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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 bed, river is the channel of a river covered by water [16].?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
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 strength (Keyword) returned 60 results for the whole karstbase:
Showing 1 to 15 of 60
The Strength of Bolt Belays, 1976, Childs J. J.

Bungonia Caves and Gorge, A New View of Their Geology and Geomorphology, 1979, James Julia M. , Francis G. , Jennings J. N.

Work done at Bungonia since 1972 has filled gaps in our knowledge of this area. Water tracing has proven the earlier interference that the waters of all the major caves of the Lookdown Limestone and the uvula containing College Cave go to Efflux. Geological remapping shows that faulting allows these connections all to lie in limestone and accounts for the drainage of B4-5 away from the gorge. A 45m phreatic loop identified in Odyssey Cave, exceptionally large for south-eastern Australia, is also accounted for by the geological structure. Phoenix Cave has two successive cave levels similar to those of B4-5. The perched nature of the Efflux now finds a structural control in that the Folly Point Fault has interposed impervious beds between this spring and the gorge. Further analysis of the evidence relating the age of uplift and incision in the Shoalhaven and its tributaries strengthens the case for setting these in the lower Tertiary whereas most of the caves cannot be regarded as other than young. The geological remapping can partly account for the age discrepancy between underground and surface forms found at Bungonia.


Determining Doline Origins; A Case Study, 1980, Jennings J. N. , Haosheng Bao

Cases where there is clear evidence about the origin of a doline are less frequent than those where the indications are uncertain. Three dolines above Murray Cave, Cooleman Plain, which are at first sight familiar but which in fact include both solution and collapse dolines, are examined to illustrate the strengths and limitations of different kinds of evidence for doline origin. Wherever possible, underground evidence should be sought.


Alpine karsts. Genesis of large subterranean networks. Examples : the Tennengebirge (Austria) - the Ile de Crémieu, the Chartreuse and the Vercors (France), PhD Thesis, 1993, Audra, Philippe

This work, based on the study of several underground alpine networks, aims to propose some milestone in the history of these karstic regions.

The first part of the work is made up of three regional studies.

The Tennengebirge mountains are a massif of the limestone High Alps in the region of Salzburg in Austria. A cone karst close to the base level developed in the Neogene. Streams from the Alps fed the karst, resulting in the huge horizontal networks of which the Eisriesenwelt provides evidence. During the successive phases of upthrust, the levels of karstification, whether on the surface or deeper down, settled into a tier pattern, thus descending in stages from the base level. From the Pliocene era onwards, thanks to an increase in potential, alpine shafts replace the horizontal networks. The formation of these shafts is more pronounced during glaciation. The study of the Cosa Nostra - Bergerhöhle system developing 30 km of conduits on a gradient reaching almost 1 500 m provides a fairly full view of the karstification of this massif. It includes the horizontal levels developed in the Miocene and the Plio-Pleistocene, joined together by vertical sections. The most noteworthy features of the Tennengebirge, as in the neighboring massifs, lie first and foremost in the extreme thickness of the limestone which has recorded and immunized the differents steps of karstification. Secondly, the size of the networks can be, for the most part, accounted for by the contribution of allogenous waters from the streams of the Neogene and the glaciers of the Pleistocene. Generally sudden and unexpected, these flows of water engendered heavy loads (up to 600 m), simultaneously flooding several levels. To a lesser extent, the situation is similar today.

The Ile de Cremieu is a low limestone plateau on the western edge of the Jura. Due to its location in the foothills, the lobes of the Rhône glacier have covered it up, obliterating the surface karst. However, widespread evidence of anteglacial morphologies remains : paleokarst, cone karst, polygenic surface. Because of glacial plugging, access to the underground karst is limited. The main cavity is the cave of La Balme. Its initial development dates back to an early period. The morphological study has permitted the identification of several phases which go back to the Pleistocene and which are related to the Rhône glacier. The latter brought about modifications in the base level by supplying its merging waters as well as moraine material. These variations in the base level shaped the drainage structure. The underground glacial polishes are one of the noteworthy aspects recorded.

