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Enviroscan Ukrainian Institute of Speleology and Karstology

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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. ...

Did you know?

That fissure is any discontinuity within the rock mass that is either initially open or capable of being opened by dissolution to provide a route for water movement. fissures in this sense, applied generally in karst, therefore include the primary sedimentary bedding planes as well as tectonic faults and joints. more specifically, the term has been used to describe voids with average dimensions from 10 to 100mm [9]. see also conduit; fracture.?

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

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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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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 transition (Keyword) returned 135 results for the whole karstbase:
Showing 1 to 15 of 135
Cave Animals and Their Environment, 1962,
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Richards, Aola M.

Caves can be divided into three distinct regions - the twilight zone, the transitional zone and the troglic zone. The main physical characters of caves - light, air currents, temperature and humidity - are discussed in relation to their effect on cave fauna. Various classifications of cave animals are mentioned, and those of Schiner and Jeannel discussed in detail. The paucity of food in caves, and its effect on the animal population is considered. Mention is made of the loss of secondary sexual characters and seasonal periodicity of breeding among true troglobites. Cave animals have undergone many adaptations to their environment, the most interesting of these being blindness and loss of pigment. Hyper-development of tactile, gustatory, olfactory and auditory organs and general slenderness of body, are correlated with eye degeneration. Several theories on the origin of cave fauna are discussed, and the importance of isolation on the development of cave fauna considered.

Processes of limestone cave development., 1964,
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Howard Alan D.
Three processes successively predominate in enlarging original fractures within limestone into cavern passages: (I) early dissolving by acid produced by oxidizing reactions within the groundwater as it flows through the limestone; (2) dissolving caused by the initial undersaturation with respect to calcite of the groundwater when it enters the limestone; and (3) increased dissolving which occurs at the transition from laminar to turbulent groundwater flow. Only those original fractures in limestone which are widest and which have a high hydraulic gradient acting across them will be enlarged into cavern passages. Until all available surface drainage has been diverted underground, cavern development takes place under a constant hydraulic head, and the rate of limestone solution increases with time. After all available surface drainage has been diverted underground, the discharge through the cave, rather than the hydraulic head, remains constant, and the rate of limestone solution decreases toward a constant value. These principles apply to caverns formed both by water-table flow and by artesian flow.

New data on the Foraminifera of the groundwaters of Middle Asia., 1976,
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Mikhalevich Valeria I.
New data obtained during the expedition to Middle Asia (1973) essentially enlarge our knowledge of foraminifera living in underground waters. Seven new species were discovered in the wells of the Kara-Kum and Ust-Urt deserts. All of them contain cytoplasma. The wells are situated in the region of bedding of underground waters of the heightened salinity in the zone of balance of runoff and evaporation. The majority of the species described in our work like many of the species recorded from the underground waters earlier (Brodsky, 1928; Nikoljuk, 1968; Jankovskaja and Mikhalevich, 1972) belong to the genera living in coastal brackish parts of tropical seas. This fact confirms the supposition of Brodsky about the transition of the marine coastal foraminiferal fauna to underground habitats after the regression of the sea. This fauna is a part of the underground fauna called by Nalivkin (1965) "the planetar fauna of the new type".

Spontaneous and induced acivity patterns in troglobite beetles (Genera Aphaenops, Geotrechus,Speonomus)., 1978,
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Lamprecht G. , Weber F.
In Constant temperature the troglobite beetles Aphaenops cerberus and pluto, Geotrechus orpheus and Speonomus diecki are aperiodically active. By periodogram analysis neither circadian nor ultradian or infradian periodic components can be found. Moreover there are no relevant correlations between the lengths of successive activity bursts and rest pauses. Consequently the activity patterns are stochasticly structured.; In cases with constancy of activity respectively rest behaviour the probabilities for the transition from activity to rest and from rest to activity are computed using the Frequency histograms of lengths of activity bursts and rest pauses. The transition probability is time-invariant if the observed histogram can be approximated to the negative exponential function. Y=ae -fx . The transition probability increases continuously if the observed histogram can be approximated to the Poisson or normal function. -74% of the investigated frequency histograms of the length of activity bursts and 57% of the histograms of the lengths of rest pauses can be approximated to one of the tested functions. -Aphaenops and Geotrechus specimens do not react to changes of the illumination intensity. Conversely temperature cycles induce distinct activity periodicities. In Aphaenops the mean length of activity bursts is -on the average; less temperature dependent than the mean length of rest pauses. Moreover, in this species the mean length of bursts is weakly negatively correlated with the mean length of pauses.; The evolution and adaptive reactions of the random mechanism of activity control in troglobite animals are discussed.

