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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 convection is the process whereby heat is carried along with the flowing ground water [22].?

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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 oligocene (Keyword) returned 59 results for the whole karstbase:
Showing 1 to 15 of 59
GHOST-ROCK KARSTIFICATION IN ENTRE-DEUX-MERS (GIRONDE, FRANCE), IMPLICATIONS FOR KARSTOGENESIS AND KARSTIC MORPHOLOGY, , Dubois Caroline, Lans Benjamin, Kaufmann Olivier, Maire Richard, Quinif Yves

The formation of the Oligocene « calcaires à Astéries » in the region of « Entre-deux-Mers » is affected by a karstification with subhorizontal caves that drained rivers from swallow-holes to resurgences. Observations in quarries show that ghost-rock alterites are present. This paper describes the ghost-rocks in the quarry of Piquepoche exploiting the Frontenac stone. We have studied horizontally developed ghost-rocks with vertical extensions still containing the residual alterite. They can be badly consolidated calcarenites up to soft material which has been sampled. Speleogenesis is reviewed in the frame of the mechanical erosion of the alterite of a horizontal ghost-rock followed by an incision by free-flowing waters which form a passage with promontories and potholes. Finally, we show that ceiling anastomoses can form by ghost-rock karstification.


Morphology of New Zealand Limestone Caves , 1963, Laird, M. G.

Limestone caves in New Zealand can be divided into two distinct groups : those developed in the nearby flat-lying limestone of Oligocene age, and those formed in the strongly folded Mt. Arthur Marble of Upper Ordovician age. Caves formed in Oligocene limestone are typically horizontal in development, often having passages at several levels, and are frequently of considerable length. Those formed in Mt. Arthur Marble have mainly vertical development, some reaching a depth of several hundred feet. Previous research into the formation and geological history of New Zealand cave systems is discussed briefly, and the need for further work is emphasised.


Les palokarsts des Alpes occidentales du Trias l'Eocne, 1984, Guendon, J. L.
WESTERN ALPS PALEOKARSTS FROM TRIASSIC TO EOCENE - In western Alps, before complete emersion during the Oligocene and Miocene, the marine sedimentation has been locally interrupted by three important continental phases: 1/ during Early Jurassic, in "brianonnais" domain; 2/during middle Cretaceous, in Provence area; 3/ during early Tertiary, in subalpine range and Jura. These locally and temporary regression are the consequence of tectonic activities in relation to the movements of eurasiatic and italo-african plates, which are at the edge of the alpine oceanic basin (Tethys). After an abstract on the tectonic and sedimentological history of western Alps, a description is given of continental formations (bauxites, fire-clay, clay with flints, siderolitic formations, white and ochrous sands, siliceous and ferruginous crusts) and karst phenomena elaborated during these regressions.

La karstification profonde dans le Jura partir des observations faites lors du percement du tunnel du LFP (Ain et canton de Genve), 1990, Fourneaux J. Cl. , Landru B. , Sommeria L.
THE DEEP KARSTIFICATION IN THE JURA from observations collected during the digging of the LEP gallery, Ain (France) and district of Geneva (Switzerland) - The LEP tunnel drilling, in part under the first Jura range (north of Geneva), in lower Cretaceous limestone formations, gave the opportunity of many observations about the deep karstification, the connection between these deep forms and the active karst, and also about the karstic fillings. It is possible to find 3 kind of deposits: the first is green and dating from Cretaceous, the second is red and dating from Oligocene, the third is brown and dating from Quaternary. The karstification is developed under the base level and an explanation of this development is given here. But the hydrogeologic behaviour of these formations is in connection with jointing, like a tracing experiment shown it. If in surface, a big karstic spring have a flow varying from 10L/s to 10m3/s, in the tunnel the flow did never overpass 180L/s.