The massives of the Moucherotte and dent de Crolles belong to the northern French Prealps. They conceal large networks, respectively the Vallier cave and the Dent de Crolles. They were formed in the early Pliocene after the final orogenic phase and are in the form of horizontal conduits. The upthrust, which brought about the embanking of the Isère valley, left them in a perched position by taking away the basin which fed them. They were later, however, able to take advantage of waters from the Isère glacier during a part of the Pleistocene. The Vallier cave contains particularly glacio-karstic sediments of the lower Pleistocene, representing unique evidence of glaciation during this period. The vertical networks were put in place at the end of the Pliocene with the increase in karstification potential ; they underwent changes in the Pleistocene due to the effect of autochton and allogenous glaciers.

The second part of the work deals in general with the various forms and processes of karstification, sometimes going beyond the Alps. The study of cave deposits is a privileged tool in the understanding and reconstruction not only of the history of the networks but also the regional environment. The dating of speleothems by the U / Th method has very ofen given an age of over 350 000 years. The age of the networks is confirmed by the use of paleomagnetism which has yielded evidence of speleothems and glacio-karstic sediments anterior to 780 000 years. Anisotropic measurements of magnetic susceptibility have been used to distinguish the putting into place of glacio-karstic deposits by decantation.

Measurements of calcite rates lead to a typology of sediments based on their nature and carbonate content (rehandled weathered rocks, fluvial sands, carbonated varves, decantation clays). Granulometry confirms this differenciation by supplying precise details of transport and sedimentation modes : suspension and abrupt precipitation of clay, suspension and slow decantation of carbonated varves, suspension and rolling together with a variable sorting of sand and gravel. Mineralogical analyses oppose two types of detrital deposits. On the one hand, the rehandling of antequaternary weathered rocks extracted by the karst as a result of scouring during environmental destabilization and on the other hand, sediments characteristic of the ice age of the Pleistocene. The latter are not highly developed and their arrival in the karst is always later. Examination of heavy minerals, the morphoscopy of quartz grains and study of micromorphologies on thin blades provide precise details of conditions of evolution. The use of these methods of investigation allows for an accurate definition of the features of the evolution of the differents types of fillings, particularly speleothems, rehandled weathered rocks as well as carbonated varves. This wealth and complexity are emphasized by a detailed study of the sedimentary sequences of the Vallier cave and of the Bergerhöhle.
Speleogenesis is approached last of all in the light of above study. Emphasis is placed on the major part played by corrosion in the temporarily phreatic zone and on its many consequences (multi-level concept, simultaneous evolution of levels, origin of deep waterlogged karsts…).
Varia tions in the base level have induced karstification in contexts in which the potential was weak. These were followed by periods of increased potential to which were added the effects of glaciation. Perched horizontal levels belong to the first stages which ended in the early Pliocene, whereas alpine shafts developed in the second context. The role of structure and the parameters governing the shape of conduits (pits, meanders, canyons) are also dealt with. The different parts of the karst are borne in mind when dealing with the strength of karstic erosion during the ice age. It notably appears that it is weak on the crests and more or less non-existent in the deep parts of the karst which are liable to flooding. Finally, a preliminary analysis of an observation of neotectonic traces is presented.


SPELEOGENESIS IN AEOLIAN CALCARENITE - A CASE-STUDY IN WESTERN VICTORIA, 1994, White S. ,
Most studies of karst landscapes and their processes have been concerned with consolidated, often well-jointed limestones. There are particular problems involved in the study of karst procesess in softer, less-compact limestones such as chalk, coral reefs, and aeolian calcarenite. Previous studies in aeolian calcarenite indicated these problems and a scheme was developed of speleogenesis in aeolian calcarenite. A study of karst processes in aeolian calcarenite at Bats Ridge in western Victoria has developed this scheme further. The karst features and processes at Bats Ridge are an integral part of the landscape of a mid-Pleistocene calcarenite dune system. The resolution of problems of the rapid subaerial speleogenesis in the area is achieved by the synthesis of the known karst features of the ridge and the geology and geomorphology of the area. Karst development on this aeolianite ridge depends on lithological conditions as well as the availability of aggressive water capable of solution. The diagenesis of the calcarenite is occurring now and must have been occurring by the mid-Pleistocene. This simultaneous lithification of the carbonate dunes into aeolian calcarenite rock and the development of solutional karst features in the dunes is the characteristic feature of the speleogenesis in this area. It is the formation of a hardened kankar layer (cap rock) in the dunes of sufficient compressive and tensile strength to support cavities, which is the result of these interrelated factors, that has strongly determined the formation of the karst features