Palaeoenvironment of lateritic bauxites with vertical and lateral differentiation, 1983,
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Valeton Ida,
Formation of lateritic bauxites of the type described in this paper occurs world-wide in Cretaceous and Tertiary coastal plains. The bauxites form elongate belts, sometimes hundreds of kilometres long, parallel to Lower Tertiary shorelines in India and South America and their distribution is not related to a particular mineralogical composition of the parent rock. The lateral movement of the major elements Al, Si, Fe, Ti is dependent on a high level and flow of groundwater. Varying efficiency of subsurface drainage produces lateral facies variations. Interfingering of marine and continental facies indicate a sea-land transition zone where the type of sediments also varies with minor tectonic movements or sea-level changes. A typical sediment association is found in India, Africa, South and North America. It consists of (i) red beds rich in detrital and dissolved material of reworked laterites, (ii) lacustrine sediments and hypersaline precipitates, (iii) lignites intercalated with marine clays, layers of siderite, pyrite, marcasite and jarosite, and (iv) marine chemical sediments rich in oolitic iron ores or glauconite. A model is developed to account for element distributions in lateritic bauxites in terms of groundwater levels and flow. Finally it is shown that many high-level bauxites are formed in coastal plains and that they are subsequently uplifted to their present altitude

Subsidence and foundering of strata caused by the dissolution of Permian gypsum in the Ripon and Bedale areas, North Yorkshire, 1986,
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Cooper Ah,
Underground dissolution of thick gypsum beds in the Edlington Formation and Roxby Formation of the Zechstein sequence in North Yorkshire, England, has resulted in a 3 km-wide and 100 km-long belt of ground susceptible to foundering. Within this belt a large subsidence depression at Snape Mires, near Bedale, was largely filled with lacustrine deposits in the later part of the Late Devensian and during the Flandrian. South of Snape Mires the Nosterfield-Ripon-Bishop Monkton area has suffered about 40 episodes of subsidence in the past 150 years, and the presence of several hundred other subsidence hollows indicates considerable activity from the later part of the Devensian onwards. The linear and grid-like arrangement of these subsidence hollows indicates collapse at intersections in a joint-controlled cave system. Linear subsidence features at Snape Mires are also joint-controlled. The transition from anhydrite at depth to secondary gypsum near surface marks the down-dip limit of the subsidence-prone belt. Cavities are propagated upwards by roof collapse of caverns in the gypsum, leading to the formation of breccia pipes. Choking of the pipes can reduce the surface expression of the underground collapse, but the larger cavities are liable to produce pipes that reach the surface even at the eastern boundary of the 3 km-wide belt described. Further subsidence in the Ripon area is predicted and some suggestions for remedial measures are given

Observations prliminaires sur les cavits de la rgion du lac Centrum (NE Groenland), 1987,
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Loubiere, J. F.
CAVES OF CENTRUM LAKE AREA (NE GREELAND) - In 1983, M.Chiron, G.Favre, J-F. Loubire and J-P. Ttard identified a network of caves located in the extreme nord-east of Greenland. A cambro-silurian limestone zone stretches out to the south-west of Kronprins Christians land, the northern extremity of the great range of folded mountains of eastern Greenland. During an era characterised by the absence of permafrost and by a warmer climate favouring underground water circulation, these limestone formations were hollowed out by karstic river system. Such climatic conditions have long ceased to exist. During the major glaciations of the Quaternary period, the cavities were greatly modified. Glacier movements, cutting into the plateau, broke up the networks. The original underground deposits were then altered by allochtonous material of aeolian and morainic composition. Severe and ongoing frost shattering has added to this destructive process. It is hoped that this article will help to draw attention to these caves and to the more general subject of paleo-climates, especially their effects in the polar region during the Plio-Pleistocene transition (Electron Spin Resonance method on stalagmite and discovery of a mycelian hypha into calcite structure).

