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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. ...

Did you know?

That flow-mass curve is 1. a mass curve with runoff discharge as a hydrologic quantity [16]. 2. the integral of the curve of a hydrograph [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 paleoclimate (Keyword) returned 88 results for the whole karstbase:
Showing 31 to 45 of 88
Sediments and stratigraphy in rockshelters and caves: A personal perspective on principles and pragmatics, 2001, Farrand Wr,
Over the last half century the study of rockshelter and cave sediments has evolved from straightforward descriptive analysis to sophisticated examination on several scales-from field observations to bulk laboratory analyses to microscopic examination. Still an integrated theory to guide the interpretation of these analyses does not exist, in part because of the idiosyncratic nature of individual eaves and rockshelters. This paper reviews studies that couple field observations with laboratory analyses including particle size, pebble morphology, chemical, and mineralogical studies to provide, first, the necessary basic description of the sediments and, second, an interpretation of the environment of sedimentation. These studies can lead to an understanding of site-formation processes during human occupation, and eventually to a reconstruction of local and, in some cases, regional paleoclimates. Furthermore, sediment study is essential for intrasite correlation, independent of artifact, faunal, floral, and radiometric techniques. Finally, it is emphasized that close cooperation among sedimentologists, archaeologists, and biological specialists during planning, excavation, and interpretative stages is crucial to a successfully integrated study. (C) 2001 John Wiley & Sons, Inc

The sedimentary records in Mediterranean rockshelters and caves: Archives of environmental change, 2001, Woodward J. C. , Goldberg P. ,
It is important to develop rigorous methods and robust conceptual models for the interpretation of rockshelter and cave sediment records so that the cultural sequences they contain can be considered in their proper environmental context. Much of what we know about the prehistory of the Mediterranean region and adjacent areas has largely been pieced together from materials excavated from sedimentary sequences in these environments. The rockshelters and caves of the region form important environmental and sedimentary archives. Recent work has begun to consider if the remarkable climatic variability evident in the high resolution lacustrine and ice core records is manifest in the rockshelter and cave sediment records of the area, In this context, the two main characteristics of a rockshelter or cave site which control its usefulness as an archive of environmental change are the temporal resolution of the sedimentary record and the environmental sensitivity of the site. Many rockshelters and caves can be described as either Active Karst Settings (AKS) or Passive Karst Settings (PKS) and site type is an important influence on climatic sensitivity with a direct influence upon the usefulness of the sedimentary sequence as a proxy record of climate change. It is now clear that some sites may preserve detailed paleoclimatic records and the climatic signal may be represented by distinctive suites of micromorphological features, by variations in the input of allogenic sediment, or by fluctuations in the mineral magnetic properties of the fine sediment fraction. It can be argued that data derived from the analysis of bulk coarse-grained samples often lacks the stratigraphic resolution and environmental sensitivity that can be obtained from other approaches. The most favorable sites for detailed paleoclimatic reconstruction appear to be in active karst settings such as Theopetra Cave (Greece) and Pigeon Cave (Morocco) where micromorphological analyses offer insights into the stratigraphic record that are not otherwise obtainable. The temporal resolution of a site can only be established through a rigorous stratigraphic analysis and a comprehensive dating program. These are fundamental considerations in the study of rockshelter sediment records, especially when attempting to correlate between sites and draw comparisons with other proxy records of environmental change derived from sedimentary environments with rather different characteristics. Rockshelters and caves are part of a wider sediment system, and their investigation must be accompanied by detailed geomorphological, sedimentological, paleoecological, and geochronological studies of the off-site Quaternary record.

Geochronology of late Pleistocene to Holocene speleothemsfrom central Texas: Implications for regional paleoclimate, 2001, Musgrove Marylynn, Banner Jay L. , Mack Larry E. , Combs Deanna M. , James Eric W. , Cheng Hai, Edwards R. Lawrence,
A detailed chronology for four stalagmites from three central Texas caves separated by as much as 130 km provides a 71 000-yr record of temporal changes in hydrology and climate. Mass spectrometric 238U-230Th and 235U-231Pa analyses have yielded 53 ages. The accuracy of the ages and the closed- system behavior of the speleothems are indicated by interlaboratory comparisons, concordance of 230Th and 231Pa ages, and the result that all ages are in correct stratigraphic order. Over the past 71 000 yr, the stalagmites have similar growth histories with alternating periods of relatively rapid and slow growth. The growth rates vary over more than two orders of magnitude, and there were three periods of rapid growth: 71-60 ka, 39-33 ka, and 24-12 ka. These growth-rate shifts correspond in part with global glacial-interglacial climatic shifts. Paleontological evidence indicates that around the Last Glacial Maximum (20 ka), climate in central Texas was cooler and wetter than at present. This wetter interval corresponds with the most recent period of increased growth rates in the speleothems, which is consistent with conditions necessary for speleothem growth. The temporal shift in wetness has been proposed to result from a southward deflection of the jet steam due to the presence of a continental ice sheet in central North America. This mechanism also may have governed the two earlier intervals of fast growth in the speleothems (and inferred wetter climate). Ice volumes were lower and temperatures in central North America were higher during these two earlier glacial intervals than during the Last Glacial Maximum, however. The potential effects of temporal variations in precession of Earth's orbit on regional effective moisture may provide an additional mechanism for increased effective moisture coincident with the observed intervals of increased speleothem growth. The stalagmites all exhibit a large drop in growth rate between 15 and 12 ka, and they show very slow growth up to the present, consistent with drier climate during the Holocene. These results illustrate that speleothem growth rates can reflect the regional response of a hydrologic system to regional and global climate variability

