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Enviroscan Ukrainian Institute of Speleology and Karstology


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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 oxygen demand is the ability of substances to utilize dissolved oxygen in water.?

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.
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

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Your search for salt (Keyword) returned 249 results for the whole karstbase:
Showing 226 to 240 of 249
Hydrogeology of gypsum Formations in Iran, 2013,
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Raeisi E. , Zare M. , Aghdam J. A.

The gypsum formations in Iran are mainly Upper Red (URF), Gachsaran (GF), and Sachun. The GF is divided into salt (SGF) and its non-salt equivalents (NSGF). The conductivity of the spring’s water in Sachun, URF and NSGF is below 3500 mS cm21, but the conductivity of the SGF varies from 2400 to 400,000 mS cm21. Three different sites, Tangsorkh (NSGF), Ambal and Salbiz (SGF), were selected for further studies. The Tangsorkh area is composed of alternating units of marlstone and gypsum. The hydraulic connections between these units are broken by the marls and no sub-aquifer is developed in the gypsum units due to their small catchment area and lack of karst development. The Ambal area, adjacent to the large Karun River, consists of units of marl, anhydrite, and halite. Sinkholes cover all parts of the area. Contact of Karun River with the Amble ridge causes the chemistry of the river to evolve from bicarbonate type to chloride type. The presence of the Karun River inside this ridge formed a network of karstic conduits and sinkholes, which causes the marly layers to collapse such that the Ambal area cannot be considered to have several independent subaquifers. The Salbiz site is composed of alternating units of marl-marlstone and gypsum without any sinkholes or exposed salt layers. It consists of independent sub-aquifers with general flow directions parallel to the strike. The study indicates that the GF is mainly composed of small independent sub-aquifers due to its alternative marl or marlstone layers, resulting water flows parallel to the strike, except in the SGF under specific conditions.


Comparison of discharge, chloride, temperature, uranine, dD, and suspended sediment responses from a multiple tracer test in karst, 2013,
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Luhmann A. J. , Covington M. D. , Alexander S. C. , Chai S. Y. , Schwartz B. F. , Groten J. T. , Alexander Jr. E. C.

A controlled recharge event with multiple tracers was conducted on August 30, 2010. A pool adjacent to a sinkhole was filled with approximately 13,000 L of water. The water was heated, and salt, deuterium oxide, and uranine were added. The pool was then emptied into the sinkhole, and data were collected at Freiheit Spring approximately 95 m north of the sinkhole to monitor changes in discharge, temperature, conductivity/chloride, dD, uranine, and suspended sediment. This combined trace demonstrated the feasibility and utility of conducting superimposed physical, chemical, and isotopic traces. Flow peaked first at the spring and was followed by a suspended sediment peak; then essentially identical uranine, chloride, and dD peaks; and finally a temperature peak. The initial increase in flow at the spring recorded the time at which the water reached a submerged conduit, sending a pressure pulse to the spring at the speed of sound. The initial increase in uranine, chloride, and dD at the spring recorded the arrival of the recharge water. The initial change in temperature and its peak occurred later than the same parameters in the uranine, chloride, and dD breakthrough curves. As water flowed along this flow path, water temperature interacted with the aquifer, producing a delayed, damped thermal peak at the spring. The combination of conservative and nonconservative tracers illustrates unique pressure, advective, and interactive processes.


Marine seismic-reflection data from the southeastern Florida Platform: a case for hypogenic karst, 2013,
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Cunningham, Kevin J.

