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Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

Did you know?

That soilwater zone is the upper portion of the zone of aeration containing soil water [16].?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
Engineering challenges in Karst, Stevanović, Zoran; Milanović, Petar
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Featured articles from other Geoscience Journals
Geochemical and mineralogical fingerprints to distinguish the exploited ferruginous mineralisations of Grotta della Monaca (Calabria, Italy), Dimuccio, L.A.; Rodrigues, N.; Larocca, F.; Pratas, J.; Amado, A.M.; Batista de Carvalho, L.A.
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
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Your search for adriatic sea (Keyword) returned 22 results for the whole karstbase:
Showing 1 to 15 of 22
General characteristics of the landforms in the Alps and Julian Prealps and in Trieste Karst., 1989, Vaia Franco
The morphology of the Julian Alps and Prealps and of the Triestian Karst are here shortly described; the structures, which defined its origin and development, are also considered. We can notice some cliffs which follow one another from the State boundary to the Adriatic sea; they are made up by lithologic successions, which repeat themselves according to the latitude. Anyway we recognize a general outcropping of rock masses which are decreasing little by little southward as regards the altitude, the age and than the erodibility. There are some differences between the western (Carnian) and the eastern (Julian) bend of the regional mounts according not only to the latitude but to the longitude, because of the lithology. In fact, the Julian mountains often look like the Dolomities in the northern zone. The southern ones, particularly near the high alluvial plain, are rounded and gently dipping. The drainage networks are quite different too. In the upper zone it is a trellis net, in the lower one is locally a trellis net and than it becomes a dendritic system. The glacial erosion follows the same principle too, coming southward along the main and the subordined valley cuts. At last, the Karst morphology shows itself strongly conditioned by the structural scheme as well as by the lateral lithologic changes. It comes out an anisotropic whole of surface forms and of subsurface ones, clearly referred to those reasons. The whole area here described shows moreover a high evolutive dynamics, connected with the recent tectonic phases.

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.

THE VRANA LAKE HYDROLOGY (ISLAND OF CRES - CROATIA), 1993, Bonacci O,
The Vrana Lake on the island of Cres in the Adriatic Sea represents a specific phenomenon of karst hydrology. The island of Cres covers an area of 404.3 km2 with an average volume, of 220 x 10(6) m3 of fresh water in the lake. The island has an average rainfall of 1,063 mm, with a Mediterranean climate. The lake has a bottom reaching a depth of 62 m below mean sea level. The average water level is 14 m above mean sea level. The most probable theories on the origin of the lake and its hydrologic-hydrogeologic functioning state that it is a flooded polje in karst. The water budget method was used to define the lake catchment area at approximately 25 km2. During the last six years, there has been drastic decrease of about 3 m in the lake's water level. This phenomenon was analyzed and it was calculated that 53 percent of the water-level decline was caused by water discharges from the lake to satisfy water supply demands, and 47 percent was due to a period of low precipitation during the analyzed period

VARIOUS APPROACHES FOR FLOW SIMULATIONS IN A KARST - APPLICATION TO ROSPO MARE FIELD (ITALY), 1994, Corre B,
Rospo Mare field is located in the Adriatic Sea, 20 km of the Abruzzes coast, at an average depth of 80 m. The reservoir is a karst which is essentially conductive; yet unlike a conventional porous medium, it cannot be simulated by the usual tools and techniques of reservoir simulation. Therefore, several approaches were used to describe the flow mechanism during the production period in greater detail. The first approach consisted of generating three-dimensional images which were constrained by both petrophysical and geological factors and then, using up-scaling techniques, obtaining the equivalent permeabilities (scalar or tensorial) of grid blocks located in different zones within the karst. This approach shows that within the infiltration zone it is possible, whatever the scale, to find an equivalent homogeneous porous medium; on the other hand, within the epikarst this equivalent medium does not exist below pluridecametric dimensions. Thus it is impossible to study the sweeping mechanism on a small scale, so we must use a deterministic model which describes the network of pipes in the compact matrix, in which a waterflood is simulated by means of a conform finite-element model. This constituted the second approach. The third and final approach consisted of inventing a system of equations to analytically solve the pressure field in a network of vertical pipes which are intersected by a production drain and submitted to a strong bottom water-drive. This model allows us to simulate the water-oil contact rise within the reservoir and study the flows depending on the constraints applied to the production well. It appears that cross flows occur in the pipes even during the production period

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)

Some geological observations in Slovačka jama cave (-1268m) in Velebit mountain, Croatia, 1999, Lacković, Damir, Š, Mida Branislav, Horvatinč, Ić, Nada, Tibljaš, Darko

During three speleological expeditions the Slovačka jama cave has been explored to the depth of 1268m. In the cave there are several channels with phreatic forms. The highest relict phreatic channel is probably due to sinkholes formed on the karst uvala Veliki Lubenovac at the time of uvala formation. Lower, recent and subrecent, phreatic horizons at the cave bottom are probably a part of the underground route of the Lika river which sinks on the north-eastern side of Velebit mountain and flows through the mountain to the submarine springs in the Adriatic sea. Other channels are mostly shafts and channels with meandering vadose forms. 14C isotope analysis of speleothems shows that the oldest are situated in both ancient and subrecent phreatic channels, while younger ones are found in the vadose meandering channel.