Strengthening of soils during construction under chalk karst conditions, 1994, Zhivoderov V. ,

Mixed transport reaction control of gypsum dissolution kinetics in aqueous solutions and initiation of gypsum karst, 1997, Raines M. A. , Dewers T. A. ,
Experiments with gypsum in aqueous solutions at 25 degrees C, low ionic strengths, and a range of saturation states indicate a mixed surface reaction and diffusional transport control of gypsum dissolution kinetics. Dissolution rates were determined in a mixed flow/rotating disc reactor operating under steady-state conditions, in which polished gypsum discs were rotated at constant speed and reactant solutions were continuously fed into the reactor. Rates increase with velocity of spin under laminar conditions (low rates of spin), but increase asymptotically to a constant rate as turbulent conditions develop with increasing spin velocity, experiencing a small jump in magnitude across the laminar-turbulent transition. A Linear dependence of rates on the square root of spin velocity in the laminar regime is consistent with rates being limited by transport through a hydrodynamic boundary layer. The increase in rate with onset of turbulence accompanies a near discontinuous drop in hydrodynamic boundary layer thickness across the transition. A relative independence of rates on spinning velocity in the turbulent regime plus a nonlinear dependence of rates on saturation state are factors consistent with surface reaction control. Together these behaviors implicate a 'mixed' transport and reaction control of gypsum dissolution kinetics. A rate law which combines both kinetic mechanisms and can reproduce experimental results under laminar flow conditions is proposed as follows: R = k(t) {1 - Omega(b)() zeta [1 - (1 2(1 - Omega(b)())(1/2)]} where k(t) is the rate coefficient for transport control, and Omega(b)() is the mean ionic saturation state of the bulk fluid. The dimensionless parameter zeta(=Dm(eq)()/2 delta k() where m(eq)() = mean ionic molal equilibrium concentration, D is the diffusion coefficient through the hydrodynamic boundary layer, delta equals the boundary layer thickness and k() is the rate constant for surface reaction control) indicates which process, transport or surface reaction, dominates, and is sensitive to the hydrodynamic conditions in the reactor. For the range of conditions used in our experiments, zeta varies from about 1.4 to 4.5. Rates of gypsum dissolution were also determined in situ in a cavern system in the Permian Blaine Formation, southwestern Oklahoma. Although the flow conditions in the caverns were not determinable, there is good agreement between lab- and field-determined rates in that field rate magnitudes lie within a range of rates determined experimentally under zero to low spin velocities A numerical model coupling fluid flow and gypsum reaction in an idealized circular conduit is used to estimate the distance which undersaturated solutions will travel into small incipient conduits before saturation is achieved. Simulations of conduit wall dissolution showed-member behaviors of conduit formation and surface denudation that depend on flow boundary conditions (constant discharge or constant hydraulic gradient and initial conduit radius. Surface-control of dissolution rates. which becomes more influential with higher fluid flow velocity, has the effect that rate decrease more slowly as saturation is approached than otherwise would occur if rates were controlled by transport alone. This has the effect that reactive solutions can penetrate much farther into gypsum-bearing karst conduits than heretofore thought possible, influencing timing and mechanism of karst development as well as stability of engineered structures above karst terrain

