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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. ...

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. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
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 Rundkarren is (german.) 1. karren forms with rounded edges; formed by soil water than cannot flow freely due to the tightness of soil pores and thus corrodes away all edges and points. the small karren forms disappear, grooves and grikes are widened and deepened. one or two centuries after being laid bare, the earlier rounded edge is only just recognizable so round karren and their remains provide evidence of an earlier soil covering [3]. 2. karren form comprising rounded channels, commonly 50-500mm deep and wide and separated by rounded ridges. rundkarren are the characteristic dissolutional form created beneath superficial material such as sandy till, peat or other soil, or beneath a cover of plants or lichen [9]. synonym: round karren. see also karren.?

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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
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Your search for beaches (Keyword) returned 17 results for the whole karstbase:
Showing 1 to 15 of 17
Observations on the aquatic subterranean fauna of Cuba., 1973, Botosaneanu Lazare
A short account on some achievements of the cubano-romanian biospeleological expeditions to Cuba in the study of the aquatic subterranean faunas. The following divisions of the aquatic subterranean realm are reviewed together with their most characteristic faunal elements: "guano pools" and rimstone pools in the vadose zone of the caves; underground streams; water table (and other) lakes in the caves; "pozzos" carved in the limestone, and "grietas" which are vertical clefts in the limestone of marine terraces, giving access to fresh- or to brackish water; the interstitial of the marine beaches; the underflow of running waters. At present, thorough biospeleological research is being carried out almost everywhere in Central America; Cuba, which remained until recently rather poorly investigated, proves to be one of the most remarkable areas from this point of view. A few of the most interesting problems rose in the course of the study of the underground aquatic fauna of Cuba are listed. An interesting biogeographical problem is the following: some of the subterranean aquatic elements prove to be related to elements belonging to the fauna of the other Antilles and of Mexico, but not to the South-American fauna (as is the case for some terrestrial groups). The research undertaken will be a contribution to the problem of the divisions of the aquatic subterranean realm and of their reciprocal relations, in a warm and humid climate; it will also contribute an answer to the problem of the differences between temperate and tropical cave communities; finally, it allows one to perceive in its very progress the process of colonization of the subterranean freshwaters by elements of marine origin, either through the interstitial realm or through the fissures of the littoral limestones.

Observations on the aquatic subterranean fauna of Cuba., 1973, Botosaneanu Lazare
A short account on some achievements of the cubano-romanian biospeleological expeditions to Cuba in the study of the aquatic subterranean faunas. The following divisions of the aquatic subterranean realm are reviewed together with their most characteristic faunal elements: "guano pools" and rimstone pools in the vadose zone of the caves; underground streams; water table (and other) lakes in the caves; "pozzos" carved in the limestone, and "grietas" which are vertical clefts in the limestone of marine terraces, giving access to fresh- or to brackish water; the interstitial of the marine beaches; the underflow of running waters. At present, thorough biospeleological research is being carried out almost everywhere in Central America; Cuba, which remained until recently rather poorly investigated, proves to be one of the most remarkable areas from this point of view. A few of the most interesting problems rose in the course of the study of the underground aquatic fauna of Cuba are listed. An interesting biogeographical problem is the following: some of the subterranean aquatic elements prove to be related to elements belonging to the fauna of the other Antilles and of Mexico, but not to the South-American fauna (as is the case for some terrestrial groups). The research undertaken will be a contribution to the problem of the divisions of the aquatic subterranean realm and of their reciprocal relations, in a warm and humid climate; it will also contribute an answer to the problem of the differences between temperate and tropical cave communities; finally, it allows one to perceive in its very progress the process of colonization of the subterranean freshwaters by elements of marine origin, either through the interstitial realm or through the fissures of the littoral limestones.

A new species of Sipuncula (Aspidosiphon exiguus n.sp.), belonging to the interstitial fauna of marine beaches collected by Mr. L. Botosaneanu during the second Cuban-Romanian biospeleological expedition to Cuba 1973., 1974, Edmonds S. J.
Aspidosiphon exiguous, a new species of Sipuncula, is decribed, belonging to the interstitial fauna of the beaches. The specimens were collected during the second Cuba-Romanian biospeleological expedition in 1973.

