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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 interstitial water is water held in small wedge like interstices at grain contact [16].?

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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 palaeoclimatology (Keyword) returned 33 results for the whole karstbase:
Showing 16 to 30 of 33
Differences in the 14C age, [delta]13C and [delta]18O of Holocene tufa and speleothem in the Dinaric Karst, 2003, Horvatincic Nada, Krajcar Bronic Ines, Obelic Bogomil,
We studied Holocene speleothems and tufa samples collected in numerous caves and rivers in the Dinaric Karst of Croatia, Slovenia, Bosnia and Herzegovina, as well as Serbia and Montenegro. Differences in the formation process of tufa and speleothems are discussed in the context of their isotopic composition (14C, 13C and 18O), as well as the chemistry of surface water (rivers, lakes) and drip water (in caves). The physical and chemical parameters monitored in the surface water (tufa precipitation) and drip water (speleothem precipitation) show that more stable conditions accompany speleothem rather than tufa formation. This is particularly obvious in the water temperature variations (2-22[deg]C in surface water and 7-12[deg]C in drip water) and in saturation index variation (3-11 in surface water and 1-6 in drip water). The range of 14C ages recorded by Holocene speleothems (~12 000 yr) is wider by several thousands years than that of Holocene tufa samples (~6000 yr). [delta]13C values for tufa samples range from -12[per mille sign] to -6[per mille sign] and for speleothem samples from -12[per mille sign] to [per mille sign] reflecting higher soil carbon and/or vegetation impact on the process of tufa than on speleothem formation. The differences in [delta]18O values of tufa and speleothem samples from different areas reflect different temperature conditions and differing isotopic composition in the water. The study shows that speleothems from the Dinaric Karst can be used as global palaeoclimatic records, whereas tufa records changes in the local palaeoenvironment

A record of Pleistocene climate from a stalactite, Nerja Cave, southern Spain., 2003, Jimenez De Cisneros C. , Caballero E. , Vera J. A. , Duran J. J. , Julia R.

Mesozoic plate tectonic reconstruction of the Carpathian region, 2004, Csontos L, Voros A,
Palaeomagnetic, palaeobiogeographic and structural comparisons of different parts of the Alpine-Carpathian region suggest that four terranes comprise this area: the Alcapa, Tisza, Dacia and Adria terranes. These terranes are composed of different Mesozoic continental and oceanic fragments that were each assembled during a complex Late Jurassic-Cretaceous-Palaeogene history. Palaeomagnetic and tectonic data suggest that the Carpathians are built up by two major oroclinal bends. The Alcapa bend has the Meliata oceanic unit, correlated with the Dinaric Vardar ophiolite, in its core. It is composed of the Western Carpathians, Eastern Alps and Southern Alcapa units (Transdanubian Range, Bukk). This terrane finds its continuation in the High Karst margin of the Dinarides. Further elements of the Alcapa terrane are thought to be derived from collided microcontinents: Czorsztyn in the N and a carbonate unit (Tisza?) in the SE. The Tisza-Dacia bend has the Vardar oceanic unit in its core. It is composed of the Bihor and Getic microcontinents. This terrane finds its continuation in the Serbo-Macedonian Massif of the Balkans.The Bihor-Getic microcontinent originally laid east of the Western Carpathians and filled the present Carpathian embayment in the Late Palaeozoic-Early Mesozoic. The Vardar ocean occupied an intermediate position between the Western Carpathian-Austroalpine-Transdanubian-High Karst margin and the Bihor-Getic-Serbo-Macedonian microcontinent. The Vardar and Pindos oceans were opened in the heart of the Mediterranean-Adriatic microcontinent in the Late Permian-Middle Triassic. Vardar subducted by the end of Jurassic, causing the Bihor-Getic-Serbo-Macedonian microcontinent to collide with the internal Dinaric-Western Carpathian margin.An external Penninic-Vahic ocean tract began opening in the Early Jurassic, separating the Austroalpine-Western Carpathian microcontinent (and its fauna) from the European shelf. Further east, the Severin-Ceahlau-Magura also began opening in the Early Jurassic, but final separation of the Bihor-Getic ribbon (and its fauna) from the European shelf did not take place until the late Middle Jurassic.The Alcapa and the Tisza-Dacia were bending during the Albian-Maastrichtian. The two oroclinal bends were finally opposed and pushed into the gates of the Carpathian embayment during the Palaeogene and Neogene. At that time, the main N-S shortening in distant Alpine and Hellenic sectors was linked by a broader right-lateral shear zone along the former Vardar suture