Le karst alpin des Mts. Retezat (Carpathes mridionales, Roumanie), 1991, Badescu, D.
THE ALPINE KARST 0F RETEZAT M0UNTAINS (ROMANIA) - The limestone area of the Retezat Mountains (2079 m), in the Carpathian range (Transylvania), is the principal alpine karst of Romania. It is formed by a syncline structure of jurassic limestone covering a crystalline precambrian basement. The mountain climate is wet (1400 mm/year) and continental. The glacio-karstic morphology (glacial cirque, dry valleys) is developed on a tertiary polygenic surface folded and uplifted since the Oligocene and Neogene. The catchment basin (85 km2) feeds the Izvorul Cernei karst spring (0,5-10 m3/s), the most important of Romania. Water tracings (s = 55 m/h) and statistical studies on caves suggest the development of a complex karst system. 50% of underground waters come from the running off on the precambrian basement and explain the rate of sodium. The majority of the potholes and glacires are situated above 1700m; the deepest is Stna Tomii cave (-136m) with a 115m direct pit.

Karstification et volution palogographique du Jura, 1991, Bienfait, P.
KARSTIFICATION AND PALEOGEOGRAPHICAL EVOLUTION OF THE JURA (Fr.) - The karstification started at the beginning of the Tertiary, and the process is still going on today. During the Eocene, modifications brought about under the tropical climate resulted in siderolithic deposits (siliceous sands, ferruginous soils), which can be found in some fossil karsts. In the Oligocene, active tectonics modified the Eocene surface. Erosion during the Miocene levelled the Jura Mountains into a peneplain even though the climate remained tropical. Toward the end of the Miocene, present-day structure and landforms were produced when the main folding, subjected at the same time to powerful erosion, occurred. During the Upper Pleistocene the climate became cooler and wetter. At least two glacial periods have been recognised in the Pleistocene. Present-day karst landforms and most of the caves can be considered as being shaped during the Plio-Quaternary. The karst fillings of the Quaternary provide evidence of the extension of the Wrm and Riss glaciers.

KARST HYDROGEOLOGY OF THE TAKAKA VALLEY, GOLDEN BAY, NORTHWEST NELSON, 1991, Mueller M. ,
Upper Ordovician Arthur Marble and Oligocene Takaka Limestone contain extensive phreatic cave systems beneath the Takaka valley and Golden Bay. Half of all water flows in the Takaka valley pass through subterranean drainage conduits in carbonate rock. New Zealand's largest freshwater springs, the Waikoropupu Springs, are one surface expression of these karst systems. Other characteristics are dolines and submarine springs. A paleocave system developed in the Arthur Marble during the formation of the northwest Nelson peneplain in the Late Cretaceous and early Tertiary. Subsequent subsidence of the peneplain, and deposition of Motupipi Coal Measures, Takaka Limestone, and Tarakohe Mudstone, was followed by folding and faulting of the sequence in the Kaikoura Orogeny. Uplift and erosion in the Pleistocene brought the two carbonate rock formations within reach of groundwater movements. The paleocave system in Arthur Marble was reactivated during periods of glacial, low sea levels, and a smaller cave system formed in the overlying Takaka Limestone. Both systems interact and extend to more than 100 m below present sea level, forming the Arthur Marble - Takaka Limestone aquifer