Origin of the epeirogenic uplift of Pliocene-Pleistocene beach ridges in Florida and development of the Florida karst, 1984, Opdyke Neil D. , Spangler D. P. , Smith D. L. , Jones D. S. , Lindquist R. C. ,
Marine fossils of Pleistocene age are known to occur in beach ridges near the border of northern Florida and southern Georgia at elevations of between 42 and 49 m above mean sea level. No evidence exists for a massive melt-off of glacial ice, which would be required to raise sea level to these elevations. Florida, therefore, must have been uplifted epeirogenically during the Pleistocene. Measurement of dissolved solids in Florida's springs demonstrates that the karst area is losing a minimum of 1.2 X 10 6 m 3 /yr of limestone through spring flow, the equivalent of 1 m of surficial limestone every 38,000 yr. This loss has led to an isostatic uplift of the north-central part of the Florida peninsula of at least 36 m during the Pleistocene and Holocene, which agrees with observed elevations of marine terraces.--Modified journal abstract

Barbuda--an emerging reef and lagoon complex on the edge of the Lesser Antilles island are, 1985, Brasier M, Donahue J,
The Pliocene to Holocene limestones of Barbuda have formed on a wide, shallow, outlying bank of the Lesser Antilles island arc, some 50 km east of the older axis of the Limestone Caribbees and 100 km east of the newer axis of the active Volcanic Caribbees. Contrasts with neighbouring islands of similar size include the lack of exposed igneous basement or mid-Tertiary sediments, the dominance of younger flat-lying carbonates, and the greater frequency of earthquake shocks. The history of emergence of the island has been studied through aerial reconnaissance, mapping, logging, hand coring, facies and microfacies analysis. These show a pattern of progressively falling high sea level stands (from more than 50 m down to the present level) on which are superimposed at least three major phases of subaerial exposure, when sea levels were close to, or below, their present level. This sequence can be summarized as follows: 1, bank edge facies (early Pliocene Highlands Formation) deposited at not more than c. 50-100 m above the present sea level; 2, emergence with moderate upwarping in the north, associated with the Bat Hole subaerial phase forming widespread karst; 3, older Pleistocene transgression with fringing reefs and protected bays formed at l0 to l5 m high sea level stands (Beazer Formation); 4, Marl Pits subaerial phase with widespread karst and soil formation; 5, late Pleistocene transgression up to m high stand with fringing and barrier reefs, protected backreefs and bays (Codrington Formation Phase I); 6, gradual regression resulting in emergence of reefs, enclosure of lagoons, and progradation of beach ridges at heights falling from c. 5 m to below present sea level (Codrington Phase II); 7, Castle Bay subaerial phase produced karst, caliche and coastal dunes that built eastwards to below present sea level; and 8, Holocene transgression producing the present mosaic, with reefs, lagoons and prograding beach ridge complexes, with the present sea level reached before c. 4085 years BP. The evidence suggests that slight uplift took place in the north of the island after early Pliocene times. Subsequent shoreline fluctuations are consistent with glacio-eustatic changes in sea level, indicating that the island has not experienced significant uplift during the Quaternary

SMALL-SCALE RETROSPECTIVE GROUND-WATER MONITORING STUDY FOR SIMAZINE IN DIFFERENT HYDROGEOLOGICAL SETTINGS, 1991, Roux P. H. , Hall R. L. , Ross R. H. ,
A ground water monitoring study was conducted for the triazine herbicide simazine at 11 sites in the United States. The study used carefully selected, small-scale sites (average size: about 33 acres) with documented product use and sensitive hydrogeological settings. The sites selected were Tulare County, California (two sites); Fresno County, California; Sussex County, Delaware; Hardee and Palm Beach counties, Florida; Winnebago County, Illinois; Jackson County, Indiana; Van Buren and Berrien counties, Michigan; and Jefferson County, West Virginia. These sites satisfied the following criteria: a history of simazine use, including the year prior to the start of the study; permeable soil and vadose zone; shallow depth to water; no restrictive soil layers above the water table; and gentle slopes not exceeding 2 percent. A variety of crop types, climates, and irrigation practices were included. Monitoring well clusters (shallow and deep) were installed at each site except in California and West Virginia, where only shallow wells were installed. Simazine was monitored at these sites at quarterly intervals for a two-year period during 1986-1988. The results of the study showed that out of 153 samples analyzed, 45 samples showed simazine detections. A substantial majority of the detections (32 out of 45) occurred in Tulare, Fresno, and Jefferson counties. The detections in these areas were attributed to mechanisms other than leaching, such as drainage wells, karst areas, surface water recharge, or point source problems. An additional 11 detections in Van Buren County were apparently due to an unknown upgradient source. Only one detection (in Palm Beach County, Florida) near the screening level of 0.1 ppb was attributed to possible leaching. The results of this investigation support the hypothesis that simazine does not leach significantly under field use conditions

