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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. ...

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That pearl is see cave pearl.?

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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 karst development (Keyword) returned 131 results for the whole karstbase:
Showing 106 to 120 of 131
Paleokarst of the USA: A Brief Review, 2011, Palmer A. N. , Palmer M. V.

Paleokarst consists of solutional features from a prior geomorphic phase that have been preserved by  burial or by a substantial change in local environment. The two major paleokarst horizons in North  America are of Early-Middle Ordovician (post-Sauk) age and Mississippian-Pennsylvanian (post-Kaskaskia) age. There are also several less extensive paleokarst zones. They all differ in detail but  typically include remnants of surface karst features, caves, breccias, hypogenic porosity, and related  mineral suites. In places they provide high-permeability zones significant to water supply, or serve as  hosts to petroleum, ores, and later karst development. Studies of paleokarst give significant evidence for  past geologic and hydrologic conditions, both surficial and deep seated.


Using Geographic Information System to Identify Cave Levels and Discern the Speleogenesis of the Carter Caves Karst Area, Kentucky, 2011, Peterson E. , Dogwiler T. , Harlan L.

Cave level delineation often yields important insight into the speleogenetic history of a karst system. Various workers in the Mammoth Cave System (MCS) and in the caves of the Cumberland Plateau Karst (CPK) have linked cave level development in those karst systems with the Pleistocene evolution of the Ohio River. This research has shown that speleogenesis was closely related to the base level changes driven by changes in global climate. The Carter Caves Karst (CCK) in northeastern Kentucky has been poorly studied relative to the MCS to the west and the CPK karst to the east. Previously, no attempt had been made to delineate speleogenetic levels in the CCK and relate them to the evolution of the Ohio River. In an attempt to understand cave level development in CCK we compiled cave entrance elevations and locations. The CCK system is a fluviokarst typical of many karst systems formed in the Paleozoic carbonates of the temperate mid-continent of North America. The CCK discharges into Tygarts Creek, which ultimately flows north to join the Ohio River. The lithostratigraphic context of the karst is the Mississippian Age carbonates of the Slade Formation. Karst development is influenced by both bedding and structural controls. We hypothesize that cave level development is controlled by base level changes in the Ohio River, similar to the relationships documented in MCS and the karst of the Cumberland Plateau The location and elevation of cave entrances in the CCK was analyzed using a GIS and digital elevation models (DEMs). Our analysis segregated the cave entrances into four distinct elevation bands that we are interpreting as distinct cave levels. The four cave levels have mean elevations (relative to sea level) of 228 m (L1), 242 m (L2), 261 m (L3), and 276 m (L4). The highest level—L4—has an average elevation 72 m above the modern surface stream channel. The lowest level—L1—is an average of 24 m above the modern base level stream, Tygarts Creek. The simplest model for interpreting the cave levels is as a response to an incremental incision of the surface streams in the area and concomitant adjustment of the water table elevation. The number of levels we have identified in the CCK area is consistent with the number delineated in the MCS and CPK. We suggest that this points toward the climatically-driven evolution of the Ohio River drainage as controlling the speleogenesis of the CCK area 


U.S. Geological Survey Karst Interest Group Proceedings, Fayetteville, Arkansas, April 2629, 2011/ Scientific Investigations Report 20115031, 2011, Av

