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 water conservation is all measures to reduce the quantitative of qualitative spoilage of water [16].?

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 subsidence depressions (Keyword) returned 1 results for the whole karstbase:
The occurrence of sinkholes and subsidence depressions in the far west Rand and Gauteng Province, South Africa, and their engineering implications, 2001, De Bruyn Ia, Bell Fg,
Dewatering associated with mining in the gold-bearing reefs of the Far West Rand, which underlie dolomite and unconsolidated deposits, led to the formation of sinkholes and subsidence depressions. Hence, certain areas became unsafe for occupation and were evacuated. Although sinkholes were initially noticed in the 1950s, the seriousness of the situation was highlighted in December 1962 when a sinkhole engulfed a three-story crusher plant at West Driefontein Mine. Consequently, it became a matter of urgency that the areas at risk of subsidence and the occurrence of sinkholes were delineated. Sink-holes formed concurrently with the lowering of the water table in areas which formerly had been relatively free of sinkholes. In addition, subsidence occurred as a consequence of consolidation taking place in the unconsolidated deposits as the water table was lowered. In the latter case, the degree of subsidence which occurred reflected the thickness and original density of the unconsolidated deposits which were consolidated. These deposits vary laterally in thickness and thereby gave rise to differential subsidence. Subsidence also occurred due to the closure of dewatered voids at the rock-soil interface. The risk of sinkhole and subsidence occurrence is increased by urban development, since interrupted natural surface drainage, increased runoff, and leakage from water-bearing utilities can result in the concentrated ingress of water into the ground. Where the surficial deposits are less permeable, the risk of instability is reduced. In the area underlain by dolomite, which extends around Johannesburg and Pretoria, these problem have been more notable in recent years because of housing development, both low-cost and up-market, and the growth of informal settlements. Residential densities may be very high, especially for low-cost housing, the development of which frequently has proceeded without recognition of the risk posed by karst-related ground instability. The appearance of significant numbers of small sinkholes has been associated with dolomite at shallow depth, that is, occurring at less than 15 m beneath the ground surface. The vulnerability of an area overlying dolomite bedrock at shallow depth is largely dependent on the spacing, width and continuity of grikes. When dolomite is located at depths greater than 15 m, the sinkholes which appear at the surface usually are larger in diameter. The risk of sinkhole occurrence in areas of shallow dolomite in general, may be greater, although the hazard itself is less severe. A classification system for the evaluation of dolomitic land based on the risk of formation of certain sized sinkholes has enabled such land to be zoned for appropriate development. Ongoing monitoring and maintenance of water bearing services, and the implementation of precautionary measures relating to drainage and infiltration of surface water are regarded as essential in developed areas underlain by dolomite. Special types of foundation construction for structures are frequently necessary

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