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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 bed is 1. a layer in sedimentary rocks; a stratum [10]. 2. a sedimentary deposit of relatively small thickness and great areal extent, separated by bedding planes from over- and underlying deposits [16].?

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


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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 beach (Keyword) returned 26 results for the whole karstbase:
Showing 16 to 26 of 26
Eine bisher unbeachtet gebliebene sterreichische Hhlenbriefmarke, 2001,
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Mayer, A.

Seismic stratigraphy of Late Quaternary deposits from the southwestern Black Sea shelf: evidence for non-catastrophic variations in sea-level during the last ~10[punctuation space]000 yr, 2002,
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Aksu Ae, Hiscott Rn, Yasar D, Isler Fi, Marsh S,
Detailed interpretation of single channel seismic reflection and Huntec deep-tow boomer and sparker profiles demonstrates that the southwestern Black Sea shelf formed by a protracted shelf-edge progradation since the Miocene-Pliocene. Five seismic-stratigraphic units are recognized. Unit 1 represents the last phase of the progradational history, and was deposited during the last glacial lowstand and Holocene. It is divided into four subunits: Subunit 1A is interpreted as a lowstand systems tract, 1B and 1C are interpreted as a transgressive systems tract, and Subunit 1D is interpreted as a highstand systems tract. The lowstand systems tract deposits consist of overlapping and seaward-prograding shelf-edge wedges deposited during the lowstand and the subsequent initial rise of sea level. These shelf-edge wedges are best developed along the westernmost and easternmost segments of the study area, off the mouths of rivers. The transgressive systems tract deposits consist of a set of shingled, shore-parallel, back-stepping parasequences, deposited during a phase of relatively rapid sea-level rise, and include a number of prograded sediment bodies (including barrier islands, beach deposits) and thin veneers of seismically transparent muds showing onlap onto the flanks of older sedimentary features. A number of radiocarbon dates from gravity cores show that the sedimentary architecture of Unit 1 contain a detailed sedimentary record for the post-glacial sea-level rise along the southwestern Black Sea shelf. These data do not support the catastrophic refilling of the Black Sea by waters from the Mediterranean Sea at 7.1 ka postulated by [Ryan, Pitman, Major, Shimkus, Maskalenko, Jones, Dimitrov, Gorur, Sakinc, Yuce, Mar. Geol. 138 (1997) 119-126], [Ryan, Pitman, Touchstone Book (1999) 319 pp.], and [Ballard, Coleman, Rosenberg, Mar. Geol. 170 (2000) 253-261]

Blow Hole Cave: An unroofed cave on San Salvador Island, the Bahamas, and its importance for detection of paleokarst caves on fossil carbonate platforms, 2002,
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Bosá, K Pavel, Mylroie John E. , Hladil Jindrich, Carew James L. , Slaví, K Ladislav

The comparative study of a Quaternary carbonate platform (San Salvador Island, the Bahamas) and a Devonian Carbonate Platform (Krásná Elevation, Moravia) indicates a great similarity in karst evolution. Caves on both sites are interpreted as flank margin caves associated with a freshwater lens and halocline stabilised during sea-level highstands. The sedimentary fill of both caves is genetically comparable - beach and aeolian sediments with bodies of breccias.


Cyclic sequences, events and evolution of the Sino-Korean plate, with a discussion on the evolution of molar-tooth carbonates, phosphorites and source rocks, 2003,
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Meng X. H. , Ge M. ,
This paper gives an account of the research that the authors conducted on the cyclic sequences, events and evolutionary history from Proterozoic to Meso-Cenozoic in the Sino-Korean plate based on the principle of the Cosmos-Earth System. The authors divided this plate into 20 super-cyclic or super-mega-cyclic periods and more than 100 Oort periods. The research focused on important sea flooding events, uplift interruption events, tilting movement events, molar-tooth carbonate events, thermal events, polarity reversal events, karst events, volcanic explosion events and storm events, as well as types of resource areas and paleotectonic evolution. By means of the isochronous theory of the Cosmos-Earth System periodicity and based on long-excentricity and periodicity, the authors elaborately studied the paleogeographic evolution of the aulacogen of the Sino-Korean plate, the oolitic beach platform formation, the development of foreland basin and continental rift valley basin, and reconstructed the evolution of tectonic paleogeography and stratigraphic framework in the Sino-Korean plate in terms of evolutionary maps. Finally; the authors gave a profound discussion on the formation and development of molar-tooth carbonates, phosphorites and source rocks