Karst aquifer systems are present throughout parts of the United States and some of its territories and are developed in carbonate rocks (primarily limestone and dolomite) that span the entire geologic time frame. The depositional environments, diagenetic processes, and post-depositional tectonic events that form carbonate rock aquifers are varied and complex, involving both biological and physical processes that can influence the development of permeability. These factors, combined with the diverse climatic regimes under which karst development in these rocks has taken place result in the unique dual or triple porosity nature of karst aquifers. These complex hydrologic systems often present challenges to scientists attempting to study groundwater flow and contaminant transport.
The concept for developing a Karst Interest Group evolved from the November 1999 National Groundwater Meeting of the U.S. Geological Survey (USGS), Water Resources Division. As a result, the Karst Interest Group was formed in 2000. The Karst Interest Group is a loose-knit grass-roots organization of USGS employees devoted to fostering better communication among scientists working on, or interested in, karst hydrology studies.
The mission of the Karst Interest Group is to encourage and support interdisciplinary collaboration and technology transfer among USGS scientists working in karst areas. Additionally, the Karst Interest Group encourages cooperative studies between the different disciplines of the USGS and other Federal agencies, and university researchers or research institutes.
This fifth workshop is a joint workshop of the USGS Karst Interest Group and University of Arkansas HydroDays workshop, sponsored by the USGS, the Department of Geosciences at the University of Arkansas in Fayetteville. Additional sponsors are: the National Cave and Karst Research Institute, the Edwards Aquifer Authority, San Antonio, Texas, and Beaver Water District, northwest Arkansas. The majority of funding for the proceedings preparation and workshop was provided by the USGS Groundwater Resources Program, National Cooperative Mapping Program, and the Regional Executives of the Northeast, Southeast, Midwest, South Central and Rocky Mountain Areas. The University of Arkansas provided the rooms and facilities for the technical and poster presentations of the workshop, vans for the field trips, and sponsored the HydroDays banquet at the Savoy Experimental Watershed on Wednesday after the technical sessions.


Karst and caves of headstreams of the Lena River, 2011, Philippov V. M. , Filippov A. G. , Indyukov A. E.

Karst phenomena of headstreams of the Lena River in Eastern Siberia between junctions of the Zolotokan Creek and Chanchur River are described in the paper. Wide spreading of karst is determined by: areal occurrence of marine carbonate rocks of the Lower and Middle Cambrian, their monoclinal bedding, increased tectonical fracturing of karstiferous rocks, relatively high roughness of surface topography, flattened dividing ranges, relatively humid climate (precipitation 400-500 mm per year), and long history of continental regime of the area. The relics of ancient gently sloped river valleys at dividing ranges are the most karstified. There is no surface drainage in their limits, and groups of dolines up to 40-80 individuals per square kilometer are common. Karst development determines an existence of vast meadows covered with the dwarf birch, reindeer moss and herbs (Trollius asiaticus Scutellaria baialensis, Rhodiola rosea, Veratrum lobelianum, Gentiana sp., Allium sp. .) among stocked coniferous taiga at the altitude of 1080-1150 m a.s.l. at the watershed divides of the Lena and Levaya Tongoda rivers (Mongolian Steppe Stow), and Lena and Pankucha-2nd rivers. On the rest of the territory, dolines do not form large groups, but they occur as isolated individuals or scattered clusters consisting of 3 to 5 individuals. Karst dry valleys are widely spread. Their total length is not less than 397 km, and 126 km of them belongs to the watershed of the Yukhta-1st River. Residual hills having morphology of pillars, towers and ridges were observed. Descriptions of two karst caves and two crevice caves are given.

 


The nature and distribution of flowing features in a weakly karstified porous limestone aquifer, 2012, Maurice L. D. , Atkinson T. C. , Barker J. A. , Williams A. T. , Gallagher A. J.

The nature and distribution of flowing features in boreholes in an area of approximately 400 km2 in a weakly karstic porous limestone aquifer (the Chalk) was investigated using single borehole dilution tests (SBDTs) and borehole imaging. One-hundred and twenty flowing features identified from SBDTs in 24 boreholes have densities which decrease from _0.3 m_1 near the water table to _0.07 m_1 at depths of more than 40 m below the water table; the average density is 0.20 m_1. There is some evidence of regional lithological control and borehole imaging of three boreholes indicated that most flowing features are associated with marls, hardgrounds and flints that may be developed at a more local scale. Borehole imaging also demonstrated that many flowing features are solutionally enlarged fractures, suggesting that even in carbonate aquifers where surface karst is developed on only a small scale, groundwater flow is still strongly influenced by dissolution. Fully connected solutional pathways can occur over 100s, sometimes 1000s of metres. However, conduits, tubules and fissures may not always be individually persistent along a flowpath, instead being connected together and also connected to unmodified fractures to create a relatively dense network of voids with variable apertures (<0.1 cm to >15 cm). Groundwater therefore moves along flowpaths made up of voids with varying shape and character. Local solutional development of fractures at significant depths below the surface suggests that mixing corrosion and in situ sources of acidity may contribute to solutional enhancement of fractures. The study demonstrates that single borehole dilution testing is a useful method of obtaining a large dataset of flowing features at catchment-regional scales. The Chalk is a carbonate aquifer with smallscale surface karst development and this study raises the question of whether other carbonate aquifers with small-scale surface karst have similar characteristics, and what hydrological role small-scale dissolutional features play in highly karstic aquifers.