Interpretation of groundwater level monitoring results in karst aquifers: examples from the Dinaric karst, 2000, Bonacci O, Rojebonacci T,
The paper presents an attempt to determine the characteristics of karst aquifers using information on groundwater lever (GWL) in natural holes and boreholes with different data quantity and time resolution of GWL measurements. In this paper the particulars of karst aquifers were analysed for four examples from the Dinaric karst. In all four study areas, aquifers are formed in bare, deep and well-developed Dinaric karst consisting of Cretaceous limestones. The first example represents a wide area of Imotsko polje in the karst. The aquifer was analysed on the basis of infrequent water level monitoring in natural karst water features (jamas, lakes, wells) and discharges of springs and rivers. The karst aquifer in this example is complex, non-homogenous and variable in space and time, which is frequent in the Dinaric karst. Regardless of the aforementioned it was possible to determine its elementary characteristics. The second example represents 10 wells used for the water supply for the city of Pula. The GWL and salinity were measured once a week in the period between 1981 and 1996. Even though these measurements were relatively infrequent in space and time, they served as bases for assessment of average and maximum aquifer conditions as well as boundaries of saltwater intrusion. In the third example only a portion of aquifer of the karst spring Blaz, which is in the contact with the Adriatic Seas, has been analyzed. It is a spring with an intrusion of salt water. For purposes of study of saltwater intrusion, 26 piezometers were drilled in its vicinity in which GWL, salinity and temperature were measured once a day during 168 days, a period comprising one complete cycle of seawater intrusion and retreat. These measurements proved the existence of dispersed discharge from the aquifer into the sea and its non-homogeneity in space. In the fourth example GWL was measured continuously in 10 deep (up to 300 m) piezometers in the hinterland of the Ombla Spring catchment. The measurement period lasted 2 years (January 1988 to December 1989). The analyses are made with hourly data. The results made it possible to determine numerous characteristics of the karst aquifer and a significant non-homogeneity of groundwater distribution in karst aquifers, depending more on the underground karst phenomena than the surface karst forms

Submarine karst of Croatia - evidence of former lower sea levels, 2002, Surić, Maš, A

During the last, Late Pleistocene-Holocene transgression, rising sea flooded a vast part of the Dinaric karst. Due to prevalence of carbonate rocks in the drainage area of most of the rivers on Eastern Adriatic coast, those rivers carry only approximately 20% of particulates as suspended matter and the rest is dissolved. Consequently, many typical karst features such as karrens, dolines, poljes, caves, pits and river valleys and canyons as well, presently under the sea, can still be recognized. Beside these simply drowned features, some new ones were formed by the sea level rise. Those are submarine springs, so called vruljas, brackish coastal springs and marine lakes. The most significant evidences of former subaerial conditions are speleothems in submerged caves and calc tufa deposits of drowned paleo rivers. Both of them could be used for determination of the former low sea level stands.


The origine and evolution of coastal and submarine springs in Bakar Bay, 2003, Benac Č, Edomir, Rubinić, Josip, Ož, Anić, Nevenka

The paper presents coastal and submarine springs in Bakar Bay. The northeastern coast of Bakar Bay is abound in springs, since there is the lowest placed contact between large karst aquifer and flysch lithogenetic complex which forms hydrogeological barrier. Studied area is situated between rno and Žminjca locations, where water flows out in series of concentrated coastal and submarine springs as well as on the places of a diffuse outflow. A rapid raise of sea-level from the end of the Pleistocene changed the hydrogeological conditions so that coastal springs were submerged and new ones, at higher levels appeared. Some of submerged springs continued to throw out water, that is, they started to function as submarine springs (vrulja) due to a strong inflow from the background and high pressures. Some of them were not registered, although according to water balance analyses of wider area, widespread evidences of groundwater outflow could be expected. Their position reflects geological fabric of the area. Groundwaters have intensive flowing gradient. Their flowing out in hydraulically unstable zone have facilitated mixing of sea- water and fresh-water and as a result spring-water is usually brackish.