Recent acquisition of twenty marine seismic-reflection profiles suggests a hypogenic karst origin for the Key Biscayne sinkhole located on the seafloor of Miami Terrace at the southeastern part of Florida Platform. Analysis of the seismic-reflection data strongly suggest the submarine sinkhole was produced by dissolution and collapse of Plio(?)-Pleistocene age carbonate strata. A complex fault system that includes compres-sional reverse faults underlies the sinkhole, providing a physical system for the possible exchange of groundwater with the sinkhole. One seismic profile is suggestive of a mas-ter feeder pipe beneath the sinkhole. The feeder pipe is characterized by seismic-reflection configurations that resemble megabreccia and stratal collapse. The sinkhole is located at a depth of about 365 m below sea level. The record of sea-level change dur-ing the Plio(?)-Pleistocene and amount of subsidence of the Florida Platform during this span of time indicates that the sinkhole has always been submerged at a water depth of about 235 m or more. Thus, the near-surface epigenic karst paradigm can be ruled out. Possible hypogenic models for sinkhole formation include ascending fluids along the fault system, such as, dissolution related to the freshwater/saltwater mixing at a regional groundwater discharge site, or processes related to gases derived from gener-ation of hydrocarbons within deep Mesozoic strata. Hydrocarbon-related karstification provides several possible scenarios: (1) oxidation of deep oil-field derived hydrogen sulfide at or near the seafloor to form sulfuric acid, (2) reduction of Cretaceous or Paleocene anhydrite or both by oil-field methane to form hydrogen sulfide and later oxidation to form sulfuric acid, and (3) carbon-dioxide charged groundwater reacting to form carbonic acid. Further, anerobic microbes could form methane outside of a hy-drocarbon reservoir that ascends through anhydrite to form hydrogen sulfide and later oxidized to sulfuric acid.


Karst hierarchical flow systems in the Western Cordillera of North America, 2013,
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Ford, Derek

By definition, karstic flow systems are networks of solutional conduits. Their spatial patterns and hierarchical organisation are strongly affected by differing lithology and geologic structure, and by the location and modes of recharge – unconfined, confined, interformational. For purposes of discussion, this paper will review six examples rang-ing across platform and reefal limestones and dolostones, dolostone breccias, gypsum and salt, in widely differing structural, geomorphic and hydrologic settings: (1) The Carcajou River karst at Lat. 65° N in the Mackenzie Mountains, where leaky permafrost superimposes a frozen ground hierarchy on those due to lithology, structure and topog-raphy: (2) The S Nahanni River karst at Lat. 62° N, with an intrusive-derived local thermal system and lengthy, strike-oriented meteoric flow systems that contribute to an outlet H2S thermal system at the basin topographic low: (3) Castleguard Mountain Karst (Lat. 52° N) in massive Main Ranges structures of the Rocky Mountains, with a complex alpine hierarchy of base-flow and overflow springs: (4) Crowsnest Pass, in steep thrust structures in the Rocky Mountain Front Ranges, where regional strike-oriented flow systems extending between Lats. 49° and 50° N and paired above and below a major aquitard have been disaggregated by glacial cirque incision: (5) The Black Hills geologic dome at Lat. 44° N in South Dakota, USA, with a sequence of hot springs at low points around the perimeter, discharging through sandstones but with some of the world’s most extensive hypogene maze caves formed in a limestone karst barré setting behind them: (6) The Sierra de El Abra, at Lat. 23° N in Mexico, a deep and lengthy (100 km) reef-backreef limestone range being progressively exposed and karstified by stripping of a cover of clastic rocks; the springs are few but amongst the largest known in karst anywhere, located at the northern and southern low extremities along the strike of the reef, plus breaches (windows) in the cover further south.


The Grosmont: the worlds largest unconventional oil reservoir hosted in polyphase-polygenetic karst, 2013,
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Machel Hans G. , Borrero Mary Luz, Dembicki Eugene, Huebscher Harald4

The Upper Devonian Grosmont platform in Alberta, Canada, is the world’s largest heavy oil reservoir hosted in carbonates, with 400-500 billion barrels of IOIP at an average depth of about 250 – 400 m. Advanced thermal recovery technologies, such as SAGD and electrical in-situ retorting, much higher world market prices for oil and certain political pressures have led to a flurry of activity in the Grosmont since 2006.
The sedimentary stratigraphy of the Grosmont reservoir consists of six stacked car-bonate units interbedded with marls and some evaporites. The latter two originally acted as aquitards during diagenesis but are breached or missing in parts of the area today. Dolomitization by density-driven reflux was the first pervasive diagenetic pro-cess. A dense fracture network was created in three or four phases. Most fractures probably originated from collapse following subsurface salt dissolution and/or from Laramide tectonics far to the west, whereby pulsed crustal loading in the fold-and-thrust belt created a dynamic forebulge in the Grosmont region via multiple pulses of basin-wide crustal flexing, each followed by relaxation. The fracture network probably was reactivated and/or expanded by glacial loading and post-glacial isostatic rebound in the Pleistocene and Holocene, respectively.
The region experienced three or four prolonged periods of epigene karstification, alt-hough there is tangible evidence for only two of them in the Grosmont platform. The first of these episodes was a ‘warm epigene karstification’ during the Jurassic - Creta-ceous, and the second was/is a ‘cold epigene karstification’ that started sometime in the Cenozoic and is continuing to this day. In addition, there is circumstantial evidence for hypogene ‘karstification’ (= dissolution) throughout much of the geologic history of the Grosmont since the Late Devonian. Karstification was accompanied and/or by fol-lowed by extensive hydrocarbon biodegradation.