GENERAL CENOZOIC EVOLUTION OF THE MALDIVES CARBONATE SYSTEM (EQUATORIAL INDIAN-OCEAN), 1992, Aubert O, Droxler Aw,
Analyses and interpretation of an industrial multi-channel seismic grid, a 2.3 km-deep industrial well (NMA-1) and two ODP (Sites 715 and 716), have generated new insights into the evolution of the Maldives carbonate system, Equatorial Indian Ocean. The present physiography of the Maldives Archipelago, a double chain of atolls delineating an internal basin, corresponds only to the latest phase of a long and dynamic evolution, far more complex than the simple vertical build-up of reef caps on top of thermally subsiding volcanic edifices. Through the Cenozoic evolution of the Maldives carbonate system, distinct phases of vertical growth (aggradation), exposure, regional or local drowning, and recovery of the shallow banks by lateral growth (progradation) have been recognized. The volcanic basement underlying the Maldives Archipelago is interpreted to be part of a volcanic ridge generated by the northern drift of the Indian plate on top of the hotspot of the island of Reunion. The volcanic basement recovered at well NMA-1 and ODP Site 715 has been radiometrically dated as 57.2 1.8 Ma (late Paleocene) by 40Ar-39Ar. Seismic and magnetic data indicate that this volcanic basement has been affected by a series of NNE-SSW trending subvertical faults, possibly associated with an early Eocene strike-slip motion along an old transform zone. The structural topography of the volcanic basement apprears to have dictated the initial geometry of the Eocene and early Oligocene Maldives carbonate system. Biostratigraphic analyses of samples, recovered by drilling in Site 715 and exploration well NMA-1, show that the Maldives shallow carbonate system was initiated during the early Eocene on top of what were originally subaerial volcanic edifices. The Eocene shallow carbonate sequence, directly overlying the volcanic basement at NMA-1, is dolomitized and remains neritic in nature, suggesting low subsidence rates until the early Oligocene. During this first phase of the Maldives carbonate system evolution, shallow carbonate facies aggraded on top of basement highs and thick deep-water periplatform sediments were deposited in some central seaways, precursors of the current wider internal basins. In the middle Oligocene, a plate reorganization of the equatorial Indian Ocean resulted in the segmentation of the hotspot trace and the spreading of the Maldives away from the transform zone. This plate reorganization resulted in increasing subsidence rates at NMA-1, interpreted to be associated with thermal cooling of the volcanic basement underlying the Maldives carbonate system. This middle Oligocene event also coincides with a regional irregular topographic surface, considered to represent a karst surface produced by a major low-stand. Deep-water carbonate facies, as seen in cuttings from NMA-1, overlie the shallow-water facies beneath the karst surface which can, therefore, be interpreted as a drowning unconformity. In the late Oligocene, following this regional deepening event, one single central basin developed, wider than its Eocene counterparts, and the current intraplatform basin was established. Since the early to middle Miocene, the shallow carbonate facies underwent a stage of local recovery by progradation of neritic environments towards the central basin. The simultaneous onset in the early middle Miocene of the monsoonal wind regime may explain the development of bidirectional slope progradations in the Maldives. During the late Miocene and the early Pliocene, several carbonate banks were locally drowned, whereas others (i.e. Male atoll) display well-developed lateral growth through margin progradations during the same interval. Differential carbonate productivity among the atolls could explain these diverse bank responses. High-frequency glacialeustatic sea-level fluctuations in the late Pliocene and Pleistocene resulted in periodic intervals of bank exposure and flooding, and developed the present-day physiography of atolls, with numerous faros along their rims and within their lagoons

CAYMANITE, A CAVITY-FILLING DEPOSIT IN THE OLIGOCENE MIOCENE BLUFF FORMATION OF THE CAYMAN ISLANDS, 1992, Jones B. ,
Caymanite is a laminated, multicoloured (white, red, black) dolostone that fills or partly fills cavities in the Bluff Formation of the Cayman Islands. The first phase of caymanite formation occurred after deposition, lithification, and karsting of the Oligocene Cayman Member. The second phase of caymanite formation occurred after joints had developed in the Middle Miocene Pedro Castle Member. Caymanite deposition predated dolomitization of the Bluff Formation 2-5 Ma ago. Caymanite is formed of mudstones, wackestone, packstones, and grainstones. Allochems include foraminifera, red algae, gastropods, bivalves, and grains of microcrystalline dolostone. Sedimentary structures include planar laminations, graded bedding, mound-shaped laminations, desiccation cracks, and geopetal fabrics. Original depositional dips ranged from 0 to 60-degrees. Although caymanite originated as a limestone, dolomitization did not destroy the original sedimentary fabrics or structures. The sediments that formed caymanite were derived from shallow offshore lagoons, swamps, and possibly brackish-water ponds. Pigmentation of the red and black laminae can be related to precipitates formed of Mn, Fe, Al, Ni, Ti, P, K, Si, and Ca, which occur in the intercrystalline pores. These elements may have been derived from terra rossa, which occurs on the weathered surface of the Bluff Formation. Caymanite colours were inherited from the original limestone. Stratigraphic and sedimentologic evidence shows that sedimentation was episodic and that the sediment source changed with time. Available evidence suggests that caymanite originated from sediments transported by storms onto a highly permeable karst terrain. The water with its sediment load then drained into the subsurface through joints and fissures. The depth to which these waters penetrated was controlled by the length of the interconnected cavity system. Upon entering cavities, sedimentation was controlled by a complex set of variables

