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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 Schichtfugenkarren is (german.) see bedding grike.?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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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 flank margin caves (Keyword) returned 29 results for the whole karstbase:
Showing 16 to 29 of 29
Caves as sea level and uplift indicators, Kangaroo Island, South Australia, 2009, Mylroie J. E. And Mylroie J. R.

Flank margin caves have been observed in Quaternary Bridgewater Formation eolianites on Kangaroo Island, South Australia. Horizons of flank margin cave development at 25 m, 30 m, and 35 m elevation demonstrate tectonic uplift of tens of meters during the Quaternary, as the cave elevations are higher than any reported Quaternary glacioeustatic sea-level highstand. Distinct cave horizons indicate that episodic uplift was possible. Wave-cut notches at Hanson Bay, at 30 to 35 m elevation, also support the interpretation from caves that relative sea level was once at the ,30-m- elevation range. Admirals Arch, previously presented as forming solely by wave erosion, is a flank margin cave breached and modified by wave erosion. Point Ellen contains a Late Pliocene subtidal carbonate unit that formed within the reach of wave base, was uplifted and cliffed by wave processes, and then was karstified before being buried by Quaternary Bridgewater Formation eolianites. A possible flank margin cave developed at Point Ellen at 3 m above modern sea level is consistent with earlier interpretations of notching of the nearby coast at a similar elevation during the last interglacial sea-level highstand (MIS 5e); and therefore, no tectonic uplift in the last 120 ka. In contrast, the tafoni of Remarkable Rocks present a cautionary note on evidence of cave wall morphological characteristics as proof of dissolutional origin.

Plava Grota, Cres Island, Croatia, is a flank margin cave developed in a coastal setting in talus breccia facies. The internal cave geometry of small entrances, intersecting adjacent chambers, remnant dissolutional bedrock pillars, and low arches matches diagnostic features used to separate flank margin caves from epigenic stream caves on one hand, and sea caves on the other. Plava Grota is found, along with adjacent smaller caves, solely in a breccia facies that is most probably of Pleistocene age. This breccia is comprised of clasts derived from diagenetically mature, or telogenetic, Cretaceous carbonate rocks. The clasts are loosely cemented by vadose calcite cements. The breccia facies provide a three-dimensional porosity and permeability structure that behaves hydraulically in a manner similar to the high primary porosity and permeability of young eogenetic carbonate rocks in settings such as the Bahamas or Puerto Rico, and the many flow paths found in highly-tectonized telogenetic carbonate rocks in New Zealand. Plava Grota is the first described flank margin cave from the coastal carbonate rocks of the Adriatic Sea. According to present sea-level position in relation to the cave, fresh-water springs in and adjacent to the cave, general tectonic subsidence of the area and Quaternary eustatic sea-level fluctuations, we propose the hypotheses that the cave was primarily formed during the MIS 5e sea-level highstand.

Coastal cave in Bahamain eolian calcarenites: Differentiating between sea caves and flank margin caves using quantitative morphology, 2010, Waterstrat, Willapa J. , Mylroie, John E. , Owen, Athena M. And Mylroie, Joan R.

Coastal areas on carbonate islands commonly contain two types of caves: sea caves developed by wave erosion processes, and flank margin caves developed by dissolution at the edge of the fresh-water lens. Differentiating sea caves and flank margin caves in coastal settings is important, but can it be done reliably and quantitatively? Current methods use the degree of intricate wall-rock dissolution and the presence or absence of dense calcite speleothems to separate the two cave types. This study reports how analysis of cave maps creates three separate tools to differentiate coastal caves: area to perimeter ratio, entrance width to maximum width ratio, and rectangle short axis to long axis ratio. The study also presents some of the first sea cave data from eogenetic carbonate islands, specifically eolian calcarenites. The morphological and geometrical comparisons between Bahamian flank margin cave and sea cave maps using the three tools allows the two cave types to be statistically differentiated. The Bahamian sea cave data were also compared to sea cave data from California and Maine to demonstrate that Bahamian sea caves have a unique quantitative signature based on the youth and homogeneity of the host eolian calcarenite rock. The Bahamian sea cave data also indicate that sea cave formation may not be solely determined by differential rock weaknesses, as reported in the literature, but may also be a result of wave dynamics such as constructive interference.

Bell Hole Origin: Constraints on Developmental Mechanisms, Crooked Island, Bahamas, 2011, Birmingham Andrew N. , Mylroie Joan R. , Mylroie John E. , Lace Michael J.

