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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. ...

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. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
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 Silikatkarren is (german.) granites and related rocks that possess small outcrop sculpturing such as rounded runnels. they are best developed in the humid tropics such as malaysia [8].?

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KarstBase a bibliography database in karst and cave science.

Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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Geochemical and mineralogical fingerprints to distinguish the exploited ferruginous mineralisations of Grotta della Monaca (Calabria, Italy), Dimuccio, L.A.; Rodrigues, N.; Larocca, F.; Pratas, J.; Amado, A.M.; Batista de Carvalho, L.A.
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
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Your search for depression (Keyword) returned 206 results for the whole karstbase:
Showing 1 to 15 of 206
The Geology of the Cayman Islands (British West Indies), and their Relation to the Bartlett Trough, 1926, Matley Charles Alfred,
The Cayman Islands, a small dependency of the British Empire, with a local government controlled by the Government of Jamaica, occupy an isolated position of exceptional interest, both geographical and geological, in the Caribbean Sea. Situated between Jamaica and Cuba, and flanked on the south by the great depression of the Bartlett Trough, which descends over 20,000 feet within 18 miles of the shores of Grand Cayman, they are the only projecting peaks in the submarine ridge that extends from the Sierra Maestra of Cuba to the Misteriosa Bank in the direction of British Honduras. This ridge, though a recognized submarine feature, is irregular, and a depression of 7000 feet lies in it between Grand Cayman and the Lesser Caymans. The dependency consists of three islands, of which the two smaller, Cayman Brac and Little Cayman, are separated by only 4 miles of sea, while the third, Grand Cayman, is about 60 miles away. Cayman Brac is situated about 125 miles north-west of Montego Bay (Jamaica), and Grand Cayman lies 178 miles west-north-west of Negril Point, the nearest point of Jamaica, and about 150 miles from the Isle of Pines (Cuba). The combined area of the three islands is about 100 square miles. Columbus discovered the Lesser Caymans in 1503, and named them Las Tortugas', as the shores were swarming with turtle. Grand Cayman was discovered at some later unknown date, and is first recorded in history as being in the occupation of Spanish buccaneers. Europeans appear to have been ... This 250-word extract was created in the absence of an abstract

Further Caves of Kitava, Trobriand Islands, Papua, 1971, Ollier C. D. , Holdsworth D. K. , Heers G.

In a previous paper (Ollier and Holdsworth, 1970) we described the island of Kitava and many of the caves on the island. This note supplements that account and describes caves and related features discovered during a brief expedition to the south of the island (Figure 1) in 1971. Kitava is a coral island with a number of terraces and reaches a height of 466 feet. There is a central depression in the top of the island, the site of the lagoon before the reef was uplifted. Some caves are associated with the rim of the island, a few occur on mid-slopes, and others are found along the sea cliffs. Many of the caves have been used for burial of human remains, sometimes associated with pots, clam shells or canoe prows. Canoe prow burials are reported here for the first time. Some caves are associated with megalithic structures and legends of the origin of the various sub-clans (dala) of the island.


The cuticular surfaces of the gnathopods of two Amphipod Crustaceans: Niphargus (hypogean Gammarid) and Gammarus (epigean Gammarid)., 1972, Sellem Evelyne
Niphargus virei and N. schellenbergi (hypogean Gammarids) as also Gammarus pulex pulex (epigean Gammarid) show on the Gn1 and Gn2 of both sexes ornamented areas which were studied with a scanning electron microscope. The ornamentations are built up of teeth. These are simple in Gammarus pulex pulex and present a sexual dimorphism on the meropodite. In N. schellenbergi and N. virei they are as often as not grouped by three. In Orchestia (Talitrid) the teeth have their bases fusioned which forms pectinate scales showing a sexual dimorphism. Outside these areas, the gnathopod cuticle of N. virei, N. schellenbergi and Gammarus pulex pulex is ornamented with ovoid papilla, each of them surmounted by a finger-like process covering over a depression.

The cuticular surfaces of the gnathopods of two Amphipod Crustaceans: Niphargus (hypogean Gammarid) and Gammarus (epigean Gammarid)., 1972, Sellem Evelyne
Niphargus virei and N. schellenbergi (hypogean Gammarids) as also Gammarus pulex pulex (epigean Gammarid) show on the Gn1 and Gn2 of both sexes ornamented areas which were studied with a scanning electron microscope. The ornamentations are built up of teeth. These are simple in Gammarus pulex pulex and present a sexual dimorphism on the meropodite. In N. schellenbergi and N. virei they are as often as not grouped by three. In Orchestia (Talitrid) the teeth have their bases fusioned which forms pectinate scales showing a sexual dimorphism. Outside these areas, the gnathopod cuticle of N. virei, N. schellenbergi and Gammarus pulex pulex is ornamented with ovoid papilla, each of them surmounted by a finger-like process covering over a depression.

Morphometric analysis of surface depressions in the Mangapu karst. MSc thesis University of Auckland, New Zealand, 1973, Pringle J. M.