VOID-FILLING DEPOSITS IN KARST TERRAINS OF ISOLATED OCEANIC ISLANDS - A CASE-STUDY FROM TERTIARY CARBONATES OF THE CAYMAN-ISLANDS, 1992, Jones B. ,
Caves, fossil mouldic cavities, sinkholes and solution-widened joints are common in the Cayman and Pedro Castle members of the Bluff Formation (Oligocene Miocene) on Grand Cayman and Cayman Brac because they have been subjected to repeated periods of karst development over the last 30 million years. Many voids contain a diverse array of sediments and/or precipitates derived from marine or terrestrial environs, mineral aerosols, and groundwater. Exogenic sediment was transported to the cavities by oceanic storm waves, transgressive seas, runoff following tropical rain storms and/or in groundwater. At least three periods of deposition were responsible for the occlusion of voids in the Cayman and Pedro Castle members. Voids in the Cayman Member were initially filled or partly filled during the Late Oligocene and Early Miocene. This was terminated with the deposition of the Pedro Castle Member in the Middle Miocene. Subsequent exposure led to further karst development and void-filling sedimentation in both the Cayman and Pedro Castle members. Speleothems are notably absent. The void-filling deposits formed during these two periods, which were predominantly marine in origin, were pervasively dolomitized along with the host rock 2 5 million years ago. The third period of void-filling deposition. after dolomitization of the Bluff Formation, produced limestone, various types of breccia, terra rossa, speleothemic calcite and terrestrial oncoids. Most of these deposits formed since the Sangamon highstand 125 000 years ago. Voids in the present day karst are commonly filled or partly filled with unconsolidated sediments. Study of the Bluff Formation of Grand Cayman and Cayman Brac shows that karst terrains on isolated oceanic islands are characterized by complex successions of void-filling deposits that include speleothems and a variety of sediment types. The heterogenetic nature of these void-filling deposits is related to changes in sea level and climatic conditions through time

Rospo Mare (Adriatique), un palokarst ptrolier du domaine mditerranen, 1993, Dubois P. , Sorriaux P. , Soudet H. J.
The oil paleokarst of Rospo Mare (Adriatic Sea) The oil field of Rospo Mare is located in the Adriatic Sea, 20 km of the Italian coast. The reservoir lies at the depth of 1300m and consists of a paleokarst of Oligocene to Miocene age, which developed within Cretaceous limestones, now covered with 1200m of mio-pliocene sequences. The oil column is about 140m high. The karstic nature of the reservoir was identified through vertical, cored drill holes which allowed the analysis of the various solutional features and the sedimentary infilling (speleothems, terra rossa, marine clays), as well as their vertical distribution. Erosion morphology at the top of the karst is highly irregular, including paleovalleys as well as many pit-shaped sinkholes. Observations concerning the upper part of the reservoir were compared to a paleokarst of the same age, outcropping widely onshore, in nearby quarries. Detailed knowledge of that morphology through geophysics helped to optimise the development of the field through horizontal drilling. The paleokarst of Rospo Mare is an integral part of the pre-miocene paleokarst assemblages of the periphery of the Mediterranean, which were formed in tropical conditions.