Quaternary calcarenite stratigraphy on Lord Howe Island, southwestern Pacific Ocean and the record of coastal carbonate deposition, 2003,
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Brooke Bp, Woodroffe Cd, Murraywallace Cv, Heijnis H, Jones Bg,
Lord Howe Island is a small, mid-ocean volcanic and carbonate island in the southwestern Pacific Ocean. Skeletal carbonate eolianite and beach calcarenite on the island are divisible into two formations based on lithostratigraphy. The Searles Point Formation comprises eolianite units bounded by clay-rich paleosols. Pore-filling sparite and microsparite are the dominant cements in these eolianite units, and recrystallised grains are common. Outcrops exhibit karst features such as dolines, caves and subaerially exposed relict speleothems. The Neds Beach Formation overlies the Searles Point Formation and consists of dune and beach units bounded by weakly developed fossil soil horizons. These younger deposits are characterised by grain-contact and meniscus cements, with patchy pore-filling micrite and mirosparite. The calcarenite comprises several disparate successions that contain a record of up to 7 discrete phases of deposition. A chronology is constructed based on U/Th ages of speleothems and corals, TL ages of dune and paleosols, AMS 14C and amino acid racemization (AAR) dating of land snails and AAR whole-rock dating of eolianite. These data indicate dune units and paleosols of the Searles Point Formation were emplaced during oxygen isotope stage (OIS) 7 and earlier in the Middle Pleistocene. Beach units of the Neds Beach Formation were deposited during OIS 5e while dune units were deposited during two major phases, the first coeval with or shortly after the beach units, the second later during OIS 5 (e.g. OIS 5a) when the older dune and beach units were buried.Large-scale exposures and morphostratigraphical features indicate much of the carbonate was emplaced as transverse and climbing dunes, with the sediment source located seaward of and several metres below the present shoreline. The lateral extent and thickness of the eolianite deposits contrast markedly with the relatively small modern dunes. These features indicate that a slight fall (2-10 m) in sea level may be required to mobilise relatively large volumes of sediment onto the island. The stratigraphy of the calcarenite, combined with the shallow depth of the platform surrounding the island (30-50 m present water depth) and the geochronological data, suggest that cycles of carbonate deposition on the island are linked to interglacial and interstadial periods of high or falling sea level

Sedimentation and porosity enhancement in a breached flank margin cave, 2004,
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Florea Lj, Mylroie Je, Price A,
San Salvador Island, Bahamas, provides unique opportunities to study modem geologic processes on carbonate platforms as a result of constraints in time and space. The time span of exposed geology is limited to the middle Pleistocene through Holocene (< 500 ka), and the island lies on an isolated platform (12 by 19 km). Altar Cave, formed within an oxygen isotope substage 5e eolianite (approximately 125 ka) of the Grotto Beach Formation on San Salvador, is a classic example of a flank margin cave that has been exposed during hillslope retreat. The nature of Altar Cave (restricted entrance, simplistic morphology, and easy access) facilitates a sedimentation study. Sediment profiles from trenches dug at three locations in Altar Cave show that the deposits in the cave formed as an early stage of development of a Holocene strand plain that is present today between the cave and the beach. Altar Cave was breached by Holocene coastal processes; C-14 dates show sand fill deposits in the cave to be Holocene (4.7 ka). C-14 dates, XRD, and geochemical analyses show the surficial sediment to be recent (0.6 ka), and that leaching has altered the bedrock floor of the cave. Petrologic study of the floor rock has provided evidence of autogenic sedimentation prior to breaching of the cave in the form of dissolution residuum accumulating during, cave development. Petrologic analysis shows that this leaching has resulted in increased bedrock porosity below the sediment profile. Also, introduced organics have contaminated the late Pleistocene bedrock with young carbon, resulting in C-14 ages of 14 ka at 0.3 m in depth and 28 ka at 1.3 m in depth. The results of this study demonstrate a potential method of porosity enhancement in young carbonates by vadose leaching. Porosity-enhanced zones have implications for our understanding of recharge to fresh-water lenses on carbonate islands

