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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. ...

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That open traverse is a traverse which does not close onto a survey point of known coordinates and orientation or onto itself [25].?

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Your search for mediterranean-sea (Keyword) returned 13 results for the whole karstbase:
Paleoclimate and location of the border between Mediterranean climate region and the Saharo-Arabian Desert as revealed by speleothems from the northern Negev Desert, Israel, , Vaks A. , Barmatthews M. , Ayalon A. , Matthews A. , Frumkin A. , Dayan U. , Halicz L. , Mogilabin A. , Schilman B. ,
Speleothem bearing karstic caves of the northern Negev Desert, southern Israel, provides an ideal site for reconstructing the paleoclimate and paleo-location of the border between Mediterranean climate region and the Saharo-Arabian Desert. Major periods of speleothem deposition (representing humid periods) were determined by high resolution 230Th-U dating and corresponding studies of stable isotope composition were used to identify the source of rainfall during humid periods and the vegetation type. Major humid intervals occurred during glacials at 190-150[no-break space]ka, 76-25[no-break space]ka, 23-13[no-break space]ka and interglacials at 200-190[no-break space]ka, 137-123[no-break space]ka and 84-77[no-break space]ka. The dominant rainfall source was the Eastern Mediterranean Sea, with a possible small contribution from southern tropical sources during the interglacial periods. When the interglacial interval rainfall was of Eastern Mediterranean origin, the minimum annual rainfall was ~ 300-350[no-break space]mm; approximately twice than of the present-day. Lower minimum amounts of precipitation could have occurred during glacial periods, due to the cooler temperatures and reduced evaporation. Although during most of the humid periods the vegetation remained steppe with mixed C3 C4 vegetation, Mediterranean C3 type steppe-forest vegetation invaded southward for short periods, and the climate in the northern Negev became closer to Mediterranean type than at present. The climate was similar to present, or even more arid, during intervals when speleothem deposition did not occur: 150-144[no-break space]ka, 141-140[no-break space]ka, 117-96[no-break space]ka, 92-85[no-break space]ka, 25-23[no-break space]ka, and 13[no-break space]ka-present-day.Precipitation increase occurred in the northern Negev during the interglacial monsoonal intensity maxima at 198[no-break space]ka, 127[no-break space]ka, 83[no-break space]ka and glacial monsoonal maxima at 176[no-break space]ka, 151[no-break space]ka, 61[no-break space]ka and 33[no-break space]ka. However, during interglacial monsoonal maxima at 105[no-break space]ka and 11[no-break space]ka, the northern Negev was arid whereas during glacial monsoonal minima it was usually humid. This implies that there is not always synchroneity between monsoonal activity and humidity in the region.Oxygen isotopic values of the northern Negev speleothems are systematically lower than contemporaneous speleothems of central and northern Israel. This part is attributed to the increased rainout of the heavy isotopes by Rayleigh fractionation processes, possibly due to the farther distance from the Mediterranean coast

Quaternary Paleoclimatology of the Black Sea basin, 1979, Schrader Hans Joachim,
The occurrence of polyhaline, mesohaline and oligohaline diatom, silicoflagellate, ebridian and chrysomonad populations in late Quaternary Black Sea sediments (DSDP Leg 42B) forms the basis for reconstruction of surface water paleosalinities in the Black Sea basin over the last 3 million years. Four major periods with increased salinites are separated by extended freshwater periods. Based on paleosalinites, indicators of trophic freshwater conditions and changes in diatom species diversity, a correlation is made to the northern Europian glacial--interglacial stratigraphy and this correlation is used to place paleoenvironmental events into a chronostratigraphy. The `synchronous' late Quaternary occurrence of sediments rich in organic carbon in both the Eastern Mediterranean and the Black Sea supports this interpretation.Three different stages in the interaction between the Black Sea and the Eastern Mediterranean Sea are defined: Stage A (exchange of freshwater and marine water similar to the present day flux) during the Holocene, Eemian, Holsteinian and Pliocene; Stage B (freshwater conditions with only occasional marine spills) during the Saalian, the Waalian, the Tiglian and the Praetiglian; and Stage C (freshwater conditions with no inflow of marine waters) during the Weichselian, the Elsterian and Eburonian

