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The book "Hypogene Karst Regions and Caves of the World" is finished
The book “Hypogene Karst Regions and Caves of the World” is going to be published by Springer, in its series “Cave and Karst Systems of the World”.
Karst session at the AGU Fall 2016 Meeting in San Francisco
There will be a karst session at the AGU Fall 2016 Meeting in San Francisco, USA in December 12-16: Characterization, Modeling, and Remediation of Fissured, Carbonate, and Karst Groundwater Systems
A new book on caves and karst in Austria
A book "Höhlen und Karst in Österreich" (Caves and karst in Austria; Editors: Christoph Spötl, Lukas Plan & Ehrad Christian) will be printed until mid of July. Subscription is available.
Unusual perspective on caves
Many inspiring ideas on caves can be found in images created by children, generated by the International Contest of Kid’s Drawing "Caves in the Eyes of our Children".
Session on Karst Aquifers at the 43th IAH Congress, France
A call to submit an abstract to a session devoted to karst aquifers, which will be held in September in Montpellier during the 43rd IAH Congress

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Did you know?

That basin method is a recharge method in which water is spread in shallow basins [16].?

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

Featured article from geoscience journal

Elseiver
Quaternary Science Reviews, 2010, Vol 29, Issue 19, p. 2647-2662
Middle-Late Quaternary paleoclimate of northern margins of the Saharan-Arabian Desert: reconstruction from speleothems of Negev Desert, Israel
Abstract:

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.