Genetic analysis of evolutionary processes, 1987,
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Wilkens Horst
Epigean and cave populations of A. fasciatus (Characidae, Pisces) differ in a series of morphological physiological, and ethological features. The interfertility of these populations made possible a genetic analysis of organs characteristic of interspecific divergence. The study of the regressive organs "eye" and "melanophore system" on the one hand and that of the constructively improved "gustatory equipment and feeding behaviour" on the other yielded identical principles of genetic manifestation: (1) All features have a polygenic basis with an at least di- to hexahybrid inheritance. (2) All polygenes have the same amount of expressivity. (3) After recombination of a minimum number of genes, discontinuous distributions (threshold effects) develop. (4) All features are independently inherited. (5) The genes responsible for a feature are unspecific. In the case of the eye this means that no "lens-" or "retinagenes" are analyzed; due to developmentally physiological interdependence within complex structures, only so-called "eye-genes" have as yet been described. Because of the developmentally physiological interdependence of complex organs, the process of reduction proceeds as a diminution in size, that of constructive evolution as enlargement. In both cases different allometric correlations of the single structures can be found. The convergent reduction of eyes in cave animals is caused by the loss of stabilizing selection which normally keeps the eye in its appropriate adapted form. It is not directional selection pressure, like f. ex. energy economy, but mutation pressure that causes eye reduction. By this, random mutations, which are mostly of deleterious character, are accumulated. The principles of regressive evolution are not restricted to the development of cave species. The absence of stabilizing selection regularly occurs during transitional evolutionary phases. These are f. ex. initial stages of speciation which may be observed when biotopes with little or no interspecific competition are colonized by an invader. Genotypic and phenotypic variability now arise and equilibria become punctuated, because stabilizing selection for a specific ecological niche which has once been acquired by the invading species is no longer acting. Examples include the evolution of species flocks in geologically young lakes or oceanic islands. Rapidly increasing variability now secondarily provides the material for directional selection which radiates such species into vacant niches. Genetic threshold effects as described above may accelerate this process. Variability will finally become lower again under the influence of inter- and intraspecific competition. A new equilibrium is attained.

Effect of climate changes on the precipitation patterns and isotopic composition of water in a climate transition zone: case of the eastern Mediterranean Sea area, 1987,
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Gat J. R. , Carmi I.

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Buigues D, Gachon A, Guille G,
From a geographical point of view, the atoll of Mururoa belongs to the Tuamotu archipelago. In its largest dimension Mururoa (28 x 10 km) is oriented N080-degrees-E, a direction which is different from that of the other atolls of the Tuamotu, generally oriented parallel to the Pacific plate motion, N130-degrees-E. The atoll of Mururoa is built on a submarine plateau of 130 km long and 30 km wide. The western side of this plateau is 90 km long and N080-degrees-E oriented, the eastern one 40 km long and N095-degrees-E oriented. Three deep main structures of the atoll are revealed by strong aeromagnetic anomalies elongated and oriented once more N080-degrees-E. They represent ancient riftzones, similar to the present time Hawaiian ones. The most important of them, situated at southern end of the atoll, is the prolongation of the eastern plateau. The principal petrographic facies have been defined from the numerous drill holes bored in the upper 1,100 m. From the base to the top are represented volcanic deposits, a volcano-sedimentary serie of both carbonate and volcanic origin and finally reefal carbonates (limestones and dolomites). The volcanic facies represent successively submarine, transitional and aerial volcanic activity. They are commonly affected by early stage of hydrothermalism, due to lava-sea-water chemical interaction, and are frequently supported by differentiated dykes, occasionally interrupted by reefal limestones. The main geometrical distribution of the facies through the atoll and the radiochronology lead to the following model of formation : during early stages of the atoll building two main separate edifices emerged before joining and forming a single volcano. This double structure was similar to the present time morphology of Tahiti. The volcanic activity ceased 10.6 Ma ago, an age which perfectly suits a hot spot origin, at present located to the south-east of Pitcairn island