Comparison of 14C and 230Th/234U dating of speleothems from submarine caves in the Adriatic Sea (Croatia), 2004, Surić, Maš, A, Jurač, Ić, Mladen, Horvatinč, Ić, Nada

Among the 16 speleothems that were collected from 7 submarine caves and pits for the purpose of 14C and U-Th dating and reconstructing sea-level changes, two speleothems were dated by both methods. Different environmental conditions during the speleothem deposition and after the submergence resulted with different appropriateness for speleothem dating by these techniques. Well preserved speleothems gave reliable results by both methods, while U-Th method showed disadvantage in the case of carbonates contaminated with detrital material, as well as in the case of carbonate from marine overgrowth that covers the speleothems. However, U-Th method using MC ICPMS technique which requires only 100-300 mg of sample per analysis (instead of ca. 30 g for 14C conventional method), offers better age resolution that is essential for speleothem dating.


Late Pleistocene-Holocene sea-level rise and the pattern of coastal karst inundation: records from submerged speleothems along the Eastern Adriatic Coast (Croatia), 2005, Suric Masa, Juracic Mladen, Horvatincic Nada, Krajcar Bronic Ines,
In order to reconstruct the late Pleistocene-Holocene sea-level rise along the Eastern Adriatic Coast, eight speleothems were collected from three submerged caves along the Croatian coast from depths of -38.5 to -17 m. The marine biogenic overgrowth layer and the youngest and the oldest parts of the speleothems were dated by the 14C method. Their stable isotope (13C/12C and 18O/16O) contents were also measured. From the measured 14C activity of the marine overgrowth and using the model of Alessio et al. (1992, Risultati preliminari relativi alla datazione di speleotemi sommersi nelle fasce costiere del Tirreno centrale. Giornale di Geologia ser. 3 54/2, 165-193), the start of overgrowth (i.e., the time of flooding by seawater) was determined to be 10,185 cal BP at -36 m, 9160 cal BP at -34 m, and 7920 cal BP at -23 m.Our results partially match the sea-level curves reconstructed for adjacent areas (Tyrrhenian Coast and French Mediterranean Coast). However, the start of the marine overgrowth on speleothems in pit caves indicates strong dependence on the steepness of the terrain. On steep, extensively karstified coasts, marine overgrowths on speleothems coincided with the submersion of the speleothems due to the relatively short distance between the pit and the open sea and fast penetration of seawater into the pit. In contrast, marine overgrowths on speleothems in pits in the flat terrains occurred later because speleothem growth ceased due to flooding with fresh groundwater. Later, the fresh water was replaced by seawater due to the greater distance of the inland pits to the former coast

The influence of the geological setting on the morphogenetic evolution of the Tremiti Archipelago (Apulia, Southeastern Italy), 2005, Andriani Gk, Walsh N, Pagliarulo R,
The Tremiti Archipelago (Southern Adriatic Sea), also called Insulae Diomedae from the name of the Greek hero who first landed there, is an area of high landscape and historical value. It is severely affected by significant geomorphologic processes dominated by mass movements along the coast that constitute the most important and unpredictable natural hazard for the population and cultural heritage. Coastal erosion is favoured by the peculiar geological and structural setting, seismic activity, weathering, development of karst processes, and wave action. The present paper reports on descriptive and qualitative evaluation of the factors controlling landslides and coastline changes based on medium-term in situ observation, detailed surface surveys at selected locations since 1995, and historic and bibliographic data. The Tremiti Archipelago is part of an active seismic area characterised by a shear zone separating two segments of the Adriatic microplate that have shown different behaviour and roll back rates in the subduction underneath the Apennines since middle Pleistocene. Although coastal morphology can be basically considered to be the result of wave action, the continual action of subaerial processes contributes effectively to the mechanism of shoreline degradation. Weathering mainly affects the marly calcisiltites and calcilutites of the Cretaccio Fm. and the friable and low cemented calcarenites and biomicrites of the San Nicola Fm. The cliffs are characterised by different types of failure such as lateral spreads, secondary topples, rock falls and slides. At the Isle of San Nicola, landslides are controlled by the contrast in competence, shear strength and stiffness between the Pliocene re-crystallised dolomitic calcarenites and calcisiltites and the Miocene marly calcilutites and calcisiltites. At the Isles of San Domino and Caprara rock falls are attributed to the undercutting of waves at the base of the cliffs

