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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 turbidity is a diminishing of light penetration through a water sample due to suspended and colloidal materials.?

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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 sea level change (Keyword) returned 37 results for the whole karstbase:
Showing 16 to 30 of 37
Evolution of river network at the 'Cevennes-Grands Causses' transition: Consequences for the evaluation of uplift, 2001, Camus H,
The Mediterranean catchment of the Cevennes (S. France) presents deep incision of the river network (fig. 1 and 2). Combined geomorphology and analyses of the residual sedimentary formations allows to reconstruct a complex history of river network evolution, including capture of tributaries of the Herault River (fig. 1, 2 and 3). The history of uplift of the upstream drainage area could be estimated from the provenance studies of the fluvial and karstic deposits, however river incision is also controlled sea-level changes and differential erosion, which makes reconstruction more complex. Allochthonous clasts types Analyses of allochtonous deposits on the Grands Causses surface reveals different origin for sediments from the hill top and the Airoles valley (fig. 4b), which was previously unrecognised. Facies 1 is found on the highest points of the Grands Causses surface (well sorted rounded quartz pebbles in red shale matrix) it corresponds to a weathered residual sediments (dismantling of an ancient cover). Facies 2 is found on the slope of the Airoles Valley (fig. 7). It consists of alluvial crystalline poorly sorted clasts with outsized clasts (up to 50cm) of quartz-vein, schists in a matrix of shales and sand (weathered granite). Between the hill tops and the Airoles Valley, karstic network presents a sediment fill with clasts reworked from facies I and facies 2 (fig. 6). Airoles valley model : an example of diachronic formation of drainage network The Airoles dry valley stretches on the Grands Causses from the north (700 m) to the south into the present thalweg line of the Vis canyon (500 m) (fig. 1b & 3). Crystalline deposits witness an ancient catchment in the Cevennes. Presently, the catchment in the crystalline basement is disconnected and captured by the Arre River flowing eastwards (fig. 3 & 4a). The profile of the Airoles abandoned valley connects with the present Vis Canyon, therefore, at the time of capture, incision of the Vis canyon had reached its present altitude (fig. 4a). The geomorphologic evolution of this area took place in three stages (fig. 8). 1) The Grands Causses acted as piedmont for the crystalline highlands of the Massif Central (fig. 8A). A latter karstic evolution (tropical climate) allowed the weathered residual sediments (facies 1) (fig. 8A). 2) Incision of the Vis karstic canyon implies that the Herault incision and terraces (facies 2) (fig, 8B) of the Airoles valley occurred during this stage. 3) The Arre valley head propagates westward by regressive erosion and finaly captured the Airoles river crystalline catchment (fig. 8C). Consequence for the Cevennes uplift and hydrographic network development Although the values of present vertical incision in the Vis canyon and in the Arre valley are similar, but they achieved at different time. In addition, the narrow and deep canyon of the Vis is due to vertical incision from the karstic surface of the Grands Causses, whereas the Arre wide valley results from (a younger) lateral slops retreat from a low Herault base-level. The Vis karstic canyon developed in a similar way to the major karstic canyons of both Mediterranean and Atlantic catchment (i.e. Tarn). This rules out a Messinian Mediterranean desiccation as incision driving mechanism and suggests tectonic uplift of the Cevennes and surrounding areas. The Tam being already incised by 13 My [Ambert, 1990], it implies a Miocene age for the incision. Conclusion The amplitude of the vertical incision cannot therefore be used in a simple way to interpret the uplift history of the basement. Consequently, geomorphologic analysis appears to be a prerequisite to distinguish the part played by each factor, and to select the site of uplift measurement

Sea level change through the last glacial cycle., 2001, Lambeck K. , Chappell J.