Precipitation kinetics of calcite in the system CaCO3-H2O-CO2: The conversion to CO2 by the slow process H?->CO2? as a rate limiting step, 1997, Dreybrodt W, Eisenlohr L, Madry B, Ringer S,
Precipitation rates of CaCO3 from supersaturated solutions in the H2O - CO2 - CaCO3 system are controlled by three rate-determining processes: the kinetics of precipitation at the mineral surface, mass transport of the reaction species involved to and from the mineral surface, and the slow kinetics of the overall reaction HCO3- H --> CO2 H2O. A theoretical model by Buhmann and Dreybrodt (1985a,b) taking these processes into account predicts that, due to the slow kinetics of this reaction, precipitation rates to the surface of CaCO3 minerals depend critically on the ratio V/A of the volume V of the solution to the surface area A of the mineral in contact with it, for both laminar and turbulent flow. We have performed measurements of precipitation rates in a porous medium of sized particles of marble, limestone, and synthetic calcite, with V/A ratios ranging from 3.10(-4) to 1.2-10(-2) cm at 10 degrees C. Calcite was precipitated from supersaturated solutions with [Ca2] approximate to 4 mmol/L and an initial P-CO2 of 5.10(-3) or 1.10(-3) atm, respectively, using experimental conditions which prevented exchange of CO2 with the atmosphere, i.e., closed system. The results are in qualitative agreement with the theoretical predictions. Agreement with the observed data, however, is obtained by modifying the rate law of Plummer et al. (1978) to take into account surface-controlled inhibition effects. Experiments with supersaturated solutions containing carbonic anhydrase, an enzyme which enhances the conversion of HCO3- into CO2, yield rates increased by a factor of up to 15. This provides for the first time unambiguous experimental evidence that this reaction is rate limiting. We have also measured precipitation rates in batch experiments, stirring sized mineral particles in a solution with V/A ranging from 0.03 to 0.75 cm. These experiments also give clear evidence on the importance of the conversion of HCO3- into CO2 as rate limiting step. Taken together our experiments provide evidence that the theoretical model of Buhmann and Dreybrodt (1985a,b) can be used to predict reliable rates from the composition of CaHCO3- solutions with low ionic strength in many geologically relevant situations. Copyright (C) 1997 Elsevier Science Ltd

Variations in the discharge and organic matter content of stalagmite drip waters in Lower Cave, Bristol, 1997, Baker A, Barnes Wl, Smart Pl,
Six drip waters, which were actively depositing stalagmites in Lower Cave, Bristol, were analysed both for discharge and luminescence properties. Drip discharges were determined for two different years, and show a complex response to surface precipitation variations. Inter annual variability in drip discharge is demonstrated to be significantly higher than intra-annual variability, and discharge was demonstrated both to increase and decrease non-linearly with increased precipitation. Drip waters demonstrate a correlation between their luminescence intensity and drip discharge, with increased luminescence in winter as more organic matter is flushed through the aquifer. The strength of the relationship between luminescence intensity and discharge increases with increased discharge. The results presented here have implications for the palaeoenvironmental interpretation of annual growth laminae and the growth rates of stalagmite samples.

Kinetics and mechanisms of precipitation of calcite as affected by P-CO2 and organic ligands at 25 degrees C, 1998, Lebron I. , Suarez D. L. ,
This study was conducted to develop a model for the precipitation rate of calcite under varying CO2 partial pressures and concentrations of dissolved organic carbon (DOG). Precipitation rates of calcite were measured in solutions with supersaturation values (Omega) between 1 and 20 and in the presence of 2 m(2)L(-1) of calcite. Experiments were run at partial pressures of CO2 (P-CO2) in the range of 0.035-10 kPa and DOC concentrations in the range of 0.02-3.50 mM. The effects of these two variables were quantified separately for the precipitation mechanisms of crystal growth and heterogeneous nucleation. We found an increase in precipitation rate (at constant Omega) when P-CO2 increased. For constant Omega, we also found a linear relationship between calcite precipitation rate and activity of CaHCO3, indicating that CaHCO3 species have an active role in the mechanism of calcite precipitation. These findings suggest that the increase in the precipitation rate with higher P-CO2 levels is likely caused by the increase in the negative charge on the calcite surface together with an increase in the activity of CaHCO3 species in solution. The mechanism of inhibition of calcite crystal growth by organic ligands has been shown to be surface coating of the crystals by DOG. The amount of DOC adsorbed on the surface of the calcite crystals follows a Langmuir isotherm for all the P-CO2 levels studied; however, the amount of DOC necessary to inhibit calcite precipitation increased. With increasing P-CO2, the negative charge on the crystal increases, which affects crystal growth, but also these increases in P-CO2 cause a decrease in the solution pH and increase in the ionic strength for constant Omega. Solution pH and ionic strength affect the structure and degree of dissociation of the organic functional groups, which in turn affects the and DOC concentration on the inhibition of crystal growth and heterogeneous nucleation. The effect of P-CO2 and DOC concentration on the precipitation rate of calcite is expressed in a precipitation rate model which reflects the contributions of crystal growth and heterogeneous nucleation. Copyright (C) 1998 Elsevier Science Ltd