Palaeogeographic environment during the desiccation of the Black Sea, 1983, Kojumdgieva Emilia,
During the latest Chersonian (about 10.3 m.y. ago) tectonic movements took place leading to an elevation of the Crimean-Caucasian chain and to an isolation of the Fore-Caucasian part of the Black Sea Basin. This part of the basin had been draining the rivers of the Russian Platform and after the isolation it became desalinized, while the main part of the Black Sea Basin was almost desiccated and evaporites, mainly dolomites, formed in it due to the predominant calcium---magnesium---carbonate composition of the Chersonian Sea waters. These dolomites are found in the drillings of DSDP Leg 42B and are confirmed geophysically.The tectonic movements during the latest Chersonian led to the formation of a series of grabens along which the Mediterranean Sea invaded the north Aegean area and a little later (during the Early Maeotian) the Black Sea

Scuba observations of standstill levels in Elba Island (ltaly) and in Marie-Galante (West Indies). A worldwide sequence?, 1999, Collinagirard J,
Scuba observations (0 to -60 m) in Provence and Corsica and new data from Elba Island (Italy) indicate the bathymetric location of eustatic erosion levels in the Mediterranean Sea. A general sketch is given (standstill levels at-ii m, -17 m, -25 m, -35 m, -45 m, -50 m/55 m, -100 m). Isotopic data suggest contemporaneity of -100 m and -55 m levels with the two slow-down phases of Holocene transgression documented in Barbados and Tahiti coring (MWP-1A and 1B). Transgression acceleration after 14 000 BP explains the conservation of these littoral morphologies. Tectonics or isostasic movements (never more than 5 m) are prooved by differences observed in different areas of the world

Continental Oxygen Isotopic Record of the Last 170,000 Years in Jerusalem, 1999, Frumkin A, Ford Dc, Schwarcz Hp,
A long radiometrically dated oxygen isotopic record of continental climatic variations since the penultimate glaciation was obtained from a stalagmite deposited in a sealed cave in Jerusalem. This record shows that speleothems have the potential of assigning dates to long- and short-term climatic events, with possible refining of Milankovitch tuning of ice and marine records which themselves are not datable. Short-term (~1000-yr) events are very significant in the region, reaching ~50% of glacial/interglacial fluctuations. The Mediterranean Sea was the most probable source of local precipitation throughout the last glacial cycle