Late Archaean foreland basin deposits, Belingwe greenstone belt, Zimbabwe, 2001, Hofmann A. , Dirks P. H. G. M. , Jelsma H. A. ,
The c. 2.65 Ga old sedimentary Cheshire Formation of the Belingwe greenstone belt (BDB), central Zimbabwe, has been studied in detail for the first time to shed some light on the much debated evolution of this classical belt. The Cheshire Formation rests sharply on a mafic volcanic unit (Zeederbergs Formation) and comprises a basal, eastward-sloping carbonate ramp sequence built of shallowing-upward, metre-scale sedimentary cycles. The cycles strongly resemble Proterozoic and Phanerozoic carbonate cycles and might have formed by small-scale eustatic sea level changes. The top of the carbonate ramp is represented by a karst surface. The carbonates are overlain by and grade laterally to the east into deeper water (sub-wave base) siliciclastic facies. Conglomerate, shale and minor sandstone were deposited by high- to low-density turbidity currents and were derived from the erosion of Zeederbergs-like volcanic rocks from the east. Shortly after deposition, the Cheshire Formation and underlying volcanics were affected by a northwest-directed thrusting event. Thrusting gave rise to the deformation of semi-consolidated sediments and resulted in the juxtaposition of a thrust slice of Zeederbergs basalts onto Cheshire sediments. The stratigraphy, asymmetric facies and sediment thickness distribution, palaeogeographic constraints and evidence for an early horizontal tectonic event suggest that the Cheshire Formation formed in a foreland-type sedimentary basin. (C) 2001 Elsevier Science B.V. All rights reserved

The Carbonate Island Karst Model applied to Guam., 2001, Mylroie J. , Jenson J.
The karst of tropical carbonate islands is unique because: 1) fresh water-salt water mixing occurs at the base and margin of the fresh-water lens; 2) glacioeustasy has moved the freshwater lens up The karst of tropical carbonate islands is unique because: 1) fresh water-salt water mixing occurs at the base and margin of the fresh-water lens; 2) glacioeustasy has moved the freshwater lens up and down through a vertical range of over 100m; and 3) the karst is eogenetic, i.e., it has developed in young carbonate rocks that have never been buried beyond the range of meteoric diagenesis. Carbonate islands can be divided into three categories based on basement-sea level relationships: simple carbonate islands (no non-carbonate rocks), carbonate cover islands (non-carbonate rocks beneath a carbonate veneer), and composite islands (carbonate and non-carbonate rocks exposed on the surface). These ideas form the Carbonate Island Karst Model (CIKM) which can be visualized in terms of a three-dimensional framework, with island size on the x-axis, sea-level change on the y-axis, and bedrock relationships on the z-axis. On Guam, tectonic uplift and glacio-eustatic sea level change have produced a complex history on this composite island. The aquifer is partitioned in the subsurface by the .intecedent topography of the volcanic core of the island, and lens discharge is both diffuse and conduit controlled.

Sub-sea level speleothems from the Andaman coast of southern Thailand, and sea level change in Southeast Asia, 2003, Smart Dean

Paleokarst: cessation and rebirth?, 2003, Osborne, R. A. L.

The transformation of active karst into paleokarst by burial, isolation or cessation of process is not necessarily permanent. Paleokarst structures and landforms can be and are exhumed or reactivated, sometimes on numerous occasions. There is not a great deal of similarity between the localities where exhumation and reactivation of paleokarst has been reported. Exhumation and reactivation however have not been reported in many karsts that are similar to those where they have been reported. Exhumation and reactivation appears to be favoured in four situations: - the margins of sedimentary basins overlying grand unconformities, the axes of anticlines, narrow steeply-dipping impounded karsts and where paleokarst fill contains unstable minerals. Six processes are principally responsible for exhumation and reactivation: - per-ascensum speleogenesis, eustatic sea level changes, paragenesis, high density speleogenesis, glaciation, and large-scale meteoric speleogenesis. On some occasions karst landforms, particularly caves or segments of caves, may survive intact and unfilled for geologically significant periods of time. These may be completely isolated from the surface environment, or become reactivated by entrance formation due to breakdown, surface lowering or headward erosion. The intersection and reactivation of ancient open cavities and of exhumed cavities by “modern” caves may be much more common than is currently recognised. If caves have histories as long and as complex as the karsts in which they are developed then many “modern” caves will be composite features composed of interconnected “modern”, relict and exhumed cavities excavated at different times by different processes. Unravelling these histories is the new challenge facing cave science. It will require caves to be studied in a much more detailed, thorough and systematic manner and will also require the application of new technologies in surveying, analysis and dating

