cave in northern Oman yield paleoclimate information from the region extending to 125 ka. The results (1) provide further confirmation of an early Holocene wet period in southern Arabia extending from some time prior to 9.7 ka and ending at 6.2 ka; (2) demonstrate a second period of wetness closely coinciding with the last interglacial period, marine isotope stage (MIS) 5e; (3) indicate that during MIS 5e, southern Arabia was considerably wetter than during the early Holocene; and (4) demonstrate that periods of increased monsoon wind strength, based on data from marine sediments, do not always coincide with evidence of greatly increased precipitation even from nearby continental areas

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.

Karstification and tectonic evolution of the Jabal Madar (Adam Foothills, Arabian platform) during the Upper Cretaceous, 2000, Montenat C. , Soudet H. J. , Barrier P. , Chereau A. ,
A palaeokarst system of Turonian age, located on the Arabian platform, at the front of the ophiolitic nappes of Oman (Jabal Madar, Adam foothills), is described and placed in its geodynamic context. The development of the karst network in a vadose context was favoured by an episode of fracturing (N-S to NW-SE fractures) that affected the Cenomanian platform carbonates of the Natih Formation. The karstic filling comprises two main types of speleothems: - laminated bioclastic calcarenites with graded bedding essentially deposited by gravity currents in a vadose regime; - crystallisation of large masses of white calcite in a saturated regime. The calcite was deposited during several episodes, and often constitutes most of the filling. The episode of uplift and emergence, accompanied by fracturing which favoured the development of the Madar karstic system, was probably induced by the swelling of the Arabian platform, in response to the initiation of the ophiolitic nappe obduction. Karstic filling probably occurred during the rise of marine level, what is suggested by mixing of vadose and marine influences (production of bioclastic calcarenites and later dolomitisation of these ones; crystallisation of white calcite of various origins as evidenced by cathodoluminescence data and carbonate isotopes). At the beginning of the Senonian, the Jabal Madar area was again submerged and incorporated in a relatively deep foreland basin where pelagic marls and turbidites were deposited (Muti Formation). The Jabal Madar (and its karstic system) and the whole of the Adam foothills were affected by folding towards the end of the Cretaceous, during the final phase of thrusting of the Omani nappes. The folding was strongly reactivated by post-obduction compressional movement which occurred during Miocene times

Middle Pleistocene Karst Evolution in the State of Qatar, Arabian Gulf, 2002, Sadiq, A. M. , Nasir, S. J.
Karst is widespread on the peninsula of Qatar in the Arabian Gulf, including depressions, sinkholes, caves, and solution hollows. More than 9700 large and small depressions, and several exposed sinkholes and caves are known. Field and air-photo studies indicate that the depressions, sinkholes, and caves of Qatar are genetically related, sinkholes representing an early phase in the development of depressions. Karst is concentrated mainly within the limestone, dolomite, gypsum, and anhydrite horizons of the Eocene Rus and Dammam Formations. Most karst features in Qatar show NE-SW and NW-SE orientations, similar to the joint and fracture systems. This observation indicates that rock type and the presence of joints and fractures played a major role in the development of karst in Qatar. Cylindrical, bottle-shaped, compound, and bowl-shaped morphotype karst pits were identified. These forms represent a genetic sequence in which the bowl-shaped pits evolved through a series of cylindrical and bottle-shaped compound intermediate stages. Most karst of central Qatar was formed due to extensive subsurface dissolution of carbonate and sulfate deposits under Middle Pleistocene wet climatic conditions and consequent subsidence. Joint-flow drainage may account for differential dissolution resulting in the formation of a pitted karst terrain in the northern part of Qatar.

Results 1 to 15 of 39
You probably didn't submit anything to search for