Karst origin of the upper erosion surface in the Northern Judean Mountains, Israel, 1993, Frumkin, A.
The upper erosion surface in the northern Judean Mountains is actively karstified, in the vadose zone and on the surface. The karst valleys become gradually covered with Terra Rossa which inhibits further denudation underneath the impermeable cover. Higher solution rates in the elevated areas keep the erosion surface relatively flat. The main characteristics of the area which dominate karst processes are fissured carbonate rocks with some insolubles and aeolian contribution, non arid climate and moderate relief. The erosion surface developed probably since the Oligocene regression. The Pleistocene uplift of the mountain backbone increased the relief and reduced the area of the karst plateau.

RELATIONSHIP BETWEEN FRACTURES AND KARSTIFICATION - THE OIL-BEARING PALEOKARST OF ROSPO MARE (ITALY), 1994, Soudet H. J. , Sorriaux P. , Rolando J. P. ,
The Rospo Mare oil field is located in the Adriatic Sea, 20 km off the Italian coast. The reservoir lies at a depth of 1300 m and consists of a paleokarst oi Oligocene to Miocene age which developed within Cretaceous limestones, now covered by 1200 m of Mio-Pliocene sequences. The oil column is about 140 m 8 high. The karstic nature of the reservoir was identified through vertical, cored drill holes which allowed us to analyse the various solution features and the sedimentary infilling (speleothems, terra rossa, marine clays), as well as their vertical distribution. Erosion morphology at the top of the karst is highly irregular, including in particular paleovalleys as well as many pit-shaped sink holes. Detailed geophysical knowledge of that morphology helped to optimize the development of the field through horizontal drilling. Observations concerning the upper part of the reservoir were compared to a palaeokarst of the same age, outcropping widely onshore, in quarries located nearby. The Rospo Mare paleokarst is an integral part of the ante Miocene paleokarst assemblages of the periphery of the Mediterranean which were formed in tropical conditions. Only the fractures enhanced by meteoric water during the formation of the karat are important for reservoir connectivity. During the formation of the karst there were several phases of dissolution and infilling which modified the geometry of the open fissures and only these fractures play an important role in the reservoir drainage. Vertically we can distinguish three very different zones from top to bottom: at the top the epikarst (0-35 m) in a zone of extension. All the fractures have been enlarged by dissolution but the amount of infilling by clay is substantial. The clays are derived either from alteration of the karat fabric or by deposition during the Miocene transgression; the percolation zone (15-45 m) is characterized by its network of large fractures vertically enlarged by dissolution which corresponds to the relict absorption zones in the paleokarst. These fractures, which usually have a pluridecametric spacing, connect the epi-karst with the former sub-horizontal river system. This zone has been intersected by the horizontal wells during the field development. In this zone there are local, horizontal barriers oi impermeable clay which can block vertical transmissibility. In these low permeability zones the vertical fractures have not been enlarged due to dissolution hence the horizontal barrier; the zone of underground rivers (35-70 m) is characterized by numerous horizontal galleries which housed the subterranean ground water circulation. When these fissures are plurimetric in extent this can lead to gallery collapse with the associated fill by rock fall breccia. This can partly block the river system but always leaves a higher zone of free circulation with high permeabilities of several hundreds of Darcys. These galleries form along the natural fracture system relative to the paleohydraulic gradient which in some cases has been preserved. The zone below permanent ground water level with no circulation of fluids is characterized by dissolution limited to non-connected vugs. Very locally these fissures can be enlarged by tectonic fractures which are non-connected and unimportant for reservoir drainage. Laterally, only the uppermost zone can be resolved by seismic imaging linked with horizontal well data (the wells are located at the top of the percolation zone). The Rospo Mare reservoir shows three distinct horizontal zones: a relict paleokarst plateau with a high index of open connected fractures, (area around the A and B platforms); a zone bordering the plateau (to the north-east of the plateau zone) very karstified but intensely infilled by cap rock shales (Miocene - Oligocene age); a zone of intensely disturbed and irregular karst paleotopography which has been totally infilled by shales. The performance of the production wells is dependent on their position with respect to the three zones noted above and their distance from local irregularities in the karst paleotopography (dolines, paleovalleys)