Speleothem-based paleoclimate record from northern Oman, 1998, Burns Sj, Matter A, Frank N, Mangini A,
U-Th age dating and stable isotope measurements of speleothems from Hoti Cave in northern Oman yield paleoclimate information from the region extending to 125 ka. The results (1) provide further confirmation of an early Holocene wet period in southern Arabia extending from some time prior to 9.7 ka and ending at 6.2 ka; (2) demonstrate a second period of wetness closely coinciding with the last interglacial period, marine isotope stage (MIS) 5e; (3) indicate that during MIS 5e, southern Arabia was considerably wetter than during the early Holocene; and (4) demonstrate that periods of increased monsoon wind strength, based on data from marine sediments, do not always coincide with evidence of greatly increased precipitation even from nearby continental areas

Processes controlling colloid composition in a fractured and karstic aquifer in eastern Tennessee, USA, 1998, Mccarthy J. F. , Shevenell L. ,
Groundwater was sampled from a number of wells along recharge pathways between fractured shale and karstic formations to evaluate the chemical and hydrologic mechanisms controlling the nature and abundance of groundwater colloids. The colloids recovered using low flow rate purging and sampling exhibited a composition and abundance consistent with lithology, flow paths, and effects of hydrology and aqueous chemistry on colloid mobilization and stability. In general, the larger-size colloids and Ca-containing colloids were more abundant in the karstic lithologies, while Na-containing colloids were more important in the shales. The composition of the colloids reflected recharge pathways from the fractured shale and dolomite formations on the ridges into the limestone in the valley floor. The Mg-colloids in the limestone reflect the possible contributions from the dolomite, while the Na, K, and Si reflect possible contributions from the shale, However, it was not possible to use the colloid composition as a signature to demonstrate colloid transport from one lithology to another. Mixing of recharge water from the shale with groundwater within the limestone formation and precipitation/dissolution reactions could account for the colloids present in the limestone without invoking transport of specific shale-derived colloids into the limestone formation. The abundance of colloids in groundwater appears to be controlled by both chemical factors affecting colloid stability, as well as physical factors related to hydrology (storm-driven recharge and water velocities). In general, colloids were more abundant in wells with low ionic strength, such as shallow wells in water table aquifers near sources of recharge at the top of the ridges, Increases in cation concentrations due to dissolution reactions along Bow paths were associated with decreases in colloid abundance. However, in spite of elevated ionic strength, colloid concentrations tended to be unexpectedly high in karstic wells that were completed in cavities or water-bearing fractures. The higher levels of colloids appear to be related to storm-driven changes in chemistry or flow rates that causes resuspension of colloids settled within cavities and fractures. Published by Elsevier Science B.V

Contribution to knowledge of gypsum karstology, PhD thesis, 1998, Calaforra Chordi, J. M.