HOLOCENE MARINE CEMENT COATINGS ON BEACH-ROCKS OF THE ABU-DHABI COASTLINE (UAE) - ANALOGS FOR CEMENT FABRICS IN ANCIENT LIMESTONES, 1994, Kendall C. G. S. , Sadd J. L. , Alsharhan A. ,
Marine carbonate cements, which are superficially like travertines from meteoric caves, are coating and binding some intertidal sedimentary rock surfaces occurring in coastal Abu Dhabi, the United Arab Emirates, (UAE). Near Jebel Dhana these surficial cements can be up to 3 cm thick and envelope beach rock surfaces and fossils. They are also present both as thin coats and a fracture-fill cement in the intertidal hard grounds associated with the Khor Al Bazam algal flats. The thickness, microscopic characteristics, and morphology of the marine cement coatings from Jebel Dhana indicates incremental deposition of aragonite in conjunction with traces of sulfate minerals. Most of these cement coatings are micritic, but the layers which encrust the hard grounds from the algae flat of the Khor al Bazam have a more radial and fibrous micro-structure and are composed solely of aragonite. The stable isotopic composition of coatings from Jebel Dhana (delta(18)O = .35, delta(13)C = .00) falls within the compositional range for modem marine non skeletal aragonite and suggests that the marine travertine-like cements precipitate from the agitated slightly hypersaline Arabian Gulf sea water during repeated cycles of exposure, evaporation and immersion. Similar cement coatings and microfabrics are present in the tepee structured and brecciated sediments of the Guadalupe Mountains (Permian) and the Italian Alps (Triassic), in Holocene algal head cements from the Great Salt Lace, and in similar Tertiary algal heads in the Green River Formation of the western US. The petrographic similarity of these ancient ''flow stone'' like cements with Recent hypersaline marine cement coatings suggests that high rates of carbonate cementation and hypersaline conditions contribute to tepee formation and cavity fill

GEOLOGY AND KARST GEOMORPHOLOGY OF SAN-SALVADOR ISLAND, BAHAMAS, 1995, Mylroie J. E. , Carew J. L. ,
The exposed carbonates of the Bahamas consist of late Quaternary limestones that were deposited during glacio-eustatic highstands of sea level. Each highstand event produced transgressive-phase, stillstand-phase, and regressive-phase units. Because of slow platform subsidence, Pleistocene carbonates deposited on highstands prior to the last interglacial (oxygen isotope substage 5e, circa 125,000 years ago) are represented solely by eolianites. The Owl's Hole Formation comprises these eolianites, which are generally fossiliferous pelsparites. The deposits of the last interglacial form the Grotto Beach Formation, and contain a complete sequence of subtidal intertidal and eolian carbonates. These deposits are predominantly oolitic. Holocene deposits are represented by the Rice Bay Formation, which consists of intertidal and eolian pelsparites deposited during the transgressive-phase and stillstand-phase of the current sea-level highstand. The three formations are separated from one another by well-developed terra-rossa paleosols or other erosion surfaces that formed predominantly during intervening sea-level lowstands. The karst landforms of San Salvador consist of karren, depressions, caves, and blue holes. Karren are small-scale dissolutional etchings on exposed and soil-covered bedrock that grade downward into the epikarst, the system of tubes and holes that drain the bedrock surface. Depressions are constructional features, such as swales between eolian ridges, but they have been dissolutionally maintained. Pit caves are vertical voids in the vadose zone that link the epikarst to the water table. Flank margin caves are horizontal voids that formed in the distal margin of a past fresh-water lens; whereas banana holes are horizontal voids that developed at the top of a past fresh-water lens, landward of the lens margin. Lake drains are conduits that connect some flooded depressions to the sea. Blue holes are flooded vertical shafts, of polygenetic origin, that may lead into caves systems at depth. The paleokarst of San Salvador is represented by flank margin caves and banana holes formed in a past fresh-water lens elevated by the last interglacial sea-level highstand, and by epikarst buried under paleosols formed during sea-level lowstands. Both carbonate deposition and its subsequent karstification is controlled by glacio-eustatic sea-level position. On San Salvador, the geographic isolation of the island, its small size, and the rapidity of past sea level changes have placed major constraints on the production of the paleokarst