Coastal cliff geohazards in weak rock: the UK Chalk cliffs of Sussex, 2004,
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Mortimore R. N. , Lawrence J. , Pope D. , Duperret A. , Genter A. ,
Geohazards related to chalk coastal cliffs from Eastbourne to Brighton, Sussex are described. An eight-fold hazard classification is introduced that recognizes the influence of chalk lithology, overlying sediments and weathering processes on location, magnitude and frequency of cliff collapses. Parts of the coast are characterized by cliffs of predominantly a single chalk formation (e.g. Seven Sisters) and other sections are more complex containing several Chalk formations (Beachy Head). Rock properties (intact dry density or porosity) and mass structure vary with each formation and control cliff failure mechanisms and scales of failures. The Holywell Nodular Chalk, New Pit Chalk and Newhaven Chalk formations are characterized by steeply inclined conjugate sets of joints which lead to predominantly plane and wedge failures. However, the dihedral angle of the shears, the fracture roughness and fill is different in each of these formations leading to different rock mass shear strengths. In contrast the Seaford and Culver Chalk formations are characterized by low-density chalks with predominantly clean, vertical joint sets, more closely spaced than in the other formations. Cliff failure types range from simple joint controlled conventional plane and wedge failures to complex cliff collapses and major rock falls (partial flow-slides) involving material failure as well as interaction with discontinuities. Other hazards, related to sediments capping the Chalk cliffs, include mud-slides and sandstone collapses at Newhaven, and progressive failure of Quaternary Head and other valley-fill deposits. Weathering, including the concentration of groundwater flow down dissolution pipes and primary discontinuities, is a major factor on rate and location of cliff collapses. A particular feature of the Chalk cliffs is the influence of folding on cliff stability, especially at Beachy Head, Seaford Head and Newhaven. A new classification for cliff collapses and a new scale of magnitude for collapses are introduced and used to identify, semi-quantify and map the different hazards. Climate (and climate change) and marine erosion affect the rate of development of cliff collapse and cliff-line retreat. This was particularly evident during the wet winters of 1999-2000-2001 when the first major collapses along protected sections of coastline occurred (Peacehaven Cliffs protected by an undercliff wall; Black Rock Marina the Chalk cliffs and the Quaternary Head). It is the geology, however, that controls the location and scale of erosion and cliff failure

Contrle structural et tectonique sur lhydrogologie karstique du plateau Mahafaly (domaine littoral semi-aride, sud-ouest de Madagascar), 2005,
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Andr Grgoire, Bergeron Gilles, Guyot Luc
Structural and tectonic control on karstic hydrogeology of the plateau Mahafaly (semiarid coastal area, South-West of Madagascar) - The southwestern coast of Madagascar is characterized by a semiarid climate and low fresh water resources, which slow down the economic development. The studied area, located south of Toliara, is separated into a western coast of aeolian dunes and sandstones, where most of the people live, and the eastern, almost unoccupied, calcareous Mahafaly plateau. The coastal aquifer is dominated by salty water. The conductivity, close to 6000S/cm in the north, decreases to 3000S/cm in the south. The coastal plain is bordered to the East by highly karstified Cenozoic limestone, separated by a north-south cliff corresponding to the Toliara fault scarp. Surveys in coastal wells and in karstic aquifers clearly point out tidal influence on piezometric level and conductivity. In the north, the limestone cliff is directly in contact with the sea, whose water contaminates the karstic aquifer according to tidal variations. In the south, fresh water flows out on the beach by resurgences in the Quaternary sandstones, probably connected to the Eocene limestones, 5 km to the east. Drillings and exploration of some shafts on the plateau permitted access to the ground water table. It displays various conductivities ranging between 1500S/cm and 5000S/cm, unusually high for a karstic aquifer far away from the coast. The mapping of such conductivities suggests more complex phenomena than only marine intrusions into the different aquifer systems. Chemical and isotopic analyses show an obvious seawater intrusion and evaporation influence for the coastal aquifer. Iin the karstic aquifer, however, trace element analyses evoke contamination by upwelling of deep mineralized water. Salty water is frequent eastward on the basement and in the Mesozic formations. Today, fracture zones in both the coastal sandstones and in the Cenozoic limestone units control ground water circulations. Such fractures result from extensional phases in the past. The surface joint directions N-S, NE-SW and NW-SE reflect the deep-seated horst and graben structures. Microtectonic analyses give evidence of a post-Eocene WNW-ESE extension, and recent seismic data define an E-W extensional regime. The underground flowpaths are mostly on fractures oriented along the present stress field. The tectonic history in the area and the chemical composition of the waters suggest a connection of the karst aquifer with circulations from deep formations through deep-seated faults belonging to the Toliara fault system. This could explain abnormal salinities in the karstic system, far away from the coast.