Hypogene karst of Simferopol (Crimean fore-mountains) and its evolution, 2012, Amelichev G. N. , Dmitrieva A. Y. , Samokhin G. V.

In the limits of the urbanized territories of the fore-mountain Crimea, the amount of emergency situation caused by karst grows rapidly. At the same time indexes of intensity of modern karst processes are low, and environmental conditions are barely favourable for karst development. This disparity is settled on the basis of application of new ideas and concepts of geology, hydrogeology and speleogenesis, which have been integrated in domestic karstology relatively recently. In Simferopol, the capital of Crimea, features of relict hypogene karst are revealed, which are powerful stimulus of development of other negative exogeodynamic processes. The morfologo-genetic and age-dependent re-interpretation of karst features is performed. Superficial and underground forms are described. The article highlights main stages of karst evolution in the city. The growth of karst hazards in Simferopol is related to antropogenic activity, resulting in activation of relict hypogene karst features.


Quaternary alluvial sinkholes: Record of environmental conditions of karst development, examples from the Ebro Basin, Spain , 2012, Soriano M. A. , Luzon A. , Yuste A. , Pocovı, A. , Perez A. , Simon J. L. , Gil H.

The central Ebro Basin is an exceptional region for studying karstification through time and under different environmental conditions, as sinkholes have been developing since the Early Pleistocene. Knowledge of active sinkholes is complemented with research on paleosinkholes and contemporary deposits. Sedimentological, mineralogical, geomorphological and structural approaches permit interpretation of the natural environmental conditions that favored karst in the past and the main genetic mechanisms involved. The sedimentary features of Pleistocene terraces indicate that they were deposited by a gravel braided fluvial system characterized by higher water and sediment availability than today, probably related to meltwater flows coming from glaciated source areas, mainly in the Pyrenees. Genesis of paleosinkholes was mainly linked to this high water supply. Some of them acted as small lakes where fine sediments are exceptionally well conserved to give clues about environmental conditions. The neoformation of palygorskite and sepiolite suggests arid to semiarid climatic conditions, in agreement with the idea of cold glacial episodes. During Pleistocene times, development of sinkholes was influenced by tectonics. Currently, the genesis and evolution of numerous sinkholes are also influenced by water supplies from human activities such as irrigation or urbanization, sharply changing the nearly steady state exhibited in the past


Karst and caves of headstreams of the Lena River, 2012, Philippov V. M. , Filippov A. G. , Indyukov A. E.

Karst phenomena of headstreams of the Lena River in Eastern Siberia between junctions of the Zolotokan Creek and Chanchur River are described in the paper. Wide spreading of karst is determined by: areal occurrence of marine carbonate rocks of the Lower and Middle Cambrian, their monoclinal bedding, increased tectonical fracturing of karstiferous rocks, relatively high roughness of surface topography, flattened dividing ranges, relatively humid climate (precipitation 400-500 mm per year), and long history of continental regime of the area. The relics of ancient gently sloped river valleys at dividing ranges are the most karstified. There is no surface drainage in their limits, and groups of dolines up to 40-80 individuals per square kilometer are common. Karst development determines an existence of vast meadows covered with the dwarf birch, reindeer moss and herbs (Trollius asiaticus, Scutellaria baialensis, Rhodiola rosea, Veratrum lobelianum, Gentiana sp., Allium sp. .) among stocked coniferous taiga at the altitude of 1080-1150 m a.s.l. at the watershed divides of the Lena and Levaya Tongoda rivers (Mongolian Steppe Stow), and Lena and Pankucha-2nd rivers. On the rest of the territory, dolines do not form large groups, but they occur as isolated individuals or scattered clusters consisting of 3 to 5 individuals. Karst dry valleys are widely spread. Their total length is not less than 397 km, and 126 km of them belongs to the watershed of the Yukhta-1st River. Residual hills having morphology of pillars, towers and ridges were observed. Descriptions of two karst caves and two crevice caves are given.