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

Black Sea-Marmara Sea Quaternary connections: new data from the Bosphorus, Istanbul, Turkey, 2004, Kerey I. Erdal, Meric Engin, Tunoglu Cemal, Kelling Gilbert, Brenner Robert L. , Dogan A. Umran,
Previous studies concluded that the Bosphorus Strait was formed during the Quaternary by fluvial incision of a valley between the Black Sea, to the north, and the Marmara Sea in the south. Hitherto, however, few details of the evolution of this connection have been elucidated from the sediments deposited within the Bosphorus itself. We report here details of sedimentological and palaeontological evidence relating to this history, obtained from five boreholes drilled into the unconsolidated sediment fill in the north-central sector of the Bosphorus, together with nearby geophysical profiles. The Quaternary fill of this part of the Bosphorus comprises two major facies associations. Yellow arkosic sands dominate the lower Facies Association A: these are assigned a Middle to Late Pleistocene age and the contained faunas have a lagoonal to lacustrine character and a Black Sea provenance (Paratethyan affinities). The abruptly succeeding units of Facies Association B comprise fining and coarsening upwards units of coarse to fine shelly and clayey sands that alternate with shell-bearing green clays. These sediments were formed in a range of marine and coastal settings and biostratigraphic evidence and absolute dating demonstrate the Mid-Late Holocene age of this upper unit. Initially brackish faunal assemblages in this upper unit show an upward increase in marine and Mediterranean affinities. Integrating these new data with previously published observations from coeval deposits in the southern Bosphorus and Izmit Bay (NE Marmara Sea) we conclude that during the Late Pleistocene and Early Holocene a topographic barrier existed in the south-central sector of the Bosphorus, on both sides of which estuarine and lagoonal sediments accumulated, with distinctive Black Sea and Mediterranean faunas. During a significant rise in sea level, between 7000 and 5300 years ago, this barrier was finally submerged, permitting interchange of marine waters between the Mediterranean and the Black Sea and creating the present oceanographic situation. This evolution conflicts with the cataclysmic role of the Bosphorus in the early Holocene as postulated in the `Catastrophic Flood' hypothesis of Ryan et al. [Mar. Geol. 138 (1997) 119-126; Annu. Rev. Earth Planet. Sci. 31 (2003) 525-554]. It also contrasts with the history recorded from the Gulf of Izmit, where intermittent connection between these two bodies of water throughout much of the Quaternary is evident

Late Pleistocene paleoclimate in the Black Hills of South Dakota from isotope records in speleothems, 2004, Serefiddin Feride, Schwarcz Henry P. , Ford Derek C. , Baldwin Steve,
Two coeval speleothems from the Black Hills are used to investigate [delta]18O and [delta]13C variations within Reed's Cave and reconstruct climate during the Wisconsin glacial period from 82[punctuation space]000 to 24[punctuation space]000 years ago. Variation in growth rates between the two speleothems reveals a strong control of hydrology and surface vegetation on isotopic variability and response of [delta]18O to climate. High-resolution [delta]18O and [delta]13C data show that local environmental conditions can produce an offset of [delta]18O values of up to 4[per mille sign] in coeval speleothems but still reveal important climate events. The transition from warmer to cooler periods results in an increase in [delta]18O of calcite ([delta]18Oct) in sample RC2 while in sample RC20, another equilibrium deposit coeval to part of the RC2 record, [delta]18Oct is offset from RC2 by between 0 and -3.5[per mille sign], and shows much higher frequency isotopic variation. Speleothem RC2 records interglacial/glacial transitions and interstadial events that are also present in speleothems from North America and Europe. Spectral analysis of the [delta]18Oct records for both speleothems reveals periodicity at 1000 to 2000 years, similar to millennial scale variability seen in the North Atlantic sediments and the Greenland ice cores