Stable isotope stratigraphy of Holocene speleothems: examples from a cave system in Rana, northern Norway, 2001, Linge H. , Lauritzen S. E. , Lundberg J. , Berstad I. M. ,
High-precision TIMS U-series dates and continuous stable oxygen and carbon isotope profiles of a 4000 year stalagmite record from Rana, northern Norway, are presented and compared with data from two other speleothems from the same cave. The dating results yield ages from 387534 to 2963 years before AD2000, with 2[sigma] errors from 0.5 to 1%. The overall growth rate is 35 mm/ka, corresponding to a temporal resolution of 29 years/mm. The stalagmite is tested for isotopic equilibrium conditions, where all `Hendy' tests, except one, indicate isotopic equilibrium or quasi equilibrium deposition. Both the stable oxygen and carbon isotope records reveal a strong and abrupt enrichment in the near-top measurements. This corresponds in time to the opening of a second cave entrance in the late 1960s, which caused changes in the cave air circulation. The stable oxygen isotope signal is enriched compared to the modern value over the last 300 years, indicating a negative response to temperature changes. Likewise, the stable carbon isotope record is enriched in this period. However, both of the stable isotope records are shown to be significantly enriched compared to the isotope ranges displayed by other stalagmites in the same cave, and this questions the reliability of the proxy records derived from the presented stalagmite. Still, a general good correspondence of large scale fluctuations is found between the three stable oxygen isotope records from this cave. The stable carbon isotope records show large variations within the cave and are believed to be governed by soil-zone conditions, percolation pathways and possibly driprates

Radiocarbon chronology of the Holocene Dead Sea: Attempting a regional correlation, 2001, Frumkin, A. , Kadan, G. , Enzel, Y. , And Eyal, Y.

Sedimentary and geomorphic sequences from the Dead Sea region, Israel, are compared by correlation of more than 50 radiocarbon ages which provide the chronology of the region during the Holocene. The chronology allows us to detect basin-scale events which are hard to detect in single-site records. We show the possible use of such correlations for paleoclimate reconstruction, indicated by the Dead Sea level. The Holocene Dead Sea apparently reached a relatively high level at the mid-Holocene around 4400 BP and 3000 cal BCE. Around 4000 BP and 2500 cal BCE it fell sharply and later fluctuated close to early 20th century levels. The radiocarbon-based correlation is also used to estimate the rising rates of Mount Sedom salt diapir. The most probable average diapir rising rate is from 5 to 7 mm/yr.

Karst and caves of Israel, 2001, Frumkin, A.
Israel displays a gradient of karst features from the intensive karstification of Lebanon in the north to practically no karst in Elat region at the southern Negev desert (Gerson, 1976). This is attributed mainly to the climatological gradient from alpine-Mediterranean climate in the Lebanon - Hermon mountains in the north, with precipitation >1000 mm/year, to the extremely arid southern Negev, with <50 mm/year. Another factor is the southward decrease in carbonates/clastics ratio of the phanerozoic stratigraphic section, due to the increasing distance from the Tethys Sea which deposited the significant carbonates. Carbonate rocks outcrop in some 75% of the hilly regions of Israel. They are predominantly of Jurassic to Eocene age. However, much of the carbonates contain marls which inhibit extensive karst development, promoting the dominance of fluviokarst features. Another inhibiting factor is the abundance of faults in the Hermon, Galil and Shomeron regions. The faults are thought to constrain the temporal and spatial continuous underground flow, limiting the development of large caves in these regions. Most limestone caves are relict phreatic conduits and voids, which do not show any genetic relation to subaerial topography. Today these caves are either dry or experience vadose dripwater. These caves have possibly developed under moister conditions than predominate today. Some of them have been sealed from the surface until opened by recent construction activity. They may contain valuable paleoclimatic records (Frumkin, et al., 1994). Vadose caves are also common, and typically experience some water flow and active dissolution during the rainy season. These are mostly composed of vertical shafts with rare horizontal sections. The unique rock salt karst of Mount Sedom exhibits the largest salt caves known in the world. Some sea caves, attributed mainly to wave action with limited dissolution appear in the 'Kurkar' sandstone ridge along the Mediterranean coast. Paleokarst is common in the stratigraphic section, and is probably related to humid paleoclimates. Israel is especially rich in man made caves sustaining abundant fauna, but are beyond the scope of this review.