Geomorphogenesis of astructural slopes of the Inner Range of the Mountainous Crimea: the role of hypogenic karst in the formation and retreat of cliffs, 2012, Tymokhina . . , Klimchouk A. B. , Amelichev G. M.

In geomorphogenesis of the fore-mountain region, a leading role is played by the processes of dismemberment of «shielding» limestone layers of the monoclinal stratified structure, and slope processes in the intervals of rocky limestone utcrops. Their main pre-condition for the latter is hypogene karst development which preceded the modern relief and controlled its formation. Karstified fracture-karst zones, 100 to 400 m wide, in the Cretaceous-Paleogene strata controlled the entrenchment of valleys in the limestone layers. The basic elements of hypogenic karst structures, which forms their spatial framework, are subvertical
fracture-karst conduits (karst «rifts»). Dissection of limestone layers along vertical fracture-karst rift conduits initially set the cliff-like shape of valleys slopes, and presence of such rift conduits in the rear of cliffs of already incised valleys determines the mechanisms of cliff retreat, with the maintenance of verticality, and controls position and configuration of segments of cliffs. A dominant slope process in the intervals of limestones is block toppling, whereas blocks become separated mainly along remaining
fracture-karst conduits in rearward parts of cliffs. Hypogenic sculptural morphology is displayed in the exposed walls of the fracture-karst conduits, which determines the originality and nomenclature of morphology of limestone cliffs of the Inner Range. In those areas of slopes where position of cliffs has stabilized for considerable time due to absence of new lines of block detachment in the rear, weathering becomes a significant process in the morphogenesis of surfaces. Slopes lose their verticality and acquire
the smoothed rims. Specific hypogenic sculptural morphology of cliffs is being destroyed on such slopes. The finding about control of slope processes in limestones by hypogenic fracture-karst structures gives new important criteria for the slope condition assessment and prognosis of hazardous collapses and rockfalls in the limits of the Internal Range 


Development of a deep karst system within a transpressional structure of the Dolomites in north-east Italy, 2013, Sauro Francesco, Zampieri Dario, Filipponi Marco

The Piani Eterni karst system is one of the longest and deepest caves of Italy situated in the southern sector of the Dolomiti mountain range. The area where the cave was formed displays peculiar structural settings confined in a tectonic transpressive corridor between two regional thrusts (Belluno and Valsugana). During Miocene uplift of the range the inheritance of Mesozoic structures led to the formation of a deep and wide upward-branching flower (or palm tree) structure cutting the carbonate sequence and exposing the surrounding surface to karst processes after erosion. The relative lowering of the hydrologic base level, due both to the uplift of the area and then to the carving of deep glacial valleys in the Quaternary, allowed the formation of paleo-phreatic conduits at subsequently deeper levels, interconnected by vadose shafts and canyons.