Evolution of the Adriatic carbonate platform: Palaeogeography, main events and depositional dynamics, 2005, Vlahovic I. , Tisljar J. , Velic I. , Maticec D. ,
The Adriatic Carbonate Platform (AdCP) is one of the largest Mesozoic carbonate platforms of the Perimediterranean region. Its deposits comprise a major part of the entire carbonate succession of the Croatian Karst (External or Outer) Dinarides, which is very thick (in places more than 8000 m), and ranges in age from the Middle Permian (or even Upper Carboniferous) to the Eocene. However, only deposits ranging from the top of the Lower Jurassic (Toarcian) to the top of the Cretaceous can be attributed to the AdCP (defined as an isolated palaeogeographical entity). Although the entire carbonate succession of the Karst Dinarides was deposited within carbonate platform environments, there were different types of carbonate platforms located in different palaeogeographical settings. Carboniferous to Middle Triassic mixed siliciclastic-carbonate deposits were accumulated along the Gondwanian margin, on a spacious epeiric carbonate platform. After tectonic activity, culminating by regional Middle Triassic volcanism recorded throughout Adria (the African promontory), a huge isolated carbonate Southern Tethyan Megaplatform (abbreviated as STM) was formed, with the area of the future AdCP located in its inner part. Tectonic disintegration of the Megaplatform during the middle to late Early Jurassic resulted in the establishment of several carbonate platforms (including the Adriatic, Apenninic and Apulian) separated by newly drowned deeper marine areas (including the Adriatic Basin as a connection between the Ionian and Belluno basins, Lagonero, Basin, and the area of the Slovenian and Bosnian troughs). The AdCP was characterised by predominantly shallow-marine deposition, although short or long periods of emergence were numerous, as a consequence of the interaction of synsedimentary tectonics and eustatic changes. Also, several events of temporary platform drowning were recorded, especially in the Late Cretaceous, when synsedimentary tectonics became stronger, leading up to the final disintegration of the AdCP. The thickness of deposits formed during the 125 My of the AdCP's existence is variable (between 3500 and 5000 m). The end of AdCP deposition was marked by regional emergence between the Cretaceous and the Palaeogene. Deposition during the Palaeogene was mainly controlled by intense synsedimentary tectonic deformation of the former platform area-some carbonates (mostly Eocene in age) were deposited on irregular ramp type carbonate platforms surrounding newly formed flysch basins, and the final uplift of the Dinarides reached its maximum in the Oligocene/Miocene. The Adriatic Carbonate Platform represents a part (although a relatively large and well-preserved one) of the broader shallow-water carbonate platform that extended from NE Italy to Turkey (although its continuity is somewhat debatable in the area near Albanian/Greece boundary). This large carbonate body, which was deformed mostly in the Cenozoic (including a significant reduction of its width), needs a specific name, and the Central Mediterranean Carbonate Platform is proposed (abbreviated to CMCP), although the local names (such as AdCP for its NW part) should be kept to enable easier communication, and to facilitate description of local differences in platform evolution,

U-series dating and taphonomy of Quaternary vertebrates from Brazilian caves, 2006, Auler As, Pilo Lb, Smart Pl, Wang X, Hoffmann D, Richards Da, Edwards Rl, Neves Wa, Cheng H,
The geochronology and taphonomy of internationally important fossil bearing cave deposits were studied, both in the semi-arid Northern Bahia area and the subtropical southeastern Lagoa Santa area of Brazil. Taphonomic analysis suggests that the processes responsible for bone accumulation in the Brazilian caves vary between sites, and taphonomic bias can therefore be significant in causing differences in faunal composition. In the Toca da Boa Vista caves the presence of single articulated skeletons, and the entrance-related distribution indicate that random penetration of animals is the main mechanism of fossil accumulation, a process that biases the assemblage to smaller species, and takes place over extended time periods. In nearby Toca dos Ossos cave transport by runoff in the cave river is predominant, and biases the fauna remains to larger more robust bones and species. Deposition probably also occurred only at times of enhanced runoff giving a more contemporaneous assemblage. Similar processes were responsible for emplacement of the copious fossil remains in the more humid Lagoa Santa area, where terrigenous fossil deposits are found intercalated by massive speleothem calcite layers. In this area runoff under a drier climate probably accounts for the sediment emplacement inside caves. In both areas the mode of emplacement implies bias in the fossil record, resulting in fossil assemblages that do not mirror surface faunas, limiting palaeoenvironmental reconstruction.Mass spectrometric U-series analysis of speleothem calcite overlaying fossil remains gives minimum ages for fossil deposition. These ages confirm the previous view that many of the deposits derive from the late glacial, but also show that much older material (some > 350,000[no-break space]yr) is also present. The habitat requirements of critical fossil species such as bats and monkeys strongly suggest that they derive from much wetter periods when forest cover was present in the currently semi-arid Northern Bahia area. Taphonomy exerts a major control on the diversity and mode of emplacement of cave fossil deposits in eastern Brazil and thus detailed sedimentological and hydrological studies coupled with a sound geochronological approach are essential in quantifying the relative importance of each taphonomic processes before faunal and palaeoecological interpretations can be attempted