Mn-Fe deposits in shallow cryptic marine environment: examples in northwestern Mediterranean submarine caves, 2001, Allouc J, Harmelin Jg,
Black coating of hard substrates by Mn and Fe oxides has long been reported from shallow, dark, submarine caves. However, these littoral metallic deposits have never been studied in detail, despite expected analogies with deep-sea polymetallic crusts. Submarine caves are characterized by darkness and low rates of exchanges with the open sea. Lack of primary production and confinement of inner water bodies result in marked oligotrophy and extremely reduced biomass, i.e. conditions close to those prevailing in deep-sea habitats. Field evidences suggested that the formation of Mn-Fe coatings was closely tied to these particular environmental conditions. The goal of this study was to examine the detailed features of Mn-Fe coatings from dark caves with different local conditions, and to try to identify the processes responsible for their deposition. Study sites and methods Three sublittoral, single-entrance, caves were sampled by scuba diving along the coasts of Provence (France, Mediterranean Sea) (fig. 1). The first site is a large karstic cave (Tremies Cave, 16 m depth at entrance floor, 60 m long; Marseille-Cassis area) with an ascending profile which results in a buffered thermal regime and markedly oligotrophic conditions due to warm water trapping in its upper part (fig. 1 and 2). Wall fragments were sampled at 30 m (medium confinement : zone B) and 60 in (strong confinement : zone C) from the cave entrance. The second site is a large tubular cavity open in conglomerate formations (3PP Cave, 15 m depth at entrance floor, 120 m long; La Ciotat) with a descending profile which results in relative permanence of winter temperatures within the inner parts, complex water circulation and presumed greater input of sedimented particles than in the preceding cave (fig.1 and 2). Wall samples were taken at 25 m, 70 in and 100 m from entrance. The third site is a small, horizontal, cave open in quartzite formations (Bagaud Cave, 7 in depth at entrance floor, about 10 m long; WNW of Port-Cros Island, bay of Hyeres). Sampling was performed on walls of a narrow corridor between an anterior room and a smaller inner room. A sporadic outflow of continental waters is located in the inner room. The samples were preserved in 50% ethylic alcohol or studied soon after their sampling. Before carbon coating and SEM examination, or microanalyses with SEM-associated spectrometers, they were treated in a 33% Chlorox solution and thereafter washed in demineralized water and dried. Micromorphology At low-medium magnification (<20,000), the aspect of coatings varies between caves and, especially, between inner-cave locations. All the described structures are made up of Mn and Fe oxides. In Tremies Cave, coatings of walls from zone B are composed of irregular erected constructions (height : 10s to 100s μm) formed by the aggregation of roughly ovoid primary concretions of about 10 μm (fig. 3). The surface of those primary concretions displays numerous lacunose to reticulate films (pores, about 0.5 μm in diameter, are often subrounded). Remnants of these films and organomorphic corpuscles occur also within the primary concretions (fig. 4). On younger substrates (broken wall exposed since 1970), primary concretions are poorly developed and no prominent construction is visible (fig. 5). In more confined conditions (zone C), the erected constructions of ancient coatings are smaller and less numerous than in zone B but are well individualized (fig. 6). In this zone: C, besides some remnants of lacunose to reticulate films (fig. 7), there is an appearance of filaments and ovoid corpuscles (height/width : 10-30/5-15 μm), which seem to be linked to filaments by a short stalk (fig. 8). In 3 PP Cave, at 25-70 m from entrance, wall coatings present porous heaps of primary concretions (fig. 9). The surface and the inside of the latter comprise remnants of lacunose to reticulate films that evoke those observed in Tremies Cave (fig. 10 and 11). On younger substrates (hard parts of sessile invertebrates), coatings are restricted to micrometric organomorphic corpuscles with some remnants of lacunose or fibrous films (fig. 12). At 100 in from the entrance, coatings are shaped by numerous erected constructions, more or less coalescing (fig. 13). Besides remnants of lacunose films, the primary concretions contain interlacing filaments (diameter : 0.2-0.3 μm) forming cords or veils (fig. 14). In Bagaud Cave, the primary concretions are aggregated in irregular heaps (fig. 15). Lacunose films are particularly frequent and tend to form three-dimensional mamillated structures that were not observed in the other caves (fig. 16). In particular, there is an appearance of tubular structures (fig. 17) and of numerous hemispheroidal structures (diameter : 4-5 μm) with an upper orifice (fig. 18 and 19). At higher magnification (20,000), whatever the cave and inner-cave location, the aspect of oxide deposits is rather smooth or, especially, microgranular (fig. 20). Mineral composition The composition of coatings is different between caves and according to their inner-cave location. In both large caves (Tremies and 3 PP), the Mn/Fe ratio increases with the distance from the cave entrance, i.e. when exchanges with the open sea diminish (fig. 21a). This trend is particularly clear in Tremies Cave, where the confinement gradient is strongly marked. Besides, the Mn/Fe ratio also seems to increase when films are present in the analysed volume (some cubic micrometers) (fig. 21b). In Bagaud Cave, the Mn/Fe ratio reaches high values despite the small size of this cave and its low confinement level. Discussion and conclusions SEM observations suggest that in each studied cave, the Mn-Fe coatings are biosedimentary deposits. Genesis of these deposits is assumed to result mainly from the replacement of biofilms (composed of cells and slime, i.e, of extracellular polymeric substance produced by microorganisms) generated by microbial populations colonizing the cave walls. Considering the darkness of the cave-locations, microbes consist mainly in bacteria, but fungi are probably responsible for the filaments and ovoids corpuscules (evoking sporocysts) occurring in innermost parts. Observations at different scales of the morphological features of oxide deposits reveal a structured organisation which varies along the strong environmental gradients (particularly the confinement level) that occur from the entrance to the innermost parts : erected constructions made up of primary concretions become more and more defined and acquire a pseudo-columnar shape. The aspect of biofilms appears to be controlled by the same environmental parameters. In open or relatively open environments, they frequently show a three-dimensional development (with frequent skullcape-like shapes), while in more confined conditions they exhibit a planar layout. These changes reflect either the adaptation of the slime-producing bacteria to the local trophic resources (correlated to the rate of exchange with the open sea) and water movements, or spatial replacement of taxa. It is assumed that slime (mainly composed of water and exopolysaccharides) induces a local increase of the concentration in dissolved Mn and acts as an ion exchange resin that allows the retention of Mn on the functional groups of EPS. These conditions promote the nucleation of Mn oxide crystallites in the slime. Then. the anionic character of Mn oxides in seawater, and their capacity to catalyse the oxydation of Mn2 to Mn4, allow the process to go on without any other biological intervention; thus, the process of crystal growth becomes possible. In caves where Mn is only supplied by seawater (Tremies and 3 PP), the average value of the Mn/Fe ratio of coatings is negatively correlated to the local availability of nutrients. This trend is probably linked to changes in the selectivity of slimes towards the processes of retention of cations, because this ratio is clearly influenced by the occurrence of biofilms. However, independently from trophic resources, the Mn/Fe ratio can be notably increased when additional Mn is provided by the seeping or flowing of continental waters (Bagaud Cave)