Characteristics and genetic analysis of the deep-buried weathered-crust karst hydrocarbon reservoirs of the Lower Paleozoic group in the Tarim basin, 2002, Gu J. Y. , Zhang X. Y. , Fang H. ,
The genetic analysis of the deep-buried reservoirs of the Lower Paleozoic carbonate rocks in the Tarim basin is a difficult task involving many factors. Firstly, the object of study is carbonate rocks, which have undergone a long term of modification. Secondly, the rocks are deeply buried with depths of 3800-7000 m in the Tarim basin. The primary reservoir properties formed in the deposition have been strongly modified during the deep burial process. Concurrently, the different burial depths in different areas result in diversities of burial temperature, pressure, underground water, hydrochemistry and various physicochemical changes, which further lead to differences in the diagenetic type, diagenetic property, diagenetic degree and their impacts on the reservoir properties. The Lower Paleozoic Cambrian and Ordovician carbonate reservoirs in the Tarim basin can be grouped into four types,.i.e., paleo-weathered-crust reservoirs, reef reservoirs, buried karst reservoirs and dolomite reservoirs. This paper presents a detailed discussion on the vertical and horizontal distribution characteristics, morphological division, reservoir properties and the efficiency in accumulating hydrocarbons of the paleo-weathered-crust type. Furthermore, its genesis is also analyzed. We proposed that the composition of the carbonate rocks, the tectonic movement with associated fractures and fissures, the paleomorphology and paleoclimate, the sea level fluctuation, and the protection of the pores and fissures by the deep burial diagenesis and burial dissolution are the main factors controlling the formation of the paleo-weathered-crust reservoirs. We also consider that the petroleum exploration of the Lower Paleozoic carbonate rocks should be focused on the paleo-weathered-crust reservoirs

Stalagmite growth and paleoclimate: the numerical perspective., 2003, Kaufmann G.

Paleoclimate reconstruction based on the timing of speleothem growth, oxygen and carbon isotope composition from a cave located in the 'rain shadow', Israel, 2003, Vaks, A. , Barmatthews, M. , Ayalon, A. , Schilman, B. , Gilmour, M. , Hawkesworth, C. J. , Frumkin, A. , Kaufman, A. , And Matthews, A.

High-resolution 230Th/234U ages and d18O and d13C compositions of speleothems in Ma?ale Efrayim Cave located to the east of the central mountain ridge of Israel enable us to examine the nature of the rain shadow aridity during glacial and interglacial intervals. Speleothem growth occurred during marine glacial isotopic periods, with no growth during the two last marine isotope interglacial intervals and during the peak of the Last Glacial Maximum. This contrasts with speleothem growth in caves located on the western flank of the central mountain ridge, in the Eastern Mediterranean semiarid climatic zone, which continued throughout the last 240,000 yr. Thus, during glacial periods water reached both sides of the central mountain ridge. A comparison of the present-day rain and cave water isotopic compositions and amounts at the Ma?ale Efrayim Cave site with those on the western flank shows that evaporation and higher temperatures on the eastern flank are major influences on isotopic composition and the lack of rainfall. The d18O and d13C profiles of the speleothems deposited between 67,000 and 25,000 yr B.P. match the general trends of the isotopic profiles of Soreq Cave speleothems, suggesting a similar source (eastern Mediterranean Sea) and similar climatic conditions. Thus, during glacial periods the desert boundary effectively migrated further south or east from its present-day location on the eastern flank, whereas interglacial periods appear to have been similar to the present, with the desert boundary at the same position. The decrease in overall temperature and a consequent reduction in the evaporation to precipitation ratios on the eastern flank are viewed as the major factors controlling the decay of the rain shadow effect during glacial periods.