New palaeontological assemblage, sedimentological and chronological data from the Pleistocene Ma U'Oi cave (northern Vietnam), 2006, Bacon Am, Demeter F, Rousse S, Long Vt, Duringer P, Antoine Po, Thuy Nk, Mai Bt, Huong Ntm, Dodo Y,
This paper describes recent material gathered during the second fieldwork at Ma U'Oi in November 2002 by a Vietnamese-French-Japanese team. The Ma U'Oi cave, located in the province of Hoa Binh (60 km SW from Hanoi), northern Vietnam, belongs to a karstic network developed in Triassic dark-grey limestones.The cave is filled with coarse-grained breccias containing numerous fossil remains, partially preserved at several loci inside the cave (wall, vault and ground). We describe new teeth which confirm the occurrence of mammal taxa already mentioned at Ma U'Oi (Bacon et al., 2004)[Bacon, A-M., Demeter, F., Schuster, M., Long, V.T., Thuy, N.K., Antoine, P-O., Sen, S., Nga, H.H., Huong, N.T.M., 2004. The Pleistocene Ma U'Oi cave, northern Vietnam: palaeontology, sedimentology and palaeoenvironments. Geobios 37, 305-314], while others, mainly microvertebrates, emphasize the occurrence of new species for the Pleistocene of Vietnam. We report here, for the first time, the occurrence of these microvertebrates of different groups (primates, rodents, insectivores, small reptiles and amphibians) in the faunal assemblage. Among mammal taxa, the presence of one more hominid affiliated to archaic Homo is also attested by our findings. U/Th dating carried out on 2 samples extracted from breccia speleothems confirms the biochronological estimate, with fossiliferous fillings ranging from late Middle Pleistocene to Late Pleistocene