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]

La stratigraphie oligo-miocene et la surface d'erosion messinienne en mer Noire, stratigraphie sismique haute resolution: The Oligo-Miocene stratigraphy and the Messinian erosional surface in Black Se, 2003, Gillet H, Lericolais G, Rehault Jp, Dinu C,
ResumeLa stratigraphie des marges occidentales de la mer Noire est revisee a partir des donnees de sismique multitrace haute resolution des recentes missions franco-roumaines Blason 1 et 2. Les profils, cales par des forages petroliers et DSDP, revelent la presence de plusieurs discontinuites majeures, interpretees comme des surfaces d'erosion tertiaires. D'une part, la discontinuite sismique la plus marquee souligne la base des series miocenes et correspond a une surface dite composite qui integre plusieurs phases erosives successives de l'Oligocene au Pontien. D'autre part, une surface d'erosion messinienne est clairement mise en evidence en mer Noire. Nos resultats confortent l'hypothese de Hsu [Palaeogeogr. Palaeoclimatol. Palaeoecol. 29 (1979) 75-93], qui propose une chute majeure du niveau de la mer Noire au Messinien, parallelement a la crise messinienne en Mediterranee. Pour citer cet article : H.[no-break space]Gillet et[no-break space]al., C. R. Geoscience 335 (2003).AbstractThe stratigraphy of the Black Sea western margin is revisited through seismic data acquired during two French-Romanian surveys. These data are calibrated by industrial and DSDP drillings; they display several major discontinuities regarded as Tertiary erosional surfaces. The major seismic discontinuity underlines the base of Miocene formations and corresponds to a composite surface including at least three erosional phases ranging from Oligocene to Pontian times. Moreover, a Messinian erosional surface is clearly identified. This is in agreement with the Hsu's proposition [Palaeogeogr. Palaeoclimatol. Palaeoecol. 29 (1979) 75-93] suggesting a Messinian sea-level drop of Black Sea related to the Messinian Salinity Crisis described in the Mediterranean Sea. To cite this article: H.[no-break space]Gillet et[no-break space]al., C. R. Geoscience 335 (2003)