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Boni M, Iannace A, Koppel V, Fruhgreen G, Hansmann W,
Several kinds of base metal deposits occur in the lower Paleozoic of southwest Sardinia (Iglesiente-Sulcis mineral district). This paper deals with those deposits which are generally referred to as Permo-Triassic, because they accompany and postdate the Hercynian orogeny and are related to magmatic activity. A large number of previously published geochemical data, integrated with additional new data (Sr, Pb, O, C, and S isotopes), are reviewed and discussed in the frame of the late to post-Hercynian geologic evolution of southwest Sardinia. According to geological and mineralogical characteristics, three types of deposits can be distinguished: (1) skarn ores related to late Hercynian leucogranitic intrusions, (2) high-temperature veins, and (3) low-temperature veins and karst filling. Pervasive epigenetic dolomitization phenomena are geochemically related to the low-temperature deposits. Sr and Pb isotopes of the first and second types (0.7097-0.7140 Sr-87/Sr-86; 17.97-18.29 Pb-206/Pb-204; 38.11-38.45 Pb-208/Pb-204) are distinctly more radiogenic than those of the third type (0.7094-0.7115 Sr-87/Sr-86; 17.86-18.05 Pb-206/Pb-204; 37.95-38.19 Pb-208/Pb-204) which, in turn, are closer to Paleozoic ores and carbonates. Fluid inclusion data indicate that the fluids responsible for mineralization of the first and second types of deposits were hot and dilute (T(h)= 370-degrees-140-degrees-C; <5 wt % NaCl equiv). In contrast, relatively colder and very saline fluids (T(h)= 140-degrees-70-degrees-C; >20 wt % NaCl equiv) were responsible for the third type of mineralization, as well for epigenetic dolomitization of the Cambrian host rocks. O isotopes measured in minerals from the first two types (deltaO-18SMOW = 12.8-18.9 parts per thousand) are O-18 depleted with respect to the third type (deltaO-18SMOW = 15.9-22.1 parts per thousand). These data, coupled with fluid inclusion formation temperatures, indicate that the fluids responsible for the first two types of mineralization were O-18 enriched with respect to those of the third type and related hydrothermal phenomena. The deltaS-34CDT in sulfides of the first two types vary between 3.7 and 10.73 per mil, whereas the values of the third type range from 12.0 to 17.9 per mil. Late to post-Hercynian mineralization is thus explained as the result of three distinct, though partly superimposed, hydrothermal systems. System 1 developed closer to the late Hercynian leucogranitic intrusions and led to the formation of the first and subsequently the second type of mineralization. The relatively hot and diluted fluids had a heated meteoric, or even partly magmatic, origin. Metals were leached from an external, radiogenic source, represented either by Hercynian leucogranites or by Paleozoic metasediments. Sulfur had a partly magmatic signature. System 2 was characterized by very saline, colder fluids which promoted dolomitization, silicification, and vein and karst mineralization. These fluids share the typical characteristics of formation waters, even though their origins remain highly speculative. The hydrothermal system was mainly rock dominated, with only a minor participation of the external radiogenic source of metals. Sulfur was derived by recirculation of pre-Hercynian strata-bound ores. System 3 records the invasion of fresh and cold meteoric waters which precipitated only minor ore and calcite gangue. It may represent the further evolution of system 2, possibly spanning a time well after the Permo-Triassic. The timing of all these phenomena is still questionable, due to the poor geologic record of the Permo-Triassic in southwest Sardinia. Nevertheless, the hypothesized scenario bears many similarities with hydrothermal processes documented throughout the Hercynian in Europe and spanning the same time interval. A comparison with the latter mineralization and hydrothermal activities leads to the hypothesis that the first two types of mineralization are linked to late Hercynian magmatic activity, whereas the third type may be related to either strike-slip or tensional tectonics which, throughout Europe mark the transition from the Hercynian orogeny to the Alpine cycle

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Dehon Ra,
Hrad Vallis is located in the transition zone between Elysium Mons and Utopia Planitia. Near its origin, at the northern edge of Elysium lavas, Hrad Vallis is characterized by a low-sinuousity channel within a north-northwest-trending, broad, flat-floored valley. A nearby flat-floored valley is parallel to the Hrad trend and parallel to elongate depressions, fissures, and faults in the region. An apparent hierarchy of landforms provides insight into the origin of the features associated with Hrad Vallis. The sequence leading to the development of Hrad Vallis consists of the following (1) formation of isolated depressions as either karst depressions or thermokarst valleys along faults and fissures in response to circulating ground water; (2) expansion of depressions along structural trends to coalesce as composite valleys, and (3) incision of a channel on the floor of Hrad valley by continued discharge of water from the subsurface after its initial formation by nonfluvial processes. Mud flows, polygonally fractured terrain, and chaotic terrain near the head of the major valleys suggest thixotropic behavior of saturated, clay-rich materials. An extended period of time is indicated during which freely circulating water existed on id beneath the surface of Mars. Karst and thermokarst processes imply very different climatic regimes and different host materials. The presence of karst topography implies extensive deposition of carbonates or other soluble rocks, whereas the presence of thermokarst basins implies the existence of porous, water/ice-saturated clastic or volcaniclastic materials

Le palokarst littoral de Provence (Estaque, Calanques et zone de Bandol), 1993,
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Blanc, J. J.
The general features of coastal paleokarst in Provence are describes: suspended gallery sections and drain-pipes cut across by fracturations or fault reactivation. The types of deformations and breaking observed are tilting, stalactite fall, extension fault sealing, reactivation and speleothem shearing, coastal wall and karstic cleft collapse as well as network deformation. The influence of structural environment is represented by overlapping strata, coastal faults and crossed-fault systems. Emphasis has been laid on the tectonic inheritance as well as the geodynamic context. To conclude, the importance of provenal-ligurian rifting mechanisms and the transition to faulted and distorted margin is underlined.