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

High resolution characterization of the Asian Monsoon between 146,000 and 99,000[no-break space]years B.P. from Dongge Cave, China and global correlation of events surrounding Termination II, 2006, Kelly Megan J. , Edwards R. Lawrence, Cheng Hai, Yuan Daoxian, Cai Yanjun, Zhang Meiliang, Lin Yushi, An Zhisheng,
Speleothem samples from Hulu (eastern China, 32[deg]30'N, 119[deg]10'E) and Dongge (southern China, 25[deg]17'N, 108[deg]5'E) Caves provide a nearly continuous record of the Asian monsoon over the last 160[no-break space]ka [Wang, Y.J., Cheng, H., Edwards, R.L., An, Z.S., Wu, J.Y., Shen, C.-C., Dorale, J.A., 2001. A high-resolution absolute-dated Late Pleistocene monsoon record from Hulu Cave, China. Science 294, 2345-2348; Yuan, D., Cheng, H., Edwards, R.L., Dykoski, C.A., Kelly, M.J., Zhang, M., Qing, J., Lin, Y., Wang, Y., Wu, J., Dorale, J.A., An, Z., Cai, Y., 2004. Timing, duration, and transitions of the last interglacial Asian Monsoon. Science 304, 575-578]. We have obtained higher resolution data in the interval between ~ 99 and 146[no-break space]ka B.P., providing a detailed account of [delta]18O variations over most of MIS 5 and the latter portion of MIS 6. Precise 230Th dating has replicated the chronology of the samples within error. The higher resolution data set confirms the timing of Asian Monsoon Termination II (the midpoint of the negative shift in [delta]18O marking the onset of the Last Interglacial Asian Monsoon), placing it at 129.0 0.9[no-break space]ka B.P. The bulk of this transition (~ 1.7[per mille sign]) took place within approximately 70[no-break space]years, with the total range of the transition being ~ 3[per mille sign]. The most abrupt portion of the shift in [delta]18O values (~ 1.1[per mille sign]) marking the end of the Last Interglacial Asian Monsoon occurred in ~ 120[no-break space]years, the midpoint of which is 120.7 1.0[no-break space]ka B.P. The Dongge Cave monsoon [delta]18O record over late MIS 6 exhibits a series of sub-orbital millennial-scale climate shifts that average 1.3[per mille sign] in magnitude and occur on average every 1.8[no-break space]ky. Abrupt shifts in [delta]18O of up to 1[per mille sign] also occurred throughout the Last Interglacial Asian Monsoon, with periods at multi-decadal to centennial timescales. Similar to the amplitude and periodicities of events found by Dykoski et al. [Dykoski, C.A., Edwards, R.L., Cheng, H., Yuan, D., Cai, Y., Zhang, M., Lin, Y., An, Z., Revenaugh, J., 2005. A high resolution, absolute-dated Holocene and deglacial Asian monsoon record from Dongge Cave, China. Earth and Planetary Science Letters 233, 71-86.] during the Holocene in the Dongge record, these shifts cover more than 1/2 of the amplitude of millennial-scale and multi-centennial-scale interstadial events during the Last Glacial Period [Wang, Y.J., Cheng, H., Edwards, R.L., An, Z.S., Wu, J.Y., Shen, C.-C., Dorale, J.A., 2001. A high-resolution absolute-dated Late Pleistocene monsoon record from Hulu Cave, China. Science 294, 2345-2348], and millennial-scale and multi-centennial-scale interstadial events during the Penultimate Glacial Period in China (this study). Abrupt decadal to millennial-scale climate events therefore appear to be a general feature of both glacial and interglacial climate. We demonstrate that monsoon intensity correlates well with atmospheric CH4 concentrations over the transition into the Bolling-Allerod, the Bolling-Allerod, and the Younger Dryas. In addition, we correlate an abrupt jump in CH4 concentration with Asian Monsoon Termination II. On the basis of this correlation, we conclude that the rise in atmospheric CO2, Antarctic warming, and the gradual portion of the rise in CH4 around Termination II occur within our 'Weak Monsoon Interval' (WMI), an extended interval of heavy [delta]18O between 135.5 1.0 and 129.0 1.0[no-break space]ka B.P., prior to Asian Monsoon Termination II and Northern Hemisphere warming. Antarctic warming over the millennia immediately preceding abrupt northern warming may result from the 'bipolar seesaw' mechanism. As such warming (albeit to a smaller extent) also preceded Asian Monsoon Termination I, the 'bipolar seesaw' mechanism may play a critical role in glacial terminations

Late Miocene and early Pliocene environments in the southwestern Black Sea region from high-resolution palynology of DSDP Site 380A (Leg 42B), 2006, Popescu Speranta Maria,
A high-resolution palynological study has been performed on late Miocene (Messinian) and early Pliocene (Zanclean) sediments cored at DSDP Site 380A (Leg 42B). A late Miocene coastal vegetation has been identified in association with a delta environment. The Pliocene is characterised by competition between the two most important vegetation components, namely humid thermophilous forests and dry steppes, with changes driven by large amplitude climatic variations. These variations are linked to other European reference pollen records and to the global temperature evolution for the early Pliocene, and result in climatostratigraphic relationships at large geographic scale. An orbital tuning is proposed with respect to new data clarifying time control on the section. The Black Sea appears to have dried up in response to the Messinian salinity crisis in the Mediterranean with which it might have been connected during periods of high sea level

The Messinian salinity crisis: Looking for a new paradigm?, 2006, Roveri M. , Manzi V. ,
The importance of the sedimentary record of Messinian events in the Apennines foredeep is due to its geological and structural settings, which allow the reconstruction of the relationships between marginal and basinal settings and provide fundamental insights into some important issues. A geologic-stratigraphic model of the Messinian Apennine foredeep indicating a possible solution for closing the last `Messinian gap' is here presented. Moreover, the establishment of a preliminary high-resolution stratigraphy for the terminal Lago Mare stage allows us to attempt Mediterranean-scale correlations across different structural settings.The Messinian evolution of the Apennine foredeep and some considerations of adjacent areas suggest the great importance of tectonic deformation in controlling Messinian events. The intra-Messinian unconformity is a common feature of the marginal basins of the Mediterranean, and it is associated in many cases to the collapse and resedimentation of primary evaporites. The genesis of such unconformity seems to be strictly related to a general tectonic reorganization of the Mediterranean area. Preliminary observation on the stratigraphy of the Lago Mare stage suggest that the high-frequency lithological cyclicity observed in the non-marine deposits of this stage, as well as the superimposed transgressive trend, are common to many Mediterranean basins. These characteristic features might reflect the interplay between a longer-term tectonic trend and higher-frequency, precession-related, climatic changes; this could represent a fundamental tool for establishing a high-resolution stratigraphic framework of the latest Messinian allowing long-distance correlations between terrestrial and marine ecosystems and hence more accurate palaeoenvironmental studies