Rock coast morphology in relation to lithology and wave exposure, Lord Howe Island, southwest Pacific, 2005,
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Dickson Me, Woodroffe Cd,
The morphology of rock coastlines appears primarily to be a function of the eroding force of waves and the resistance of rocks, but a number of local factors complicate determination of the relative significance of these as opposed to other factors. Lord Howe Island, a small, basaltic mid-oceanic island in the northern Tasman Sea, presents a unique opportunity to differentiate the roles of rock resistance and wave exposure. The island occurs at the southern limit of coral growth and there is a fringing coral reef and lagoon on a portion of the western coastline. The reef markedly attenuates wave energy and there is an impressive contrast between the sheltered lagoonal coastline, which consists largely of depositional sandy beaches and vegetated hillslopes, and the exposed coastline which is bold and rugged having been eroded by waves into precipitous plunging cliffs, cliffs with talus slopes, and cliffs with basal shore platforms. There is a clear contrast between the development of basalt shore platforms along the sheltered and exposed coastlines: exposed platforms are wider, backed by a higher and steeper cliff, and are without talus deposits, as opposed to sheltered platforms that are veneered by talus. Calcarenites, deposited in the Late Pleistocene, hence precluding significant rock coast inheritance, have been eroded into platforms that are approximately twice as wide on the exposed coastline than the sheltered coastline. Further evidence as to the efficacy of wave erosion around Lord Howe Island is provided by a suite of landforms that appear to have developed as a result of localised wave-quarrying of highly jointed dykes (sea caves, arches, blowholes, and gulches)

Coastal karst geomorphosites at risk? A case study: the floods of 6-11 December 2004 in central-east Sardinia, 2007,
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Cossu A, De Waele J, Di Gregorio F,
Extreme rainfall causing floods and great damage occurred in many areas of central-east Sardinia in the period 6-11 December 2004. A total of approximately 700 mm of rain was measured during this extreme event, with a maximum reaching 510 mm of rainfall in 1 day at the rain gauge of Villagrande (Ogliastra). During and immediately after the event all fluviokarstic canyons were activated for at least 1 week, reaching the highest water levels in at least 50 years and reversing great quantities of sediment-loaded water onto the coast and with important geomorphical modifications. There was public fear that serious damage to the natural resources would occur, such as the famous Cala Luna beach that was almost completely destroyed by the flooding of the Codula Ilune River and by the coinciding sea storm. The river, in fact, eroded the longshore bar (beach) and destroyed the small backshore lagoon. A monitoring study has been initiated in order to analyse the natural evolution of this littoral system and to define the resilience of this interesting geomorphosite. The observations have shown that the flood, albeit impacting negatively in the moments immediately after the disaster, almost completely restored the natural equilibrium of this coastal karst geo-ecosystem within a season

Fresh-water lens anisotropy and flank margin cave development, Fais Island, FSM, 2011,
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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.


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