Annual resolution analysis of a SW-France stalagmite by X-ray synchrotron microprobe analysis, 2003, Kuczumow A. , Genty D. , Chevallier P. , Nowak J. , Ro C. U. ,
A sample of stalagmite from Grotte de Villars, Dordogne, France was analyzed by the use of X-ray synchrotron microprobe in LURE, Orsay, France. Together with the signal of Ca, the main element, much weaker but clear signals of Sr, Fe, Zn and Pb were registered. The X-ray scattered radiation was applied for recognition of the annual zones in the stalagmite structure in parallel with the gray scale morphology from the optical microscope. The elemental scans were superimposed on the optical image of the sample. It was established that places corresponding to dark locations on the annual rings were narrower, composed of less porous matter and had much greater contents of iron and zinc and elevated ratio of Sr/Ca. In the supplementary electron microprobe measurements, the elevated amounts of lighter elements, Si and Mg were found in the same locations. These results will allow a very accurate study of stalagmite elemental composition which is of first importance for paleoclimatic studies from speleothems. (C) 2003 Elsevier Science B.V. All rights reserved

Paleocollapse structures as geological record for reconstruction of past karst processes during the upper miocene of Mallorca Island, 2004, Robledo Ardila P. A. , Durn J. J. , Pomar L.
Paleocollapse structures and collapse breccias are one of the major features for paleokarst analysis and paleoclimate record. These are affecting the Llucmajor and Santany carbonate platforms. These platforms, of southern and eastern Mallorca respectively, are a good example of progradation reef platform in the western Mediterranean. The Santany platform is constituted of two sedimentary units, both affected by paleocollapse structures: (1) The Reef Complex attributed to the upper Tortonian-lower Messinian; (2) Santany Limestone attributed to the Messinian. There are abundant paleocollapse outcropping in the Reef Complex and Santany Limestone units. These structures have been produced by roof collapse of caverns developed in the underlying reefal complex. According to the genetic model, the origin of same paleocollapse structures may be related to early diagenetic processes controlled by high-frequency sea-level fluctuations. During the lowstands of sea level, fresh water flow or mixing zone might have created a cave system near the water table by dissolution of aragonite in the reef front facies and coral patches existing in the lagoonal beds. During subsequent rise and highstands of sea level, inner-shelf beds overlaid the previously karstified reef-core and outer-lagoonal beds. Increase of loading by subsequent accretion of the shallow-water carbonate might have produced paleocollapse structures by gravitational collapse of cave roof. Morphometric and structural classification of paleocollapse is based on geometric and structural criteria according to the type of deformed strata and strata dip. Paleocollapse structures can be classified according to geometric section, size of the paleocave and lithification degree of the host rock when collapsed. Breccias are classified as crackle, mosaic and chaotic types. In same paleocollapse the type of breccias present a vertical and lateral gradation, from crackle in the upper part, to chaotic in the lower part of the paleocollapse. Chaotic breccias grade from matrix-free, clasts-supported breccias to matrix-supported breccias. Relationship with high frequency of sea-level fluctuation, facies architecture, classification features and products permit to enhance a general paleoclimatic framework.

The Sahara-East Mediterranean dust and climate connection revealed by strontium and uranium isotopes in a Jerusalem speleothem, 2004, Frumkin A, Stein M,
This paper explores the potential of Sr and U isotope systems in speleothems as tracers of eolian dust transport and hydrological conditions. The study focuses on a speleothem from Jerusalem spanning the past 220 kyr. This speleothem provides a precisely dated record of dust flux from the Sahara to the East Mediterranean. Enhanced dust flux and Terra Rossa soil development are reflected by elevated 87Sr/86Sr ratios in the speleothem (0.7082-0.7086), while lower 87Sr/86Sr ratios (~0.7078) indicate higher contribution of the local bedrock due to low dust flux and low soil accumulation. The strontium isotope system in the speleothem is a robust monitor of the Sahara monsoon-modulated climate, since dust uptake is related to development or reduction in vegetation cover of Sahara soil. The [234U/238U] activity ratios in the speleothem range between 1.12 and 1.0. The high activity values may indicate selective removal of 234U from the soil while the low values converge to the bedrock. The migration of 234U to the cave reflects mainly the regional hydrological conditions that are modulated by the North Atlantic-Mediterranean climate system. Thus, the speleothem provides a combined record of the monsoon-North Atlantic climatic systems. Long-term stability in glacial 87Sr/86Sr ratios (0.70830.0001 over the past 220 kyr) suggests an overall similarity in eolian dust sources, and uniformity in the synoptic conditions that dominate the dust storm tracks during glacial periods

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

PALEOCLIMATE: A Better Radiocarbon Clock, 2004, Bard E, Rostek F, Menotcombes G,

Paleoclimate information from speleothems: the present as a guide to the past, 2004, Harmon R. S. , Schwarczh. P. , Gascoynem. , Hess J. W. , Ford D. C.

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