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Padilla A. , Pulidobosch A. , Mangin A. ,
Evaluation of recession hydrographs, from four karst springs in Europe, provides important information concerning the flow process operating in karst aquifer systems. Three analytic equations are used to evaluate the hydrographs: Mangin's equation, that assumes the recession is composed of both quickflow and baseflow; Coutagne's equation which considers the recession to be the response of a single reservoir; and a new function, H(t) (which is derived from Coutagne's equation), that refers to the whole recession curve. Using Mangin's equation it is apparent that the saturated zone and thus baseflow exerts nearly complete control over the discharge of La Villa spring and is fairly important at Fuente Mayor and Baget springs, but is much less significant at Aliou spring. The saturated zone accounts for 100%, 90%, 91%, and 40% respectively for these springs. Using Coutagne's equation and H(t) it is concluded that for Aliou and Baget springs, water flows freely in the high transmissive zones, but in the poorly transmissive zones, there is little continuity of connection in the system. At Fuente Mayor spring the differences in these zones are not so apparent and a gradual transition occurs. However, at La Villa spring, the karst aquifer is evidently much more homogeneous and the discharge is similar to that of a porous intergranular aquifer

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Evans Mw, Snyder Sw, Hine Ac,
We collected 43 km of high resolution seismic reflection profiles from a 14.5-hectare lake in the central Florida sinkhole district and data from three adjacent boreholes to determine the relationship between falling lake levels and the underlying karst stratigraphy. The lake is separated from karstified Paleogene to early Neogene carbonates by 65-80 m of siliciclastic sands and clays. The carbonate and clastic strata include three aquifer systems separated by clay-confining units: a surficial aquifer system (fine to medium quartz sand in the upper 20-30 m), the 25-35 m thick intermediate aquifer system (in Neogene siliciclastics), and the highly permeable upper Floridan aquifer system in Paleogene to early Neogene limestones. Hydraulic connection between these aquifer systems is indicated by superjacent karst structures throughout the section. Collapse zones of up to 1000 m in diameter and > 50 m depth extend downward from a prominent Middle Miocene unconformity into Oligocene and Upper Eocene limestones. Smaller sinkholes (30-100 m diameter, 10-25 m depth) are present in Middle to Late Neogene clays, sands, and carbonates and extend downward to or below the Middle Miocene unconformity. Filled and open shafts (30-40 m diameter; 10-25 m depth) ring the lake margin and overlie subsurface karst features. The large collapse zones are localized along a northeast-southwest line in the northern ponds and disrupt or deform Neogene to Quaternary strata and at least 50 m of the underlying Paleogene carbonate rocks. The timing and vertical distribution of karst structures are used to formulate a four-stage model that emphasizes stratigraphic and hydrogeologic co-evolution. (1) Fracture-selective shallow karst features formed on Paleogene/early Neogene carbonates. (2) Widespread karstification was limited by deposition of Middle Miocene clays, but vertical karst propagation continued and was focused because of the topographic effects of antecedent karst. (3) Groundwater heads, increase with the deposition of thick sequences of clastics over the semipermeable clays during Middle and Late Neogene time. The higher water table and groundwater heads allowed the accumulation of acidic, organic-rich soils and chemically aggressive waters that percolated down to Paleogene carbonates via localized karst features. (4) After sufficient subsurface dissolution, the Paleogene carbonates collapsed, causing disruption and deformation of overlying strata. The seismic profiles document an episodic, vertically progressive karst that allows localized vertical leakage through the clay-confining units. The spatial and temporal karst distribution is a result of deposition of sediments with different permeabilities during high sea levels and enhanced karst dissolution during low sea levels. Recent decreases in the potentiometric elevation of the Floridan Aquifer System simulates a sea-level lowstand, suggesting that karst dissolution will increase in frequency and magnitude

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