This work gives a detailed tectonic interpretation of the transpressive structure and picks out the tectonic features most favorable to the karst development. A detailed statistical analysis of the distribution and orientation of the karst conduits was performed using 31 km of 3D surveys showing that the development of the cave was strictly guided by a few favorable surfaces of stratigraphic and tectonic origin. These features are known in the literature as inception horizons and tectonic inception features, respectively. Cave levels are usually related to lithologic favorable conditions associated with standings of the paleo-water table. Here we suggest that some tectonic surface geometries could have led to the opening of voids in the active tectonic phase leading to the formation of the original proto-conduit network. Different types of tectonic inception features identified in the cave were described in terms of geometry and kinematics. Tensional fractures, as well as fault plane undulations and flexural slip surfaces between beds, are described as the most favorable tectonic surfaces for the development of the conduits. Finally, we discuss why transpressional settings and related flower structures in soluble rocks can enhance the karst process allowing the formation of huge and deep karst systems.


Tower karst and cone karst, 2013, Zhu X. , Zhu D. , Zhang Y. , Lynch E. M.

Cone karst and tower karst are spectacular types of tropical/subtropical karst formed under conditions of intense karstification, and occurring primarily in China, Vietnam, Cuba, Jamaica, Puerto Rico, and Java. The cone-tower karst system is classified into two basic types: fengcong-fenglin karst developed in hard, fissure-porosity rocks, and cockpit-mogotes karst in soft, high primary porosity carbonates. Key factors in the development of cone-tower karst include tropical or subtropical climate with abundant precipitation, tectonic uplift and base-level lowering, relatively pure and thick carbonate lithology, gentle anticline/syncline structures, allogenic input and through rivers. Differentiation into the cone (fengcong/cockpit) or tower (fenglin/mogotes) subtypes is strongly influenced by surface flow and the thickness of the vadose zone. Basic features of cone-tower karst, formation, and global distribution are discussed, with special emphasis on fengcongfenglin karst and the role of point infiltration, linear infiltration, and surface flow. The simultaneous (as opposed to sequential) evolution of fengcong karst and fenglin karst is explained by systematically analyzing the karst development, as well as the formation rate and age of fengcong-fenglin karst


Evolution of Intrastratal Karst and Caves in Gypsum, 2013, Klimchouk, A. B.

The term ‘intrastratal karst’ denotes a series of evolutionary karst types corresponding to successive stages of karst developmentin a soluble rock while it moves back to exposure after being buried by younger strata. The major boundaryconditions, the overall circulation pattern, and extrinsic factors and intrinsic mechanisms of karst development appear tochange considerably between the stages, resulting in characteristic styles of cave development and surface karst morphology,particularly distinct in case of gypsum karst.As gypsum is much more soluble than carbonates, it does not survive long in outcrops beyond arid areas. Wheregypsum is exposed to the surface with no substantial karstification formed during various stages of reburial, the developmentof epigene solution porosity in this rock is hindered due to the fast dissolution, being limited to flow paths in whichthe breakthrough conditions can be attained quickly. However, karst processes in gypsum develop extensively in intrastratalkarst settings, with inheritance from the deep-seated stage through the denuded one. Karstification may commence in anystage of intrastratal development, and during the next successive stage, the process, although in changed conditions, will beaffected significantly by the preformed solution porosity. Speleogenesis in deep-seated gypsum karst is exclusively hypogene.In subjacent karst, both hypogene and epigene speleogenesis may operate depending on the locally prevailing flowregime, but hypogene speleogenesis still dominates. In entrenched and denuded karst types, speleogenesis is overwhelminglyepigenic, but it is greatly facilitated by the presence of solution porosity inherited from the previous stages.Diverse and expressive karst landforms related to subsurface conduits evolve through different stages of the intrastratal karstdevelopment.The subsidence hazard in regions underlain by gypsum differs substantially between the karst types, so that one canobtain a kind of integrated general hazard assessment by classifying a given individual karst according to its evolution state.In general, various types of intrastratal karst, subjacent karst in particular, are the most potent in generating subsidence problems, whereas exposed karst types, particularly open karst, are the least prone to subsidence


Hydrogeology of gypsum Formations in Iran, 2013, 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.