Morphology and geology of an interior layered deposit in the western Tithonium Chasma, Mars, 2013,
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Baioni, Davide

This paper describes a morphologic and morphometric survey of a 3.1 km-high, domeshaped upland in western Tithonium Chasma (TC) which coincides with areas containing abundant surface signatures of the sulphate mineral kiersite, as identified by the OMEGA image spectrometer. The morphologic features of the dome were investigated through an integrated analysis of the available Mars Reconnaissance Orbiter High Resolution Imaging Science Experiment (HiRISE), Mars Orbiter Camera, and Context Camera data, while the morphometric characteristics of the structure were measured using a topographic map (25-m contour interval) built from high-resolution stereo camera (HRSC) and Mars Orbiter Laser Altimeter (MOLA) data.
The dome displays surface features that were apparently formed by liquid water probably released from melting ice. These features include karst landforms as well as erosive and depositional landforms. The surface of the dome has few impact craters, which suggests a relatively young age for the dome. Layers in the dome appear laterally continuous and are visibly dipping toward the slopes in some places.
The mineralogical and structural characteristics of the dome suggest that it was emplaced as a diapir, similar to the dome structure located in the eastern part of TC, and to many salt diapirs on Earth.


Morphology and geology of an interior layered deposit in the western Tithonium Chasma, Mars, 2013,
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Baioni, Davide

This paper describes a morphologic and morphometric survey of a 3.1 km-high, domeshaped upland in western Tithonium Chasma (TC) which coincides with areas containing abundant surface signatures of the sulphate mineral kiersite, as identified by the OMEGA image spectrometer. The morphologic features of the dome were investigated through an integrated analysis of the available Mars Reconnaissance Orbiter High Resolution Imaging Science Experiment (HiRISE), Mars Orbiter Camera, and Context Camera data, while the morphometric characteristics of the structure were measured using a topographic map (25-m contour interval) built from high-resolution stereo camera (HRSC) and Mars Orbiter Laser Altimeter (MOLA) data.

The dome displays surface features that were apparently formed by liquid water probably released from melting ice. These features include karst landforms as well as erosive and depositional landforms. The surface of the dome has few impact craters, which suggests a relatively young age for the dome. Layers in the dome appear laterally continuous and are visibly dipping toward the slopes in some places.

The mineralogical and structural characteristics of the dome suggest that it was emplaced as a diapir, similar to the dome structure located in the eastern part of TC, and to many salt diapirs on Earth.


PROBLEMS OF VALORIZATION AND MANAGEMENT OF THE GIANT GEODE OF PULPI (ALMERIA, SE SPAIN) , 2013,
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Calaforra, Josemaria

The Giant geode of Pulpí (Almería, SE Spain) hosts some of the most outstanding selenite crystals of the world and the largest ones discovered in Europe. Pinacoidal high-purity selenite crystals up to 2 metres long cover totally its walls, floor and ceiling. The cave void where the geode was formed is in an abandoned mine 3 km far from the coastline and 50 m deep from the surface. The peculiar genesis could be related to the mixing processes between hydrothermal fluids and salt water in the aquifer. The discovery (December 2000) was considered an important highlight in the geological heritage of Spain but not many things have been done since 10 years. Projects developed for their conservation were paralysed and no legal figure of protection is active nowadays. Only the interest of touristic valorisation is still alive but in reality the initial tourist projects are stopped. Only one previous project of “waste mining removal” is active. Nevertheless this project is partially provoking a controversial effect: the destruction and/or decontextualization of some surface mining remains. No doubt the Geode has a tourist interest, which must be tempered by environmental restrictions limiting the public visits. First results demonstrated that a continuous visit of two or three people for more than 10 min- utes provokes the appearance of condensation and risks of corrosion of the gypsum crystals. Although any tourist adaptation must not permit direct visits to the geode indoor and levels/contents like Hg and Rn must be controlled. Regrettably, communication to the authorities of this special situation decreased their interest for the protection and touristization. The present proposal is to highlight not only the geode but the mining environment showing that valorization of this geological-natural heritage is still feasible.