Grottes et karsts dEurope centrale dans les Encyclopdies franaises du XVIIIe sicle, 2006, Gauchon Christophe
Central European caves and karsts in French Encyclopaedias of xviiith century - The xviiith century, and especially the second half, was a time of great progress in natural history and, more particularly, in the knowledge of caves, and this interest for caves appeared in several Encyclopaedias published in that time. At the very end of xviith century, several dictionaries of History or Geography [Baudrand, Moreri] were printed in France. Their aim was to give a wide panorama of the whole human knowledge. After 1750, D. Diderot and J. dAlembert began the publishing of the great Encyclopaedia, or reasoned dictionary of sciences, arts and technology [1751-1765]. More than just a dictionary, this major opus of the Enlightenments purposed to criticize all the old knowledges, with the intention of rebuilding by the reason a new understanding of the world. As it was considered disrespectful towards church, Jesuits published another Encyclopaedia, the Dictionnaire de Trvoux . Then, at the end of xviiith century, Panckoucke published the huge Methodical Encyclopaedia , with three volumes for modern Geography and five for physical Geography . So, dozens and dozens of caves all over the world were described in these dictionaries and Encyclopaedias, and here well try to expose what is about central Europe. The articles about regional geography (Istria, Alps) were often reduced to historical relations or to very poor lists of geographical names. Before the publishing of the last Encyclopaedia of the century, travellers relations seemed unknown by the authors of the dictionaries. The methodical Encyclopaedia showed a clear progress with, for instance, two articles about Croatia: the article river Cettina described several phenomena of karstic hydrology; or the article Biocova dealt with the ice-caves of the Mont-Mossor. It seems that Dictionaries and encyclopaedias had better information about caves of France or Germany where fossilized bones had been discovered. Some caves of the Mediterranean countries were also well known, because of the mythological or biblical traditions; numerous references to Timavo spring were based only on ancient roman geographers. But what about the caves of central Europe? The cave of Retelstein in Styria and the cave of Ribar (Hungary) were described in the great Encyclopaedia, and the article Cave gave a long list in which we find a short mention of the caves of Postojna and Podpec (Slovenia). But the longest articles were about Cirknitz Lake: all the dictionaries gave a large place to this famous place for hunting, fishing and ploughing , as repeated Moreri or Baudrand who looked at this phenomenon as a wonder. In the great Encyclopaedia, the description was much more accurate and tried to explain the working of the lake in the surroundings: the sink holes and the resurgences were well identified. These accurate descriptions of Cirknitz Lake stand in strong contrast with the short mentions of Postojna, which is still supposed to be two milles long As to Recca of San Canzian, this place never appeared in French dictionaries and Encyclopaedias of the xviiith century: Skocjan seemed completely unknown But these various spots were described without any connection among them. If the authors of the Encyclopaedias wanted to break definitively with all the superstitions from old ages, they were not yet able to understand the meaning of what we call karstic landscapes . On this point, the age of Enlightenments appears as a time of transition. Now, articles about Carniole (former name for main part of Slovenia) show an interesting evolution of the authors points of view. Masson de Morvilliers in the Methodical Encyclopaedia (modern Geography) explained that this country contains many noteworthy caves . And in the volume v of physical Geography [1828], the article about Zirknitz Lake ended with this interesting remark: The whole range of surrounding mountains is composed with porous limestone in which rain and snow-melting waters enter () The whole country, from north borders of Carniola to the shores of Adriatic Sea, and from the caves of Planina to the Timavo Springs, is full with streams suddenly issued from the ground and pointing out a subterranean current, which is logically to link with the working of Zirknitz Lake. So, with the help of these Encyclopaedias, we may have a good survey of the erudite geography of Karst in xviiith century and we can understand the basis on which the knowledge would get positive progress during the xixth one.

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

SUBMERGED SPELEOTHEMS EXPECT THE UNEXPECTED. EXAMPLES FROM THE EASTERN ADRIATIC COAST (CROATIA), 2007, Surić, M. , Jalž, Ić, B. , Petricioli D.

With the intention of reconstructing Late Pleistocene – Holocene sea-level changes along the Eastern Adriatic coast, a series of speleothems were collected from several submerged caves and pits, in order to constrain periods of their deposition and ceased growth related to sea-level fluctuations. For that purpose, stalagmites provide more reliable records than stalactites, due to their successive layers deposited perpendicularly to the growth direction. Therefore, stalagmites have been collected preferably. But, two of 17 speleothems displayed unexpected interior morphology – speleothem L-1 collected at the depth of 1.5 m in Medvjeđa spilja Cave on Lošinj Island, and speleothem M-25 from Pit near Iški Mrtovnjak Islet collected at the depth of 25 m. Both of the samples were taken from the cave floor, in the growth position of the stalagmite. But the insight into the perpendicular cut with evident central tube revealed their true (stalactitic) origin and additional confirmations were obtained by longitudinal cut and U-Th and 14C dating. Just as the causes of their breakdowns were probably different, so were their falls; speleothem M 25 (together with several other speleothems around it) stuck in the marine sediment in its primary position, while L-1 turned upside-down and even continued crystallizing during the lower sea level. These events are possible in the continental caves, as well. Evidently, it is much easier to recognize and avoid these problems in air-filled caves than in the submarine ones where the speleothems are almost always covered with marine overgrowth, which disguises their outer morphology. Additionally, the bases of the stalagmites are also sometimes covered with marine sediment, which makes correct estimation rather difficult.


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