The Barremian-Aptian Evolution of The Eastern Arabian Carbonate Platform Margin (Northern Oman), 2003, Hillgartner Heiko, Van Buchem Frans S. P. , Gaumet Fabrice, Razin Philippe, Pittet Bernard, Grotsch Jurgen, Droste Henk,
Carbonate platform margins are sensitive recorders of changes in sea level and climate and can reveal the relative importance of global and regional controls on platform evolution. This paper focuses on the Barremian to Aptian interval (mid Cretaceous), which is known for climatic and environmental changes towards more intensified greenhouse conditions. The study area in the northern Oman mountains offers one of the very few locations where the Cretaceous carbonate margin of the Arabian Plate can be studied along continuous outcrops. Our detailed sedimentological and sequence stratigraphic model of the platform margin demonstrates how major environmental and ecological changes controlled the stratigraphic architecture. The Early Cretaceous platform margin shows high rates of progradation in Berriasian to Hauterivian times followed by lower rates and some aggradation in the Late Hauterivian to Barremian. High-energy bioclastic and oolitic sands were the dominant deposits at the margin. Turbidites were deposited at the slope and in the basin. The Early Aptian platform margin shows a marked change to purely aggradational geometries and a welldeveloped platform barrier that was formed mainly by microbial buildups. The sudden dominance in microbial activity led to cementation and stabilization of the margin and slope and, therefore, a decrease of downslope sediment transport by turbidites. In the Late Aptian, large parts of the Arabian craton were subaerially exposed and a fringing carbonate platform formed. Seven Barremian to Early Albian large-scale depositional sequences reflecting relative sea-level changes are identified on the basis of time lines constrained by physical correlation and biostratigraphy. The reconstruction of the margin geometries suggests that tectonic activity played an important role in the Early Aptian. This was most likely related to global plate reorganization that was accompanied by increased volcanic activity in many parts of the world. Along the northeastern Arabian platform the associated global changes in atmospheric and oceanic circulation are recorded with a change in platform-margin ecology from an ooid-bioclast dominated to a microbial dominated margin. Time-equivalent argillaceous deposits suggest an increase in rainfall and elevated input of nutrients onto the platform. This process contributed to the strongly diminished carbonate production by other organisms and favored microbial activity. The platform margin may thus represent a shallow-marine response to the Early Aptian global changes, commonly associated with an oceanic anoxic event in basinal environments

Post-Miocene stratigraphy and depositional environments of valley-fill sequences at the mouth of Tampa Bay, Florida, 2003, Ferguson Tw, Davis Ra,
Post-Miocene sea-level low stands allowed rivers and karst processes to incise the exposed carbonate platform along the Gulf Coast of Florida. Few Miocene to mid-Pleistocene deposits survived erosion along the present coast except within incised valleys. Since their formation, these valleys have been filled and incised multiple times in response to sea-level changes. The thick sedimentary sequences underlying the mouth of Tampa Bay have been recorded as a range of depositional environments and multiple sea-level incursions and excursions during pre-Holocene time and subsequent to the accumulation of the Miocene carbonate sequences. Sediment analysis of cores collected from a north-south transect across the mouth of Tampa Bay has enabled the identification of lithofacies, ranging from well-sorted, quartz sand to dense, fossiliferous, phosphatic grainstone. These facies were deposited in freshwater, estuarine, and shallow, open marine environments. As a result of channel development and migration within the paleovalley, and cut-and-fill associated with individual transgressions and regressions, correlation of the lithofacies does not extend across the entire transect. Fining-upward sequences truncated by tidal ravinement surfaces that extend throughout the paleovalley can, however, be identified. Age determinations based on 14-C analysis, amino-acid racemization, and strontium isotope analysis dating of numerous samples yield ages of Miocene, Pliocene, early Pleistocene, and late Pleistocene, as well as Holocene for sequences that accumulated and were preserved in this valley-fill complex. Numerous inconsistencies in the stratigraphic organization of the age determinations indicate that there are bad dates, considerable reworking of shells that were dated, or both. For this reason as well as the lack of detailed correlation among the three relatively complete cores, it is not possible to place these strata in a sequence stratigraphic framework. (C) 2003 Elsevier B.V. All rights reserved