Deep 3D thermal modelling for the city of Berlin (Germany), 2013,
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Sippel Judith, Fuchs Sven, Cacace Mauro, Braatz Anna, Kastner Oliver, Huenges Ernst, Scheckwenderoth Magdalena

This study predicts the subsurface temperature distribution of Germany’s capital Berlin. For this purpose, a data-based lithosphere-scale 3D structural model is developed incorporating 21 individual geological units. This model shows a horizontal grid resolution of (500 9 500) m and provides the geometric base for two different approaches of 3D thermal simulations: (1) calculations of the steadystate purely conductive thermal field and (2) simulations of coupled fluid flow and heat transport. The results point out fundamentally different structural and thermal configurations for potential geothermal target units. The top of the Triassic Middle Buntsandstein strongly varies in depth (159–2,470 m below sea level) and predicted temperatures (15–95 _C), mostly because of the complex geometry of the underlying Permian Zechstein salt. The top of the sub-salt Sedimentary Rotliegend is rather flat (2,890–3,785 m below sea level) and reveals temperatures of 85–139 _C. The predicted 70 _C-isotherm is located at depths of about 1,500–2,200 m, cutting the Middle Buntsandstein over large parts of Berlin. The 110 _C-isotherm at 2,900–3,700 m depth widely crosscuts the Sedimentary Rotliegend. Groundwater flow results in subsurface cooling the extent of which is strongly controlled by the geometry and the distribution of the Tertiary Rupelian Clay. The cooling effect is strongest where this clay-rich aquitard is thinnest or missing, thus facilitating deep-reaching forced convective flow. The differences between the purely conductive and coupled models highlight the need for investigations of the complex interrelation of flow- and thermal fields to properly predict temperatures in sedimentary systems.


The mineral springs of the Scrajo spa (Sorrento peninsula, Italy): a case of natural seawater intrusion, 2013,
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Corniello A. , Trifuoggi M. , Ruggieri G.

This paper deals with the mineral springs feeding the Scrajo spa in the Sorrento peninsula southeast of Naples, approximately 6 km from Castellammare di Stabia, another spa location. The Scrajo mineral water is sulphureous, salt-bromine-iodic and CO2-rich. The two hydromineral areas fall within the groundwater basin of Mt. Faito formed chiefly by limestones. Due to the high permeability of the limestones, there is considerable rainwater infiltration which recharges a basal fresh groundwater resting on denser seawater. This groundwater body feeds the mineral springs of the Scrajo spa, the springs of Castellammare di Stabia and some submarine springs. All the data gathered for the Scrajo springs led to propose the following mineralisation scheme: (1) The basal fresh groundwater of Mt. Faito (on underlying seawater) receives endogenous contributions of CO2 and H2S which cause a ‘‘natural’’ seawater intrusion within the fresh groundwater; (2) The upwelling of gases would appear to occur via the major faults which bound Sorrento peninsula to the NW; (3) During the year, the chemistry of the springs changes according to different degrees of seawater intrusion: the minimum occurs in June and the maximum in November. The close interaction between the sea and the Scrajo’s mineral waters (but also those of Castellammare di Stabia) highlights their particular vulnerability not only to overextraction of groundwater but also to climate change. Finally, a hypothesis is presented to explain the connection between the mineral waters rich in CO2 and H2S and the concentration of karst phenomena observed in the Scrajo area.


Deep 3D thermal modelling for the city of Berlin (Germany), 2013,
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Sippel Judith, Fuchs Sven, Cacace Mauro, Braatz Anna, Kastner Oliver, Huenges Ernst, Scheckwenderoth Magdalena