Karst processes of the eastern upper Galilee, Northern Israel, 1974, Gerson R,
Karst processes dominate most of the geomorphic activity in the Upper Galilee, consisting mainly of dolomites and limestones. Study of the chemical evolution of water passing through the karst hydrologic cycle clearly shows that the major portion of its carbonate solute is gained subaerially and in the upper part of the vadose zone. Most cave and spring water is already saturated with respect to aragonite and calcite.The karst depressions typical to surface morphology are mostly associated with fault-line traces. Their evolution is possible mainly in areas sloping initially less that 5[deg].The absence of evolved caves, representing well-developed karst of an earlier period, is attributed mainly to the marginal climate throughout the past combined with tectonic, and hence hydrologic, instability of the region.The discharge of the karst prings shows clearly dependence on annual precipitation, with a lag of about 2 years of the response to drought or more humid periods. Long-term fluctuations are larger in the smaller T'eo Spring than in the affluent 'Enan Springs.Most of the denuded material is extracted from the region as dissolved load via underground conduits and only small amounts as clastics. Mean long-term denudation is approximately 20 mm/1000 years, averaged for the surface area contributing to the springs.In spite of the above, most topographic forms are shaped by runoff erosion, active during medium to high intensity rainstorms. Solution processes prevail during low to medium rainfall intensities, while different parts of the region are denuded at similar rates. Even in karst depressions, erosion becomes dominant after their bottoms are covered by almost impervious terra-rossa mantle

Geomorphology of the North Karst, South Nahanni River Region, Northwest Territories, Canada, PhD Thesis, 1976, Brook, George Albert,

First investigated on the ground in June 1972, the Nahanni karst of northern Canada is the most complex karst terrain yet reported from high latitudes. It is centered at 61°28' N, longitude 124°05' W and lies within the zone of discontinuous permafrost. Mean annual temperature is 24°F and mean total precipitation 22.3 inches. Principal karst forms are fracture-located karst streets and irregularly-shaped closed depression called karst platea which may be up to 600 feet in depth. Platea often contain karst towers which are residuals of wall recession. Vertical-walled pond dolines up to 120 feet deep are common in bare karst areas while subjacent karst collapse, subsidence and suffosion depressions occur on marginal shale- and drift-mantled surfaces. Three small poljes have been identified, two produced entirely by solution, the other a structural form. These are periodically inundated. There are several peripheral fluvial canyons up to 3,000 feet deep that are blocked by glacial drift and which presently drain underground. Similarity in the hydrogeological properties of Nahanni Formation limestones at a variety of scales has led to the development of morphologically-identical karst forms which range in size from inches up to hundreds of feet. Furthermore, many of these landforms are part of a developmental sequence that at one scale links vertical-walled dolines, karst streets, platea and poljes; and at another links solution pits, grikes and joint hollows on limestone pavements. The evidence suggests that poljes form by the coalescence of dolines and uvalas just as Cvijic suggested in 1918. In attempting to explain the almost "tropical" nature of the sub-arctic Nahanni karst landform assemblage, a number of facts are of importance.
(a) The Nahanni Formation limestones have been highly warped and intensively fractures during the past one million years. Open fractures have encouraged karstification by allowing easy movement of water underground. Warping has provided the relief necessary for the development of solutional forms with a distinct vertical component.
(b) The karst can not be considered relict because it was glaciated during the Pleistocene. In addition the hydrological activity in it today is comparable with that in many humid tropical karst areas.
(c) Solutional denudation rates governed by aspects of surficial and bedrock geology may in some localized areas be equivalent to rates in humid tropical carbonate regions.
(d) At present rates, the most highly developed forms could have been produced within the last 200,000 years and because there is evidence to indicate that the karst may not have been glaciated for up to 250,000 years, such a period has been available for solutional development.
Because the Nahanni region has not been glaciated for an extremely long period, it may be one of only a few high-latitude carbonate terrains that have had time to develop fully. Its very existence questions the validity of the concept that the intensity and direction of karst development is climate-controlled. In the Nahanni at least, the structural and lithological properties of the host limestone appear to have been of greater importance. The labyrinth karst type present in regions of humid-tropical to sub-arctic climate, is an outstanding example of a structurally-controlled karst landscape. It may well be that the same controls also influence the distributions of other karst types.


Diffuse flow and conduit flow in limestone terrain in the Mendip Hills, Somerset (Great Britain), 1977, Atkinson T. C.
The hydrogeology of the karstic Carboniferous Limestone is described. Water tracing has established recharge areas for fifteen major springs and water budgets confirm the size of the areas found. Groundwater flow occurs in two modes: turbulent conduit flow and diffuse Darcian flow in fine fractures. Recharge is 50% quickflow via caves and closed depressions and 50% slower percolation. Active storage in the diffuse component (S = 0.92%) is 30 times greater than in phreatic conduits. Diffuse hydraulic conductivity is 0.89 m day−1 and an average of 60?80% of groundwater is transmitted by conduits in this maturely karsted and steeply dipping aquifer.

Karst depressions in a time context., 1978, Kemmerly P. R. , Towe S. K.