Lateglacial and Holocene sea level changes in semi-enclosed seas of North Eurasia: examples from the contrasting Black and White Seas, 2004, Kaplin Pavel A. , Selivanov Andrei O. ,
A comparison of the Black and White Seas, which differ in their tectonic, glacial and climatic history but which share a strong dependence upon limited water exchange with the world ocean, represents an opportunity for the identification of major factors controlling sea level changes during the Lateglacial and Holocene and for the correlation of these changes. Existing data were critically analyzed and compared with the results of geological, geomorphological and palaeohydrological studies obtained by the present authors during the past two decades.We conclude that glacioeustatic processes played a major role in relative sea level changes on most coasts of both areas. However, along several coastlines, other factors overwhelm glacioeustasy during some time intervals. In the Black Sea, water level rose from its minimum position, -100-120 m, at 18-17 ka BP, to -20-30 m at nearly 9 ka BP. In the White Sea, the decreasing trend in relative sea level is well illustrated on the Kola Peninsula and in Karelia, subject to glacioisostatic emergence. A drastic sea level fall from to -25 m occurred with the drainage of glacial lakes in the eastern White Sea (12.5-9.5 ka BP).The Black and White Sea histories changed drastically in the early Holocene or in the beginning of the middle Holocene (9.5-7.5 ka BP) due to the intrusion of water from the Mediterranean and the Barents seas, respectively. During this period, the White Sea developed under the strong influence of the formation of 'ice shelves' and 'dead ice' blocks, retreating glaciers, as well as of glacioisostatic and related processes. The Black Sea history, however, was determined by water exchange with the Mediterranean via the shallow Dardanelles and Bosporus straits (outflow from the Black Sea 10-9.5 ka BP and inflow from 9-7.5 ka BP according to various data), and, partially, by river discharge variations caused by climatic changes on the Russian Plain. The hypothesis of a catastrophic sea level rise from -120-150 to -15-20 m nearly 7550 calendar years BP is not supported by our data. Water intrusion from the Mediterranean was fast but not catastrophic.In the Black Sea, periods of high sea levels after the intrusion of Mediterranean waters are dated from four sedimentary complexes, Vityazevian, Kalamitian, Dzhemetian and Nymphaean, from nearly 7.5, 7-6, 5.5-4.5 and 2.2-1.7 ka BP, respectively. A fluctuating pattern of sea level change was established in the White Sea after the drainage of proglacial lakes and intrusion of ocean waters at the end of the early Holocene (nearly 8.5-8.2 ka BP). Major periods of sea level rise in the White Sea are dated from the late Boreal-early Atlantic (8.5-7.5 ka BP), late Atlantic (6.5-5.2 ka BP), middle Subboreal (4.5-4 ka BP) and middle Subatlantic (1.8-1.5 ka BP). Fluctuations of relative sea level during the middle and late Holocene were possibly on the order of several meters (from 3 to -2-3 m in the Black Sea and from 5 to -2-3 m in the White Sea). Lower estimates of regressive stages are principally derived from archaeological data on ancient settlements in tectonically submerging deltaic areas and cannot be regarded as reliable.Palaeohydrological analysis does not indicate that intensive (15-25 m or greater) sea level fluctuations were present in the Black Sea or in the White Sea during the middle and late Holocene. Instead, such analysis provides independent evidence to support the argument that significant differences in water level between the Black Sea and the Mediterranean could not be maintained for an extended period of time