This study predicts the subsurface temperature distribution of Germany’s capital Berlin. For this purpose, a data-based lithosphere-scale 3D structural model is developed incorporating 21 individual geological units. This model shows a horizontal grid resolution of (500 9 500) m and provides the geometric base for two different approaches of 3D thermal simulations: (1) calculations of the steady state purely conductive thermal field and (2) simulations of coupled fluid flow and heat transport. The results point out fundamentally different structural and thermal configurations for potential geothermal target units. The top of the Triassic Middle Buntsandstein strongly varies in depth (159–2,470 m below sea level) and predicted temperatures (15–95 _C), mostly because of the complex geometry of the underlying Permian Zechstein salt. The top of the sub-salt Sedimentary Rotliegend is rather flat (2,890–3,785 m below sea level) and reveals temperatures of 85–139 _C. The predicted 70 _C-isotherm is located at depths of about 1,500–2,200 m, cutting the Middle Buntsandstein over large parts of Berlin. The 110 _C-isotherm at 2,900–3,700 m depth widely crosscuts the Sedimentary Rotliegend. Groundwater flow results in subsurface cooling the extent of which is strongly controlled by the geometry and the distribution of the Tertiary Rupelian Clay. The cooling effect is strongest where this clay-rich aquitard is thinnest or missing, thus facilitating deep-reaching forced convective flow. The differences between the purely conductive and coupled models highlight the need for investigations of the complex interrelation of flow- and thermal fields to properly predict temperatures in sedimentary systems.


KARST HAZARDS, 2013,
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Andreychouk Viacheslav, Tyc Andrzej

Karst hazards are an important example of natural hazards. They occur in areas with soluble rocks (carbonates, mostly limestone, dolomite, and chalk; sulfates, mostly gypsum and anhydrite; chlorides, mostly rock salt and potassium salt; and some silicates, quartzite and amorphous siliceous sediments) and efficient underground drainage. Karst is one of the environments in the world most vulnerable to natural and human-induced hazards. Karst hazards involve fast-acting processes, both on the surface and underground (e.g., collapse, subsidence, slope movements, and floods) and their effects (e.g., sinkholes, degraded aquifers, and land surface). They frequently cause serious damage in karst areas around the world, particularly in areas of intense human activity. Karst threat is the potential hazard to the life, health, or welfare of people and infrastructure, arising from the particular geological structure and function of karst terrains. The presence of underground cavities in the karst massif masks the threat from the hazards of collapse. This means that in some instances, the potential threats from karst, which are inherent features of the karst environment, become hazards. They range in category from potential to real. The term (karst hazards) is related to two other terms, used mostly in applied geosciences, particularly engineering geology – risk assessment and mitigation. Risk is the probability of an occurrence, and the consequential damages are defined as hazards. Risk assessment is the determination of quantitative or qualitative value of risk related to a concrete situation and a recognized hazard. Quantitative risk assessment requires calculations of two components: the magnitude of the potential loss and the probability that the loss will occur. Risk assessment is a step in a risk management. Mitigation may be defined as the reduction of risk to life and the environment by reducing the severity of collapse or subsidence, building subsidence-resistant constructions, restricting land use, etc.


Hypogene Höhlengenese: Aufsteigendes Grundwasser und Erdwärme als Antrieb der Entstehung labyrinthischer Höhlen in der Nördlichen Frankenalb und in anderen Teilen Bayerns, 2013,
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Glaser, Stefan

Die klassische Erklärung für die Entstehung von „epigenetischen“ bzw. „meteorischen“ Karsthöhlen ist, dass Niederschlagswasser versickert und im Karstgestein durch in der Atmosphäre oder im Boden erworbenes CO2 Hohlräume erweitert. Langfristig entstehen so unterirdische Gewässernetze mit Sammelsträngen, durch die das Wasser letztlich über Karstquellen wieder an die Oberfläche gelangt. Angetrieben wird der Prozess hauptsächlich von der Schwerkraft, unter deren Einfluss das Wasser fließt. Beim Besuch mancher Höhlen fällt es jedoch schwer, die Beobachtungen vor Ort in Einklang mit einer solchen Höhlenentstehung zu bringen. Insbesondere in der Nördlichen Frankenalb finden sich mehrere sehr labyrinthische Höhlen, die weder in den Raumformen noch in den Sedimenten oder in ihrer Gesamtanlage Spuren von ehemals fließendem Wasser erkennen lassen. Auch auf alternative Entstehungsmechanismen, die für atypische Höhlen in anderen Gebieten angenommen werden, gibt es in der Frankenalb keine Hinweise. Weder ist das Gebiet bekannt für hydrothermale Aktivität, noch für H2S oder CO2-Austritte aus dem Erdinneren. Der einzige in dem Gebiet bekannte Basaltgang liegt weit entfernt von den großen Höhlen. Wenn während dessen Entstehung ein erhöhter geothermischer Gradient und vulkanisches CO2 auftraten, so wären Auswirkungen hiervon vor allem im Nahbereich um den Basaltkörper zu erwarten


SALT KARST AND COLLAPSE STRUCTURES IN THE ANADARKO BASIN OF OKLAHOMA AND TEXAS, 2013,
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Johnson, K. S.