Bell holes are vertical, cylindrical voids, higher than they are wide, with circular cross sections and smooth walls found in the ceilings of dissolutional caves primarily from tropical and subtropical settings. They range in size from centimeter to meters in height and width. The origin of bell holes has been controversial, with two proposed categories: vadose mechanisms including bat activity, condensation corrosion, and vadose percolation; and phreatic mechanisms including degassing and density convection.
Crooked Island, Bahamas has a number of caves with bell holes of unusual morphology (up to 7 m high and 1.5 m in diameter), commonly in tight clusters, requiring significant bedrock removal in a small area. In many cases, numerous bell holes are open to the surface, which requires that up to a meter or more of surface denudation has occurred since the bell hole first formed.
Surface intersection has little impact on the phreatic mechanisms, which were time limited to cave genesis from 119 to 131 ka ago, but greatly reduces the time window for later vadose mechanisms, which need to have been completed before bell hole intersection by surface denudation.
The Crooked Island observations suggest that bell hole development occurred syngenetically with flank margin cave development under phreatic conditions. Because flank margin caves develop under slow flow conditions, vertical convection cell processes are not disrupted by turbulent lateral flow and bell holes formed as a vertical phreatic dissolution signature.

Fresh-water lens anisotropy and flank margin cave development, Fais Island, FSM, 2011, Mylroie John E. , Mylroie Joan R. , Jenson John W. , Maccracken Rob

Fais Island, which lies about 200 km east of Yap, Federated States of Micronesia, in the Caroline Islands of the Western Pacific Ocean, is a small uplifted carbonate platform. Modern fresh water lens discharge is concentrated where high-relief cliffs extend seaward beyond the beach and reef flats. Fresh water flow from the beaches and reef flats is small to insignificant. Flank margin caves are also concentrated in these headlands and are conspicuously absent in the vertical cliffs inland of beach and reef flat areas. The original porosity in the pre-Holocene carbonate rocks of Fais has been rearranged into high-permeability flow
systems by repeated exposure to the fresh water lens. The older headlands that extend past the lower permeability beaches and reef flats, conduct water from the lens to the sea. At the same time, flank margin cave development between headlands was diminished by the lack of fresh water lens discharge in those areas. A large closed-contour depression containing a fresh water pool looks at first sight like a sinkhole, but is in fact, an ancient well dug into terraced Holocene sands that infill a reentrant in a paleo-sea cliff. The low relative permeability of these sands creates a more substantial fresh water lens than is available elsewhere on the island.

Eolianites and Karst Development in the Mayan Riviera, Mexico, 2011, Kelley Kristin N. , Mylroie John E. , Mylroie Joan R. , Moore Christopher M. , Collins Laura R. , Ersek Lica, Lascu Ioan, Roth Monica J. , Moore Paul J. , Passion Rex, Shaw Charles

Coastal Quintana Roo, Mexico, including islands such as Cozumel and Isla Mujeres, contains numerous ridges of Quaternary eolian calcarenite in two packages, one Pleistocene and one Holocene. The Pleistocene eolianites are recognizable in the field by well-developed terra rossa paleosol and micritic crust on the surface, containing a fossil epikarst. The foreset beds of these eolianites commonly dip below modern sea level, and fossilized plant root structures are abundant. The Holocene
eolianites lack a well-developed epikarst, and have a calcernite protosol on their surfaces. The degree of cementation, and the grain composition, are not reliable indicators of the age of Quaternary eolianites.

The Pleistocene eolianites have been previously described (e.g. Ward, 1997) as exclusively regressive-phase eolianites, formed by the regression during the oxygen isotope substages (OIS) 5a and 5c. However, certain eolianites, such as those at Playa Copal, contain flank margin caves, dissolution chambers that form by sea water/fresh water mixing in the fresh-water lens. For such mixing dissolution to occur, the eolianite must already be present. As the flank margin caves are found at elevations of 2-6 m above current sea level, the caves must have developed during the last interglacial sea-level highstand, and the eolianites could not have formed on the regression from that or younger highstands. Therefore the eolianites must be transgressive-phase
eolianites developed at the beginning of the last interglacial sea-level highstand, or either transgressive- or regressive-phase eolianites from a previous sea-level highstand that occurred earlier in the Pleistocene. There is no field evidence of oxygen isotope substage 5c or 5a eolianites as suggested by Ward (1997).

Most coastal outcrops show classic regressive–phase Pleistocene eolianites as illustrated by complex and well-developed terra rossa paleosols and epikarst, and dense arrays of fossilized plant roots. However, in addition to flank margin caves, other evidence of transgressive-phase eolianites includes notches in eolianites on the west side of Cozumel, with subtidal marine facies onlapping the notches. The absence of a paleosol between those two units indicates that the eolianite is a transgressive-phase deposit from the last interglacial. All Holocene eolianites are, by definition, transgressive-phase units.

Comment on Coastal Caves in Bahamian Eolian Calcarenites: Differentiating Between Sea Caves and Flank Margin Caves Using Quantitative Morphology, 2011, Curl, R.

Comment on Coastal Caves in Bahamian Eolian Calcarenites: Differentiating Between Sea Caves and Flank Margin Caves Using Quantitative Morphology, 2011, Mixon, B.

Coastal Caves, 2012, Mylroie, John E.