Geomorphologic evolution of a coastal karst: the Gulf of Orosei (central-east Sardinia, Italy), 2004, De Waele, Jo

In the past ten years cave surveying has allowed better understanding of speleogenesis in the Orosei Gulf (Central-East Sardinia, Italy), one of the most important coastal karst areas of Italy. Surface geomorphologic research has been accompanied by subterranean and submarine landform analysis in order to try and understand the evolution of this coastal karst since its emersion in Upper Eocene. The main factors influencing the geomorphic processes are lithology, tectonics, palaeo-climate and sea level changes. The study of several important cave systems demonstrates a complex geological history with karst processes that started in Early Tertiary and accelerated during Plio-Quaternary.

Karst in Turkish Thrace: Compatibility between geological history and karst type, 2005, Ekmekci M,
Geographically, Thrace is a region located in southeastern Europe within the territories of Greece, Bulgaria and Turkey. In Turkish Thrace, karst occurs extensively in Eocene limestones, although some limited karst occurs in marble of the metamorphic series of Palaeozoic age. The karstification base is shallow to very shallow and most of the dolines and poljes have been captured by surface streams. Subsurface drainage has been changed to surface drainage in most parts of the region. Caves and cave relicts are concentrated mainly at three different altitudes, and almost all caves are horizontal or sub-horizontal. With these characteristics, Turkish Thrace hosts a distinct type of karst compared to that of other regions of Turkey, and particularly to the well-developed active Taurus karst. In this paper, the author discusses the major controls on karst evolution and consequently the occurrence of the present karst type with special emphasis on the geological history of the region. Tectonically, the area is weakly active, implying that a relatively steady continental uplift together with sea-level changes provided the source of the energy gradient required for karstification. The erosion base is controlled mainly by impermeable units. From the geological history of the region, it is concluded that no abrupt change in the energy gradient occurred due to continental uplift. However, fluctuation in sea level due to climate change has caused more sudden changes, particularly in erosion-base levels. This suggests that, in contrast to other karst provinces of Turkey, the impact of climate change has been more pronounced in this region. Reconstruction of karst evolution on the basis of the geological history of the region suggests that karstification processes have evolved without major interruption during the neotectonic period. Thus, the evolutionary character of the Thracian karst has produced relict karst with relatively local karst aquifers compared to those existing in the Taurus karst region. Morphological and hydrological aspects of the area indicate that karstification is in a cessation phase