The effect of the Messinian Deep Stage on karst development around the Mediterranean Sea. Examples from Southern France, 2004, Audra P, Mocochain L, Camus H, Gilli E, Clauzon G, Bigot Jy,
It is difficult to explain the position and behaviour of the main karst springs of southern France without calling on a drop in the water table below those encountered at the lowest levels of Pleistocene glacio-eustatic fluctuations. The principal karst features around the Mediterranean are probably inherited from the Messinian period ('Salinity crisis') when sea level dropped dramatically due to the closing of the Straight of Gibraltar and desiccation of the Mediterranean Sea. Important deep karst systems were formed because the regional ground water dropped and the main valleys were entrenched as canyons. Sea level rise during the Pliocene caused sedimentation in the Messinian canyons and water, under a low hydraulic head, entered the upper cave levels. The powerful submarine spring of Port-Miou is located south of Marseille in a drowned canyon of the Calanques massif. The main water flow comes from a vertical shaft that extends to a depth of more than 147 in bsl. The close shelf margin comprises a submarine karst plateau cut by a deep canyon whose bottom reaches 1,000 in bsl. The canyon ends upstream in a pocket valley without relation to any important continental valley. This canyon was probably excavated by the underground paleoriver of Port-Miou during the Messinian Salinity Crisis. Currently, seawater mixes with karst water at depth. The crisis also affected inland karst aquifers. The famous spring of Fontaine de Vaucluse was explored by a ROV (remote observation vehicle) to a depth of 308 in, 224 m below current sea level. Flutes observed on the wall of the shaft indicate the spring was formerly an air-filled shaft connected to a deep underground river flowing towards a deep valley. Outcroppings and seismic data confirm the presence of deep paleo-valleys filled with Pliocene sediments in the current Rhone and Durance valleys. In the Ardeche, several vauclusian springs may also be related to the Messinian Rhone canyon, located at about 200 in below present sea level. A Pliocene base level rise resulted in horizontal dry cave levels. In the hinterland of Gulf of Lion, the Cevennes karst margin was drained toward the hydrologic window opened by the Messinian erosional surface on the continental shelf

The Ardeche endokarstic responses to the eustatic variations resulting from the Messinian salinity crisis, 2006, Mocochain L. , Clauzon G. , Bigot J. Y. ,
The Messinian salinity crisis is typically recorded by evaporites in the abyssal plains of the Mediterranean Sea and by canyons incised into the Mediterranean margins and their hinterlands. However, the impacts of crisis on geomorphology and surface dynamics lasted, until. canyons were filled by sediments in the Pliocene (fig. 2). In the mid-Rhone valley, the Ardeche Cretaceous carbonate platform is incised over 600 m by the Rhone Messinian canyon. The canyon thalweg is located - 236 m Lis) (below sea level) in the borehole of Pierrelatte [Demarcq, 1960; fig. 1]. During the Pliocene, this canyon was flooded as a ria and infilled by a Gilbert type fan delta [Clauzon and Rubino, 1992; Clauzon et al., 1995]. The whole Messinian-Pliocene third order cycle [Haq et al., 1987] generated four benchmark levels. The first two are [Clauzon, 1996]: (i) The pre-evaporitic abandonment Surface which is mapped around the belvedere of Saint-Restitut (fig. 1). This Surface is synchronous [Clauzon, 1996] of the crisis onset (5.95 Ma) [Gautier et al., 1994; Krigjsman et al., 1999] and, consequently, is an isochrounous benchmark. (ii) The Messinian erosional surface is also an isochronous benchmark due to the fast flooding [Blanc, 2002] of the Rhone canyon, becoming a ria at 5.32 Ma [Hilgen and Langereis, 1988]. These surfaces are the result of endoreic Mediterranean sea level fall more than a thousand meters below the Atlantic Ocean. A huge accommodation Space (up to more than 1000 in) was created as sea-level rose up to 80 in above its present-day level (asl) during (lie Pliocene highstand of cycle TB 3.4 (from 5.32 to 3.8 Ma). During the Lower Pliocene this accommodation space was filled by a Gilbert fan delta. This history yields two other benchmark levels: (i) the marine/non marine Pliocene transition which is an heterochronous surface produced by the Gilbert delta progradation. This surface recorded the Pliocene highstand sea level; (ii) the Pliocene abandonment Surface at the top of the Gilbert delta continental wedge. Close to the Rhone-Ardeche confluence, the present clay elevations Of file four reference levels are (evolution of base-level synthesized in fig. 4): (1) 3 12 in asl, (2) 236 in bsl, (3) 130 m asl, (4) 190 In A. The Ardeche carbonate platform underwent karstification both surficial and at depth. The endokarst is characterized by numerous cavities organised in networks. Saint-Marcel Cave is one of those networks providing the most coillplete record (fig. 5). It opens out on the northern side of the Ardeche canyon at an altitude of 100 m. It is made up by three superposed levels extending over 45 km in length. The lower level (1) is flooded and functionnal. It extends beneath the Ardeche thalweg down to the depth of 10 m bsl reached by divers. The observations collected in the galleries lead us to the conclusion that the karst originated in the vadose area [Brunet, 2000]. The coeval base-level was necessarily below those galleries. The two other levels (middle (2) and upper (3)) are today abandoned and perched. The middle level is about 115 m asl and the upper one is about 185 m A. They are horizontal and have morphologies specific to the phreatic and temporary phreatic zone of the karst (fig. 6). In literature, the terracing of the Saint-Marcel Cave had been systematically interpreted as the result of the lowering by steps of the Ardeche base-level [Guerin, 1973; Blanc, 1995; Gombert, 1988; Debard, 1997]. In this interpretation, each deepening phase of the base level induces the genesis of the gravitary shaft and the abandonment of the previous horizontal level. The next stillstand of base level leads to the elaboration of a new horizontal level (fig. 7). This explanation is valid for most of Quaternary karsts, that are related to glacio-eustatic falls of sea-level. However Our study on the Saint-Marcel Cave contests this interpretation because all the shafts show an upward digging dynamism and no hint of vadose sections. The same 'per ascensum' hydrodynamism was prevailing during the development of the whole network (figs. 8 and 9). We interpret the development of the Ardeche endokarst as related to the eustatic Messinian-Pliocene cycle TB 3.4/3.5 recorded by the Rhone river. The diving investigations in the flooded part of the Saint-Marcel Cave and also in the vaLlClusian springs of Bourg.-Saint-Andeol reached - 154 in bsl. Those depths are compatible only with the incision of the Messinian Rhone canyon at the same altitude (- 236 m bsl). The Saint-Marcel lower level would have develop at that time. The ascending shaping of levels 2 and 3 is thus likely to have formed during the ensuing sea-level rise and highstand during the Pliocene, in mainly two steps: (i) the ria stage controlled by the Mediterranean sea level rise and stillstand; (ii) the rhodanian Gilbert delta progradation, that controlled the genesis of the upper level (fig. 10)