Karst development in Ordovician carbonates: Western Platform of Newfoundland, Master of Science (MS) Thesis, 1978, Karolyi, Marika Sarolta

The Appalachian fold belt system in Newfoundland is divided into three tectonic divisions: Western Platform; Central Mobile Belt; Avalon Platform Rocks of the Western Platform range in age from Precambrian to Carboniferous. Major karst areas are found there is Ordovician and Carboniferous rocks. Karst features of the study area (Goose Arm to Bonne Bay Big Pond) are in the Ordovician carbonates of the undivided St. George and Table Head Formations, covering a few hundred square kilometers. Features include karren, sinkholes, sinking streams, and karst springs, caves and other solutional and collapse features.
In the study area multiple fold and faulting episodes complicate the geology. Extensive and probably repeated glaciations have produced rugged terrane with U-shaped valleys and as much as 300m relief on the carbonates. There is variable but thick till cover. A class or classes of ice-scoured closed depressions with internal drainage are recognized. Postglacial karst forms are limited to varieties of karren (mainly littoral), small sinkholes, and cave systems that are inaccessively small in most instances. Distribution of all karst features is highly irregular.
Hydrologic patterns follow fluvial, fluviokarstic and holokarstic drainage. Large number of sinking ponds have seasonal overflow channels. The ground water drainage routes are generally short and shallow, with varied hydraulic gradients. Few instances of ground water route integration to regional springs is found.
The water chemistry of the area displays a tight normal distribution of hardness. This is attributed to the ponding effect. Seasonal trends show an overall increase in total hardness and other parameters, with some ponds showing linear increases and others cyclic variations.
Karst type and distribution is complex and irregular, but both glaciokarstic and karstiglacial development is present. The majority of karst forms point to karstiglacial development where previous karst forms have been modified by ice. Karstification is controlled by geology, rock lithology, hydraulic gradients and glacial scour and infill. Karstic processes continue to operate today, modifying the scoured basins and creating new karst forms.


Surface Lowering and Landform Evolution on Aldabra, 1979, Trudgill S. T. ,
Aldabra landforms are the result of the karstification of carbonate rocks distributed on surfaces which have been exposed to erosion for varying lengths of time. Morphometric analysis (which is of interest in both geomorphological and botanical contexts) suggests that the most well developed karst features (closed depressions) occur on what appear to be the oldest surfaces. Morphology also varies with lithology. Measurements of present-day erosion rates suggests that weakly cemented rocks and the most soluble mineral components are eroding most rapidly. The evolution of a dissected morphology is related to lithological heterogeneity in coralline rocks or, in the case of the more homogeneous rocks, to the short residence time of waters on the rock surface (the more rapidly dissolving mineral grains eroding faster). Dissolution also proceeds in fresh water pools, but this may be offset by precipitation in some cases. The surface is mostly case hardened, except under deep organic soils where erosion rates are much higher than in other areas. A mean erosion rate measured at 0.26 mm/a appears to make it feasible that large erosional features, such as the lagoon, could have been formed during periods of emersion as suggested by research workers who have hypothesized that an atoll shape may be substantially derived by subaerial weathering

Hydrological processes in karst depressions., 1981, Gunn J.

Spatial analysis of a karst depression population: clues to genesis., 1982, Kemmerly P. R.

Spatial analysis of a karst depression population; clues to genesis, 1982, Kemmerly Phillip R. ,

Cavern Development in the Dimensions of Length and Breadth. PhD Thesis, 1982, Ewers, Ralph Owen

Three conceptual models are proposed for the integration of the large systems of conduits responsible for groundwater flow in soluble rocks. These models are supported by laboratory experiments with scaled solution models, flow-field analogues, and evidence from existing caves.
The three models reflect different boundary conditions imposed by geologic structure and stratigraphy. They have three characteristics in common. First, the smaller elements of the larger systems propagate separately from points of groundwater input toward points of discharge as distributary networks. Second, the integration of the smaller networks proceeds headward from the resurgence, in a stepwise fashion. Third, the result of the integration process in each case is a tributary system with many inputs discharging through a single discharge point.
The potential for growth of each of the smaller networks, within a common pressure field, is related to its distance from the discharge boundary and the distribution of other inputs. The first input to establish a low-resistance link to the discharge boundary will effect a localized depression within the potential field, thus attracting the flow and redirecting the growth of nearby networks until they eventually link with it. As additional orders of links develop, the system takes on a tributary pattern.
The first model applies to steeply dipping rocks. Inputs occur where bedding planes are truncated by erosion, and discharge takes place to the strike. Conduits in this case evolve as a roughly rectangular grid of strike and dip oriented elements. Dip elements are the initial form, with subsequent integration along the strike. The type example is the Holloch in Switzerland.
The second model applies to flat-lying rocks. Inputs occur over a broad area, and discharge takes place along a linear boundary. Conduits in this case evolve in a trellised array with elements normal to the discharge boundary predating those parallel to it. These latter conduits integrate the flow. The type example is the Mammoth Cave Region, Kentucky.
The third model applies to simple systems which occur beneath an impermeable cap rock. Inputs occur where erosion has breached the capping beds. The type example is Cave Creek, Kentucky.


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