Sedimentary manganese metallogenesis in response to the evolution of the Earth system, 2006, Roy Supriya,
The concentration of manganese in solution and its precipitation in inorganic systems are primarily redox-controlled, guided by several Earth processes most of which were tectonically induced. The Early Archean atmosphere-hydrosphere system was extremely O2-deficient. Thus, the very high mantle heat flux producing superplumes, severe outgassing and high-temperature hydrothermal activity introduced substantial Mn2 in anoxic oceans but prevented its precipitation. During the Late Archean, centered at ca. 2.75[no-break space]Ga, the introduction of Photosystem II and decrease of the oxygen sinks led to a limited buildup of surface O2-content locally, initiating modest deposition of manganese in shallow basin-margin oxygenated niches (e.g., deposits in India and Brazil). Rapid burial of organic matter, decline of reduced gases from a progressively oxygenated mantle and a net increase in photosynthetic oxygen marked the Archean-Proterozoic transition. Concurrently, a massive drawdown of atmospheric CO2 owing to increased weathering rates on the tectonically expanded freeboard of the assembled supercontinents caused Paleoproterozoic glaciations (2.45-2.22[no-break space]Ga). The spectacular sedimentary manganese deposits (at ca. 2.4[no-break space]Ga) of Transvaal Supergroup, South Africa, were formed by oxidation of hydrothermally derived Mn2 transferred from a stratified ocean to the continental shelf by transgression. Episodes of increased burial rate of organic matter during ca. 2.4 and 2.06[no-break space]Ga are correlatable to ocean stratification and further rise of oxygen in the atmosphere. Black shale-hosted Mn carbonate deposits in the Birimian sequence (ca. 2.3-2.0[no-break space]Ga), West Africa, its equivalents in South America and those in the Francevillian sequence (ca. 2.2-2.1[no-break space]Ga), Gabon are correlatable to this period. Tectonically forced doming-up, attenuation and substantial increase in freeboard areas prompted increased silicate weathering and atmospheric CO2 drawdown causing glaciation on the Neoproterozoic Rodinia supercontinent. Tectonic rifting and mantle outgassing led to deglaciation. Dissolved Mn2 and Fe2 concentrated earlier in highly saline stagnant seawater below the ice cover were exported to shallow shelves by transgression during deglaciation. During the Sturtian glacial-interglacial event (ca. 750-700[no-break space]Ma), interstratified Mn oxide and BIF deposits of Damara sequence, Namibia, was formed. The Varangian ([identical to] Marinoan; ca. 600[no-break space]Ma) cryogenic event produced Mn oxide and BIF deposits at Urucum, Jacadigo Group, Brazil. The Datangpo interglacial sequence, South China (Liantuo-Nantuo [identical to] Varangian event) contains black shale-hosted Mn carbonate deposits. The Early Paleozoic witnessed several glacioeustatic sea level changes producing small Mn carbonate deposits of Tiantaishan (Early Cambrian) and Taojiang (Mid-Ordovician) in black shale sequences, China, and the major Mn oxide-carbonate deposits of Karadzhal-type, Central Kazakhstan (Late Devonian). The Mesozoic period of intense plate movements and volcanism produced greenhouse climate and stratified oceans. During the Early Jurassic OAE, organic-rich sediments host many Mn carbonate deposits in Europe (e.g., Urkut, Hungary) in black shale sequences. The Late Jurassic giant Mn Carbonate deposit at Molango, Mexico, was also genetically related to sea level change. Mn carbonates were always derived from Mn oxyhydroxides during early diagenesis. Large Mn oxide deposits of Cretaceous age at Groote Eylandt, Australia and Imini-Tasdremt, Morocco, were also formed during transgression-regression in greenhouse climate. The Early Oligocene giant Mn oxide-carbonate deposit of Chiatura (Georgia) and Nikopol (Ukraine) were developed in a similar situation. Thereafter, manganese sedimentation was entirely shifted to the deep seafloor and since ca. 15[no-break space]Ma B.P. was climatically controlled (glaciation-deglaciation) assisted by oxygenated polar bottom currents (AABW, NADW). The changes in climate and the sea level were mainly tectonically forced

Relative Sea-Level Changes Recorded on an Isolated Carbonate Platform: Tithonian to Cenomanian Succession, Southern Croatia, 2006, Husinec Antun, Jelaska Vladimir,
Superb sections of Tithonian to Cenomanian carbonates of the Adriatic (Dinaric) platform are exposed on the islands of southern Croatia. A succession approximately 1,800 m thick consists exclusively of shallow-water marine carbonates (limestone, dolomitized limestone, dolomite, and intraformational breccia), formed in a protected and tectonically stable part of the platform interior. Several phases of exposure and incipient drowning are recorded in the platform interior. Four are crucial for understanding the Late Jurassic to mid-Cretaceous evolution of the wider peri-Adriatic area: (1) latest Jurassic-earliest Cretaceous sea-level fall, (2) Aptian drowning, followed by (3) Late Aptian platform exposure, and (4) Late Albian-Early Cenomanian sea-level fall. Deciphering these complex events from the vertical and lateral facies distribution has led to an evaluation of facies dynamics and construction of a relative sea-level curve for the study area. This curve shows that long-term transgression during the Early Tithonian, Hauterivian, Early Aptian, and Early Albian, resulted in generally thicker beds deposited in subtidal environments of lagoons or shoals. Regression was characterized by shallowing-upward peritidal parasequences, with well-developed tidal-flat laminites commonly capped by emersion breccia and/or residual clay sheets (Early Berriasian, Barremian, Late Aptian, Late Albian). The southern part of the Dinarides was tectonically quiet during the Tithonian through Aptian; sea-level oscillations appear to have been the primary control on facies stacking. Some correlation exists between local sea-level fluctuations and the published global eustasy charts for the Tithonian through Aptian. A significant departure is recognized at the Albian-Cenomanian transition, suggesting that it was influenced by tectonics associated with the disintegration of the Adriatic (Dinaric) platform