Permian bedded salt is widespread in the Anadarko Basin of western Oklahoma and the Texas Panhandle, where partial or total dissolution of the shallowest salt in some areas has resulted in subsidence and/or collapse of overlying strata. Groundwater has locally dissolved these salts at depths of 10–250 m. The distribution (presence or absence) of salt-bearing units, typically 80–150 m thick, is confirmed by interpretation of geophysical logs of many petroleum tests and a few scattered cores. Salt dissolution by ground water is referred to as “salt karst.”Chaotic structures, collapse features, breccia pipes, and other evidence of disturbed bedding are present in Permian, Cretaceous, and Tertiary strata that overly areas of salt karst. The dip of Permian and post-Permian strata in the region normally is less than one degree, mainly towards the axis of the Anadarko Basin. Where strata locally dip in various directions at angles of 5–25 degrees or more, and underlying salt units show clear evidence of dissolution, these chaotic dips must result (mostly, if not totally) from subsidence and collapse into underlying salt-dissolution cavities.Gypsum karst and resultant collapse of overlying strata have been proposed in many parts of the Anadarko Basin. However, the gypsum beds typically are only 1–6 m thick and more than 100 m deep, and cannot contribute to disruption of outcropping strata—except where they are within 10–20 m of the surface.Typical areas of disturbed bedding comprise several hectares, or more, with outcrops of moderately dipping strata—as though large blocks of rock have foundered and subsided into large underground cavities. Other examples of disturbed bedding are small-diameter breccia pipes, or chimneys, that extend vertically up from salt-karst cavities, through several hundred meters of overlying strata. The best evidence of these chimneys are collapsed blocks of Cretaceous strata, chaotically dropped some 50 m, or more, that are now juxtaposed against various Permian formations on the north flank of the Anadarko Basin. Any study of surface or shallow-subsurface geology in the Anadarko Basin must consider the influence of subsurface salt karst on the structure and distribution of overlying rocks


VARIATIONS IN EVAPORITE KARST IN THE HOLBROOK BASIN, ARIZONA, 2013,
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Neal J. T. , Johnson K. S. , Lindberg P.

At least six distinct forms of evaporite karst occur in the Holbrook Basin•depending considerably on overburden and/or bedrock type. Early Permian evaporites in the 300-m-thick Corduroy Member of the Schnebly Hill Formation include halite, sylvite, and anhydrite at depths of 215-250 m. Karst features result from collapse of overlying Permian and Triassic strata into underlying salt-dissolution cavities. Evaporite karst occurs primarily along the 100+ km-long dissolution front on the southwestern edge of the basin, and is characterized by numerous sinkholes and depressions generally coincident with the axis of the Holbrook Anticline•in reality a dissolution-collapse monocline. “The Sinks” comprise ~ 300 individual sinks up to 200 m across and 50 m deep, the main karst features along the dissolution front. Westerly along the dissolution front, fewer discrete sinkholes occur, and several breccia pipes are believed to be forming. Numerous pull-apart fissures, graben-sinks, sinkholes, and broad collapse depressions also occur.A newly recognized subsidence/collapse area of some 16 km2 occurs in the western part of the basin, northward from the extension of the Holbrook “anticline.” The Chimney Canyon area is some 12 km east of McCauley Sinks, a postulated breccia pipe exemplified in, and possibly manifested in at least four other closed depressions. Interferometric Synthetic Aperture Radar (InSAR) data of one depression shows active subsidence of ~4 cm/yr.Karst formation is ongoing, as shown by repeated drainage of Dry and Twin Lakes into newly opened fissures and sinkholes. These two playa lakes were enlarged and modified in recent years into evaporation 2impoundments for effluent discharge from a nearby pulp mill. Four major drainage events occurred within these playa reservoirs during the past 45 years, collectively losing more than 1.23 x107 m3 (10,000 acre-feet) of water and playa sediment. Drainage occurs through piping into bedrock joints in Triassic Moenkopi Formation (sandstone) in the bottom and along the margins of these playas. Effluent discharge has been discontinued into these playas, although recurring precipitation can fill the basins.


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