How much did climate force the Messinian salinity crisis? Quantified climatic conditions from pollen records in the Mediterranean region, 2006, Fauquette S, Suc Jp, Bertini A, Popescu Sm, Warny S, Bachiri Taoufiq N, Perez Villa Mj, Chikhi H, Feddi N, Subally D,
The latest Miocene (5.96 to 5.33[no-break space]Ma) is characterised by an outstanding event: the desiccation of the Mediterranean Sea (Messinian salinity crisis). It has been suggested that this was caused by a tectonic event, with no climatic change playing a role in desiccation. Quantifying the climate of the region during this period will help support or refute this hypothesis. An effective method for reconstructing the climate from Neogene pollen data is the 'Climatic Amplitude Method' based on the modern climatic requirements of plants to interpret fossil data. It has been conceived especially for periods devoid of modern vegetation analogue.Twenty Messinian to Lower Zanclean pollen sequences are now available in the peri-Mediterranean region. Most of them do not cover the whole Messinian interval, particularly those along the Mediterranean shorelines where sedimentation was interrupted during the sea's desiccation. In contrast, sedimentation was almost continuous in such areas as the Atlantic side of Morocco, along the Adriatic coast (including the Po Valley), and to a lesser extent the Black Sea. The Mediterranean sites nonetheless provide a reliable if not a discontinuous record of vegetation variability in time and space.A first examination of the pollen diagrams reveals a high regional variability controlled by local conditions, and throughout the interval a southward increase in herb pollen frequency in contrast to the tree pollen frequency. This indicates that open and probably dry environments existed in the southern Mediterranean region prior to, during and after the salinity crisis. Trees developed in areas close to mountains such as in the Po Valley, in Cerdanya and in the Black Sea region. Most variations observed in the pollen diagrams are constrained by fluctuations of Pinus pollen amounts, indicating eustatic variations. Climatic quantification from pollen data does not show obvious climatic changes due to the desiccation of the Mediterranean Sea, especially in the dry and warm southwestern Mediterranean area (Sicily, southern Spain and North Africa). At Maccarone, along the Adriatic Sea, a decrease in temperatures of the coldest month and, less importantly, a decrease in mean annual temperatures, corresponding to a drastic vegetation change, are reconstructed. These temperature variations are assumed to be controlled by regional environmental changes (massive arrival of waters in this basin) rather than to reflect cooling, because some authors link the second phase of evaporite deposition to a period of global warming. Some migrations of plants probably occurred as a response to Mediterranean desiccation. But the climatic contrast which has probably existed at that time between the central Mediterranean and the peripheral areas might be amplified.Climatic reconstruction from pollen data in the western Mediterranean area shows that climate is not the direct cause of the Mediterranean desiccation, as the Mediterranean region had experienced continuously high evaporation long before the crisis. Therefore the main factor leading to this event seems to be the successive closures of the Betic and Rifian corridors, isolating the Mediterranean Sea from the Atlantic Ocean