Coastal caves are, by definition, caves that form along the coast as a result of the interaction of terrestrial and marine processes. Sea level can fluctuate, both globally as well as locally, and therefore the site of coastal cave development changes through time. Coastal caves form for two main reasons. First, wave and salt attack on any rocky coast can excavate simple hollows and chambers, called sea caves or littoral caves, in a variety of rock materials. Second, on limestone coasts, the dissolution of the rock by the mixing of freshwater and seawater can create complex cave systems called flank margin caves. Blue holes also form in limestone coastal regions from a variety of processes. Safe cave exploration in any environment requires training and preparation; while flank margin caves are relatively safe, the exploration of sea caves and blue holes can be extremely dangerous, even for those with years of experience.

Flank margin caves in carbonate islands and the effects of sea level., 2013, Mylroie J. E. , Mylroie J. R.

Flank margin caves form in the diffuse flow field of the distal margin of the freshwater lens on carbonate islands and coasts. Dissolution is governed by superposition of mixing zones at the top and bottom of the lens. Flow velocities in the lens margins and organic decay at the lens boundaries enhance dissolution. These caves grow from isolated initiation points in the lens into chambers that amalgamate to form complex, vertically restricted, globular-chamber complexes. The caves and their deposits accurately represent sea-level position and paleoclimate but must be successfully differentiated from sea caves and other pseudokarst features..


Coastal karst areas often host many indices of past sea level changes, such as marine terraces, fossiliferous sediments, tidal notches and coastal caves. Tectonic movements can then displace these ancient coastlines vertically. The interplay between rising or falling sea level and uplifting or subsidence can be very complex and difficult to unravel. The combination of a detailed knowledge of marine terraces and the study of some flank margin caves located at various altitudes have allowed to reconstruct the speleogenetic history of the coastal plain of Cornino-Custonaci (NW Sicily). Along the centraleastern coast of Sardinia, instead, the detailed study of the Fico Cave has allowed to recognise it as a flank margin cave developed on five levels, related to Pleistocene sea level highstands. These studies show that this type of mixing corrosion caves is much more widespread than previously thought also in telogenetic limestones. These caves, being excellent sea level markers, might help coastal geomorphologists to understand more on both sea level rise and fall and tectonic movements in coastal areas.



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.

Hypogene Cave Morphologies. Selected papers and abstracts of the symposium held February 2 through 7, 2014, San Salvador Island, Bahamas, 2014,

This new electronic publication is Special Publication 18 from the Karst Waters Institute, consisting of selected papers and abstracts for the Hypogene Cave Morphologies symposium held February 2 - 7, 2014, on San Salvador Island, The Bahamas. The main thematic activities of the conference were to examine and discuss the unique cave morphologies and speleogens associated with hypogene caves, from the scale of 100 km+ cave maps down to centimeter size wall rock shapes and forms. Hypogene caves can be argued to represent a laminar flow regime that is quite different from the turbulent flow found in epigenic stream caves coupled to surface hydrology. Can these morphologies be uniquely characterized to identify hypogene caves? What effect do these laminar flow regimes have on geochemical models of dissolution drive in hypogene settings? Do flank margin caves fall in the hypogene flow environment?

Uplifted flank margin caves in telogenetic limestones in the Gulf of Orosei (Central-East Sardinia—Italy) and their palaeogeographic significance, 2015, D'angeli Ilenia Maria, Sanna Laura, Clazoni Claudio, De Waele Jo

Thiswork reports the results of geomorphological observations carried out in the coastal Fico Cave and surrounding areas (Baunei, Central East Sardinia) in the Gulf of Orosei. A tidal notch, generally believed to be of Eemian (MIS 5e) age, is barely visible at 8.5 above present sea level (asl), some metres below the main entrance of the cave. Old cave passages, now partially opened by cliff retreat and parallel to the coastline, are clearly visible at around 14 m asl and correspond to the main level of Fico Cave. Two more notches are located higher, at 22 and 50 m asl. Fico Cave itself is composed of at least 6 clearly distinguished more or less horizontal levels (−10 m below present sea level (bsl), and +14, +22, +40, +50, and +63 m asl), independent of the stratal dip, arguing for a sea-level, and hence, fresh-water lens control. Cave passages develop along main fractures more or less parallel to the coastline and never extend landward for more than 150 m, mostly ending blindly, or diminishing in their dimensions progressively landward. Most passages only contain clay deposits, lacking fluvial or marine sediments or typical fluvial erosion morphologies (i.e. scallops).

It is suggested from this body of evidence that Fico Cave was formed in the coastal mixing zone along major discontinuities during several Quaternary interglacial periods, when sea level was high and relatively stable for enough time to develop large dissolutional voids. The geomorphological observations indicate the main +14 m asl level of the cave to have formed during MIS 9, and was heavily reworked during MIS 5, while the higher levels are relative to older interglacial highstands that occurred between 1 Ma and 325 ka. The small active branch developed below present sea level has formed during MIS 7 (225 ka). These observations shed new light on the position of the MIS 5e highstand markers in this area of the coast, much higher than previously thought.

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