Geomorphological evidence for anti-Apennine faults in the Umbro-Marchean Apennines and in the peri-Adriatic basin, Italy, 1996, Coltorti M, Farabollini P, Gentili B, Pambianchi G,
The Apennines are a relatively recent mountain chain which has been affected by uplift movements since the Upper Pliocene. In fact the remnants of an “erosional surface”, reduced close to base level, is preserved at the top of the relief. There is no general agreement on the geodynamic stress field and mechanisms which are creating the chain. However, it is largely accepted that uplift occurred together with the activation, on the western side of the chain, of extensive faults, oriented in the Apennine direction (NW-SE), which have been linked to the opening of the Tyrrhenian sea. A great debate is going on about the presence and significance of anti-Apennine faults (NE-SW) which have been observed by some authors but completely denied by others.The main evidence is represented by[ (1) block faulting of the remnants of the “erosional surface”. Along the Marchean Ridge, more elevated relief, delimiting relatively depressed areas, was created in correspondence with the Sibillini Mts. and Mt. S. Vicino. Similar evidence has been found in the Umbro-Marchean Ridge. Locally more than 1500 metres of displacement have been observed between more and less uplifted remnants. (2) Block faulting of fan deltas and related beaches, of Sicilian to Crotonian age, with more elevated sediments preserved between the Tronto and Tenna rivers and between the Musone and Esino rivers. Maximum displacement along a transect parallel to the coast is 200 metres. (3) fault-scarps affecting the Middle Pleistocene river terraces, as observed along the Esino, the Tronto, the Chienti and the Tenna river valleys. Maximum displacements are in the order of 50 metres. (4) Faulting of horizontal karst galleries and reorientation of the cave network, as in the Frasassi Gorge. Maximum displacements are about 100 metres. (5) Captures and alignments in the drainage network of the main river courses. (6) Large-scale gravitational movements, as in the Ancona landslide, and along the Chienti and Esino rivers.Their activation occurred in most cases after the Lower Pleistocene and although their displacements may be of relatively limited extent, dispite their recent activity, they played a major role in the modelling of the landscape. These faults display transtensive, extensional and trascurrent movements. Apart from the controversial geodynamic significance of these faults, from a geomorphological point of view they must be considered transverse elements of the stress field from blocks more or less uplifted along the Apennine chain.The importance and timing of activity of these faults in the Quaternary geomorphological evolution of the Umbria-Marchean Apennines is demonstrated using evidence usually underestimated by structural geologists, which can contribute to a debate based on a multidisciplinary approach

Facies differentiation and sequence stratigraphy in ancient evaporite basins - An example from the basal Zechstein (Upper Permian of Germany), 1999, Steinhoff I. , Strohmenger C. ,
Due to excellent preservation, the Werra Anhydrite (Al), the upper member of the Upper Permian Zechstein cycle I (Ist cycle, Z1), is readily studied in terms of the distribution of sulfate facies and sequence stratigraphy that can be interpreted from these facies. In this study cores taken from seven wells in the Southern Zechstein Basin were examined for their sedimentary structures and various petrographic features. Facies interpretation and depositional sequences are based on detailed examination of core material. Four main facies environments have been identified: (I) supratidal (II) intertidal (III) shallow subtidal, and (IV) deeper (hypersaline) subtidal. These are further subdivided into 10 subfacies types: (1) karst and (2) sabkha within the supratidal environment (I), (3) algal tidal-flat, (4) tidal flat and (5) beach deposit within the intertidal environment (II), (6) salina, and (7) sulfate arenites within the shallow subtidal enviromnent (III). The (8) slope subfacies type commonly associated with (9) turbidites and the (10) basin subfacies type subdivide the deeper subtidal environment (IV). Vertical stacking patterns of these facies and subfacies types reveal the sequence stratigraphic development of the sulfate cycles in response to sea-level and salinity fluctuations. The lower Werra Anhydrite (belonging to Zechstein Sequence ZS2) is characterized by a transgressive systems tract (IST) overlying the transgressive surface of Zechstein Sequence ZS2 within the Al-underlying upper Zechstein Limestone (Cal). The TST of the AT is several tens of meters thick in platform areas, where it is built up by sulfate arenites and swallow-tail anhydrite-after-gypsum, and thins out to a few meters of thickness toward the condensed basinal section, where laminites ('Linien-Anhydrit') are predominant. Most of the Al succession consists of three relatively thick parasequences belonging to the highstand systems tract (HST) that shows typical prograding sets. Enhanced platform Buildup, including sulfate arenites, salina deposits, intertidal sediments, and sabkha precipitation as well as turbidite shedding off the platforms produced marginal ''sulfate walls' up to 400 m thick as platform to slope portions of the Werra Anhydrite. Seaward, the Al thins to a few tens of meters of laminated sulfate basin muds. Increasingly pronounced Al topography during highstand narrowed the slope subfacies belt parallel to the platform margin This contrasts with the broad but considerably thinner slope deposits of transgressive times with much shallower slopes. The ensuing sea-level lowstand is reflected by a sequence boundary on top of the karstified Al-platform and a lowstand wedge (Zechstein Sequence ZS3) overlying portions of the slope and basinal subfacies of the Al highstand systems tract Beyond the lateral limits of the lowstand wedge, the sequence boundary merges with the transgressive surface of ZS3, shown by the lithologic change from the Al anhydrites to the overlying carbonates of the Stassfurt Carbonates ('Haupt Dolomit' Main Dolomite, Ca2). The Basal Anhydrite (A2), which overlies and seals the carbonate reservoir of the Ca2, can also be subdivided into systems tracts by means of facies analysis. It is, however, much less complex than the Al and is comprised almost exclusively of a transgressive systems tract of Zechstein Sequence ZS4

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, 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]

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, 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, 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, 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

Rock coast morphology in relation to lithology and wave exposure, Lord Howe Island, southwest Pacific, 2005, 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)

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