Exhumation of Messinian evaporites in the deep-sea and creation of deep anoxic brine-filled collapsed basins, 2006, Cita Mb,
The first part of the paper summarizes some basic concepts concerning (a) the distribution of Messinian evaporites in the deepest parts of the Mediterranean Sea and (b) the Mediterranean Ridge accretionary wedge and its peculiar characteristics deriving from the presence of a substantial evaporitic body in the deforming sedimentary prism.Then five brine-filled anoxic collapsed basins (Tyro, Bannock, Urania, Atalante and Discovery), discovered from 1983 to 1994, are presented and discussed in their physiographic, geologic, hydrologic and geochemical characters. High density brines deriving from submarine dissolution of outcropping or subcropping evaporites accumulate at the bottom of collapsed basins, if they are not swept away by submarine currents. The interface separating normal sea-water from high density brines is sharp with a density contrast of about 20% and lies at 3200-3500[no-break space]m below sea level. Strong bacterial activity is developing at the interface and living bacteria have been recovered from the anoxic salty brines. Thickness of the brines may be up to 500[no-break space]m. Thermal stratification has been observed in three brine lakes. Exhumation and dissolution of Messinian evaporites in the Mediterranean Ridge occur in different tectonic settings: pull-apart basin (Tyro), subducting seamount close to the outer deformation front (Bannock Basin), top of a backstop (Urania, Atalante and Discovery Basins).Chemistry of the brines is strongly variable and suggests dissolution of different layers or levels of the Messinian suite. Discovery brines are the saltiest ever recorded in natural environment. Their saturation in Mg chloride (bischofite), the end product of sea-water evaporation, suggests that the deepest parts of the eastern Mediterranean were close to dryness at the end of the salinity crisis, strongly supporting the deep basin desiccation model

Geodynamic evolution of the peri-Mediterranean karst during the Messinian and the Pliocene: evidence from the Ardeche and Rhone Valley systems canyons, Southern France, 2006, Mocochain Ludovic, Clauzon Georges, Bigot Jean Yves, Brunet Philippe,
During the Messinian-Pliocene eustatic cycle, the Mediterranean Sea was characterized by a short lived (5.95-5.32[no-break space]Ma) sea-level fall, which attained - 1500[no-break space]m in some areas. The study of benchmark levels permits the chronology and dynamics of this event to be established. In the Rhone's middle valley, our investigations allow a new interpretation for the genesis of the Ardeche endokarst. A fall in base-level was responsible for both the incision of the so-called Messinian canyons as well as a deep karst development. Karst systems were formed in association with the Messinian canyons of the Ardeche and Rhone Rivers. During the flooding of the Mediterranean Basin (5.32[no-break space]Ma), these karst systems were filled by water and plugged by sedimentary infilling of the rias. This mechanism pushed groundwater backward through the karst system, which in turn formed diagnostic 'chimney-shafts'. These pathways were geometrically connected to the position of the Pliocene benchmark levels. Consequently, the Messinian Salinity Crisis was responsible for two karst responses.The first was concomitant with the crisis itself and corresponds to the formation of a karst system. The second followed the Messinian Salinity Crisis and corresponds to the adaptation of this karst system in Vauclusian karsts by the formation of 'chimney-shafts'

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