A 164 ka record of environmental change in the American Southwest from a Carlsbad Cavern speleothem , 2006, Brook George A. , Ellwood Brooks B. , Railsback L. Bruce, Cowart James B.

A horizontal core 2.8 m in length drilled from the Georgia Giant column in Carlsbad Cavern provides climate information for the last 164 ka. Forty-six alpha spectrometric U-series ages determined at intervals of ∼7.6 cm along the core indicate five periods of deposition and five hiatuses, the longest from 136 to 110 ka. Variations in growth rate (0 to 70 mm/ka), in the abundance of aragonite, chalcedony, and Fe-bearing phases, and in 13C indicate that glacial intervals of the last 164 ka, OIS 6, 4, and 2, were much wetter than today, as were the colder substages 5d and 5b of OIS 5. By contrast, during the two warmest periods of the past 164 ka, namely OIS 5e and 1, there was no deposition on either side of the speleothem, suggesting conditions as dry or drier than today. The record from Carlsbad parallels data from many other sites in the southwestern USA and northern Mexico, and data from marine sediments and ice cores, demonstrating the extent to which ice sheet fluctuations influenced conditions in southern New Mexico. Detailed correlation of δ13C values in the Georgia Giant, which range from −6.6 to +0.9‰ relative to PDB, with distant speleothem records and with data from ice cores, further documents the linkage of southwestern climate with global-scale extent of glaciation. Values of δ18O in the Georgia Giant core range from −9.7 to −4.7‰ relative to PDB and average −6.6‰. 18O-depleted carbonate in the Georgia Giant during OIS 6, at a time when the world's oceans were enriched in 18O, suggests that precipitation during cold intervals was brought largely by Pacific air masses in fall, winter and spring as a result of the southward displacement of the polar jet stream by the growth of the Laurentide Ice Sheet. Termination II, marking the end of the penultimate glaciation, is well defined in the core's δ18O data. Analytical uncertainties in the radiometric ages do not preclude a start of Termination II as late as 128 ka, as suggested by SPECMAP data. However, data from the Georgia Giant core are more compatible with an earlier start like that obtained from Devils Hole and Vostok data, raising the possibility that early warming was widespread in the U.S. southwest region by 145 ka. 


Monitoring climatological, hydrological and geochemical parameters in the Pre Nol cave (Belgium): implication for the interpretation of speleothem isotopic and geochemical time-series, 2008, Verheyden S. , Genty D. , Deflandre G. , Quinif Y. And Keppens E.
Pre Nol cave climatology (air and water temperature, PCO2), hydrology (drip rate, conductivity) and geochemistry of water and calcite deposits (?18O, ?13C, Mg/Ca and Sr/Ca) where studied to better interpret stable isotopic and trace element variations of speleothems. Results of an automated monitoring station and of manual sampling between 1991 and 1998 have demonstrated the highly seasonal signal of drip rate, its control by water excess and rainfall, and, at a shorter scale to air pressure changes. The modern calcite deposit study suggests a relationship between cave calcite isotopic composition (?18O and ?13C) and drip rate likely due to variations in degree of isotopic equilibrium during calcite precipitation. ?18O and ?13C of the calcite are therefore, through drip rate, linked to water recharge. Mg/Ca and Sr/Ca ratios of Pre Nol cave calcite, depend closely on the residence time of the water, and therefore are also linked to drip rate and therefore to water recharge. This crossed link of ?18O and ?13C as of Mg/Ca and Sr/Ca to water recharge may explain the very similar variations of these four parameters along the longitudinal axis of a Holocene stalagmite, but it may also be the consequence of kinetic effects during calcite precipitation as suggested by similar variations of the four parameters along a single layer of the Holocene stalagmite.

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