KARST DEVELOPMENT IN THE GLACIATED AND PERMAFROSTREGIONS OF THE NORTHWEST TERRITORIES, CANADA, 2013, Ford Derek

 

The Northwest Territories of Canada are ~1.2 million km2 in area and appear to contain a greater extent and diversity of karst landforms than has been described in any other region of the Arctic or sub-Arctic. The Mackenzie River drains most of the area. West of the River, the Mackenzie Mountains contain spectacular highland karsts such as Nahanni (Lat. 62° N) and Canol Road (Lat. 65° N) that the author has described at previous International Speleological Congresses. This paper summarizes samples of the mountain and lowland karst between Lats. 64–67° N that are located east of the River. The Franklin Mountains there are east-facing cuestas created by over-thrusting from the west. Maximum elevations are ~1,000 m a.s.l., diminishing eastwards where the cuestas are replaced by undeformed plateaus of dolomite at 300–400 m asl that overlook Great Bear Lake. In contrast to the Mackenzie Mountains (which are generally higher) all of this terrain was covered repeatedly by Laurentide Continental glacier ice flowing from the east and southeast. The thickness of the last ice sheet was >1,200 m. It receded c.10,000 years ago. Today permafrost is mapped as “widespread but discontinuous” below 350 m a.s.l. throughout the region, and “continuous” above that elevation. The vegetation is mixed taiga and wetlands at lower elevations, becoming tundra higher up. Access is via Norman Wells (population 1,200), a river port at 65° 37’N, 126° 48’W, 67 m a.s.l.: its mean annual temperature is -6.4 °C (January mean -20 °C, July +14 °C) and average precipitation is ~330 mm.y-1, 40 % falling as snow. In the eastern extremities a glacial spillway divides the largest dolomite plateau into “Mahony Dome” and “Tunago Dome”. The former (~800 km2) has a central alvar draining peripherally into lakes with overflow sinkholes, turloughs, dessicated turloughs, and stream sinks, all developed post-glacially in regular karst hydrologic sequences. Tunago Dome is similar in extent but was reduced to scablands by a sub-glacial mega-flood from the Great Bear basin; it is a mixture of remnant mesas with epikarst, and wetlands with turloughs in flood scours. Both domes are largely holokarstic, draining chiefly to springs at 160–180 m a.s.l. in the spillway. The eastern limit of overthrusting is marked by narrow ridges created by late-glacial hydration of anhydrite at shallow depth in interbedded dolostones and sulphate rocks. Individual ridges are up to 60 km long, 500–1,000 m wide, 50–250 m in height. They impound Lac Belot (300 km2), Tunago Lake (120 km2) and many lesser lakes, all of which are drained underground through them. In the main overthrust structures, the Norman Range (Franklin Mountains) is oriented parallel with the direction of Laurentide ice flow. It displays strongly scoured morphology with elongate sinkholes on its carbonate benches. In contrast, the Bear Rock Range is oriented across the ice flow, has multiple cuestas, is deeply furrowed and holokarstic but preserves pinnacle karst on higher ground due to karst-induced polar thermal (frozen-down) conditions at the glacier base there.


FLANK MARGIN CAVES ON A PASSIVE CONTINENTAL MARGIN: NARACOORTE AND OTHER SOUTHERN AUSTRALIAN EXAMPLES, 2013, White Susan

 

Flank margin caves (FMC) have been predominantly described on carbonate islands such as in the Bahamas or the Marianas, using the Island Karst Model. This model has been used to explain karst development on young carbonate islands with poorly cemented eolianites, which differ substantially from continental karst, formed in well cemented limestones. Karst on continental margins especially the southern Australian coast, are not in well cemented telogenic rocks but in highly porous, highly permeable marine and eolian calcarenites. The gradual uplift over the past 50 Ma of the southern edge of the continent has resulted in Flank Margin Caves which formed in a coastal setting, being positioned significantly further inland and reflect the neotectonics of the Southern Australian passive continental margin rather than solely the Pleistocene glacio/eustatic sealevel fluctuations. The inter-relationship of tectonic setting, the distinctive characteristics of FMC and the speleogenesis of coastal karst assists in the understanding of the karst landscape evolution of significant karst areas of southern Australia.


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