The deepest cave in the world in the Arabika Massif (Western Caucasus), 2008, Klimchouk A. B. , Samokhin G. V. & Kasjan Yu. M.

Arabika is an outstanding high-mountain karst massif in the Western Caucasus composed of Lower Cretaceous and Upper Jurassic limestones continuously dipping southwest to the Black Sea shore and plunging below the sea level. The central sector (elevations within 2000-2700 m) is characterized by pronounced glacio-karstic landscape and hosts several deep caves including the deepest cave in the world (Krubera-Voronja Cave) recently explored to the depth of -2191 m.  Dye tracing experiments conducted in 1984-1985 revealed that the Krubera Cave area is hydraulically connected with major springs at the Black Sea shore and the submarine discharge, with the flow directed across major fold structures. Krubera Cave has an extremely steep profile and reveals a huge thickness of the vadose zone. Its lower boundary is at elevation of about 110 m, which suggests a very low overall hydraulic gradient of 0.007-0.008. Reported low salinity groundwater tapped by boreholes in the shore area at depths 40-280, 500, 1750 and 2250 m, which suggests the existence of deep flow system with vigorous flow. Submarine discharge in the Arabika coast is reported at depths up to ca. 400 m bsl. Huge closed submarine depression is revealed at the sea-floor in front of Arabika with the deepest point of ca. 400 m bsl. These facts point to a possibility that the main karst system in Arabika could have originated in response to the Messinian salinity crisis (5.96 – 5.33 Myr) when the Black Sea could have almost dried up, similarly to the adjacent Mediterranean where the sea level drop up to 1600 m is well established. Further development of the huge vadose zone and a super-deep cave have been caused by subsequent uplifts during Pliocene-Pleistocene, highly differential between the shore sector (0.1-0.2 km of total uplift) and the central sector (2-2.5 km) of Arabika.

Comparison of 14C and U-Th ages of two Holocene phreatic overgrowths on speleothems from Mallorca (Western Mediterranean): Environmental implications, 2011, Tuccimei P. , Strydonck M. V. , Giné, S A, Giné, S J. , Soligo M. , Villa I. M. , Fornó, S J. J.

This investigation reports on the comparison between ICP-MS U-Th and AMS 14C ages of Phreatic Overgrowths on Speleothems (POS) from two different caves on the island of Mallorca (Spain). These speleothem encrustations form at the water table of coastal caves in a low-amplitude tide-controlled microenvironment and are used to reconstruct past sea level changes. The aim of this study is to evaluate if this particular type of speleothem is datable using 14C method and to investigate possible problems connected with the incorporation of dead carbon inherited from the dissolution of 14C-free limestone. The results show that 14C ages are strongly site dependent and appear related to local residence time of water infiltration through the soil and epikarst. When short transit time and limited interaction with soil and bedrock, as in Cova de Cala Varques A, the so-called “reservoir” effect is negligible and 14C and U-Th ages corresponds within the error range. When the residence time is longer, as in Cova des Pas de Vallgornera, 14C ages are steadily 2,300-2,400 years older than the U-Th data, as shown by the mean value (25%) of estimated percent dead carbon proportions and by higher and better correlated contents of major and trace elements in the vadose support of this speleothem encrustation. The potential use of this multi-method approach to paleoenvironmental studies is also suggested.

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