HIGH-RESOLUTION SEISMIC EXPRESSION OF KARST EVOLUTION WITHIN THE UPPER FLORIDIAN AQUIFER SYSTEM - CROOKED LAKE, POLK COUNTY, FLORIDA, 1994, Evans Mw, Snyder Sw, Hine Ac,
We collected 43 km of high resolution seismic reflection profiles from a 14.5-hectare lake in the central Florida sinkhole district and data from three adjacent boreholes to determine the relationship between falling lake levels and the underlying karst stratigraphy. The lake is separated from karstified Paleogene to early Neogene carbonates by 65-80 m of siliciclastic sands and clays. The carbonate and clastic strata include three aquifer systems separated by clay-confining units: a surficial aquifer system (fine to medium quartz sand in the upper 20-30 m), the 25-35 m thick intermediate aquifer system (in Neogene siliciclastics), and the highly permeable upper Floridan aquifer system in Paleogene to early Neogene limestones. Hydraulic connection between these aquifer systems is indicated by superjacent karst structures throughout the section. Collapse zones of up to 1000 m in diameter and > 50 m depth extend downward from a prominent Middle Miocene unconformity into Oligocene and Upper Eocene limestones. Smaller sinkholes (30-100 m diameter, 10-25 m depth) are present in Middle to Late Neogene clays, sands, and carbonates and extend downward to or below the Middle Miocene unconformity. Filled and open shafts (30-40 m diameter; 10-25 m depth) ring the lake margin and overlie subsurface karst features. The large collapse zones are localized along a northeast-southwest line in the northern ponds and disrupt or deform Neogene to Quaternary strata and at least 50 m of the underlying Paleogene carbonate rocks. The timing and vertical distribution of karst structures are used to formulate a four-stage model that emphasizes stratigraphic and hydrogeologic co-evolution. (1) Fracture-selective shallow karst features formed on Paleogene/early Neogene carbonates. (2) Widespread karstification was limited by deposition of Middle Miocene clays, but vertical karst propagation continued and was focused because of the topographic effects of antecedent karst. (3) Groundwater heads, increase with the deposition of thick sequences of clastics over the semipermeable clays during Middle and Late Neogene time. The higher water table and groundwater heads allowed the accumulation of acidic, organic-rich soils and chemically aggressive waters that percolated down to Paleogene carbonates via localized karst features. (4) After sufficient subsurface dissolution, the Paleogene carbonates collapsed, causing disruption and deformation of overlying strata. The seismic profiles document an episodic, vertically progressive karst that allows localized vertical leakage through the clay-confining units. The spatial and temporal karst distribution is a result of deposition of sediments with different permeabilities during high sea levels and enhanced karst dissolution during low sea levels. Recent decreases in the potentiometric elevation of the Floridan Aquifer System simulates a sea-level lowstand, suggesting that karst dissolution will increase in frequency and magnitude

Etapes et facteurs de la splogense dans le sud-est de la France, 1995, Blanc, J. J.
The examination of karstic erosion surfaces and of some caves presents three stages of unequal duration in the speleogenesis processes : 1) Oldest paleokarsts linked to a tropical and oxydizing climate (Cretaceous, Eocene, Oligocene and Miocene) are affected by the tectonic effects in relation with the western European and liguro-provencal riftings, the mediterranean opening phases and the main karstic levelling. 2) The Messinian crisis, characterized by a significant lowering of the water-table level, is responsible for a major vertical network development and the first canyon sinking phase; hence the erosion of the high surfaces and the drying up of networks. The formation of new over-sized karst is the result of this evolution. 3) From Pliocene (5.3 My) to Quaternary and present time (passive mediterranean margins), the karstic evolution tends towards new drainages and volumes adjusted to the next climatic and eustatic control, with several oscillations and discontinuities. After a compression period, there is a slowing down of the tectogenesis. We can observe orientation flow changes and speleogenesis induced by cold and wet climatic phases. From Tardiglacial times, speleogenesis mechanisms have slowed down.

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