The objective of this study was not to establish a definitive judgement regarding a topic for which very little previous information was available, but rather to open new routes for research into karst by means of a particularized analysis of some of the factors involved in the speleogenesis of gypsiferous materials. The main obstacle to the attainment of this goal has been the scientific community's lack of interest in karst in gypsum, particularly in our country, until the nineteen eighties. To overcome this neglect it was decided, in my opinion quite correctly, to extend the bounds of the study as far as possible, so that the information obtained from the contrast found between the most important worldwide zones of karst in gypsum could be applied to the gypsiferous karst in our country, and in particular, to the most significant, the karst in gypsum of Sorbas.
This is the justification for the numerous references in the text to the gypsiferous karst and cavities in gypsum that are most relevant in Spain (Sorbas, Gobantes, Vallada, Archidona, Estremera, Baena, the Ebro Basin, Estella, Beuda, Borreda, etc.) and also to the best-known gypsiferous karsts worldwide (Podolia, Secchia, Venna del Gesso Romagnolo, Sicily and New Mexico). By means of these comparisons, the initial lack of information has been overcome.
The study is based on three central tenets, which are interrelated and make up the first three chapters of this report. The first consideration was to attempt to characterize the particular typology of gypsiferous karst from the geological (both stratigraphic and structural) point of view. This chapter also provides an introduction to each of the gypsiferous karsts examined. The second chapter is dedicated to the geomorphology of gypsiferous karst, under both superficial and subterranean aspects. It is important to note that the study of a gypsiferous karst from the speleological point of view is something that may seem somewhat unusual; however, this is one of the points of principle of this paper, the attempt to recover the true meaning of a word that has historically been unfairly condemned by a large part of the Spanish scientific community. Thirdly, a detailed study has been made of the hydrochemistry of the most important gypsiferous karsts in our region, together with the presentation of a specific analytical methodology for the treatment of the hydrochemical data applicable to the gypsiferous karst.
Geological characterization of gypsum karst
In the characterization of karst in gypsum, the intention was to cover virtually all the possibilities from the stratigraphic and structural standpoints. Thus, there is a description of widely varying gypsiferous karsts, made up of Triassic to Miocene materials, some with a complex tectonic configuration and others hardly affected by folding. The gypsiferous karsts described, and their most significant geological characteristics, are as follows:
Karst in gypsum at Sorbas (Almeria): composed of Miocene gypsiferous levels with the essential characteristic of very continuous marly interstrata between the layers of gypsum, which decisively affect the speleogenesis of the area. The gypsum layers have an average thickness of about 10 m and, together with the fracturing in the zone, determine the development of the gypsiferous cavities. These are mainly selenitic gypsum - occasionally with a crystal size of over 2 m - and their texture also has a geomorphologic and hydrogeologic influence. This area is little affected by folding and so the tectonic influence of speleogenesis is reduced to the configuration of the fracturing.
The Triassic of Antequera (Malaga): this is, fundamentally, the gypsiferous outcrop at Gobantes-Meliones, originating in the Triassic and located within the well-known "Trias" of Antequera. It is made up of very chaotic gypsiferous materials containing a large quantity of heterometric blocks of varied composition; the formation may be defined as a Miocene olitostromic gypsiferous breccia that is affected by important diapiric phenomena. The presence of hypersoluble salts at depth is significant in the modification of the hydrochemical characteristics of the water and in the speleogenetic development of the karst.
The Triassic of Vallada (Valencia): Triassic materials outcrop in the Vallada area; these mainly correspond to the K5 and K4 formations of the Valencia Group, massive gypsum and gypsiferous clays. The influence of dolomitic intercalations in the sequence is crucial to the speleogenesis of the area and this, together with intense tectonic activity, has led to the development in this sector of the deepest gypsiferous cavity in the world: the "Tunel dels Sumidors". As in the above case, the presence of hypersoluble salts at depth and the varied lithology influence the variations in the hydrodynamics and hydrochemistry of the gypsiferous aquifer.
Other Spanish gypsum karsts: this heading covers a group of gypsiferous areas and cavities of significant interest from the speleogenetic standpoint. They include the area of Estremera (Madrid), with Miocene gypsiferous clays and massive gypsum arranged along a large horizontal layer; this has produced the development of the only gypsiferous cavity in Spain with maze configuration, the Pedro Fernandez cave. The study of this cave has important hydrogeological implications with respect to speleogenesis in gypsum in phreatic conditions. The Baena (Cordoba) sector, in terms of its lithology, is comparable to the "Trias de Antequera". Here, the cavities developed in gypsiferous conglomerates, following structural discontinuities have enabled contact between carbonate and gypsiferous levels, and so we may speak of a mixed karstification: a karst in calcareous rocks and gypsum. The karst of Archidona (Malaga) is similar to that of the Gobantes-Meliones group and is significant because of the geomorphologic evolution of the karst, which is related to the diapiric ascent of the area and the formation of karstic ravines. The karst in the Miocene and Oligocene gypsum of the Ebro Basin (Zaragoza), has been taken as a characteristic example of a gypsiferous karst developed under an alluvial cover, with the corresponding geomorphological implications in the evolution of the surface landforms. In the gypsiferous area of Borreda (Barcelona), the presence of anhydritic levels in the sequence might have influenced the speleogenesis of its cavities. The cavity of La Mosquera, in Beuda (Girona), developed in massive Paleogene gypsum. This is the only Spanish example of a phreatic gypsiferous cavity developed in saccaroid gypsum, which is related to the particular subterranean morphology discovered. Finally, this group includes other Spanish gypsiferous outcrops visited during the preparation of this report, the references to which may be found in the relevant chapters.
Karst in gypsum in Europe and America: In order to complete the study of karst in gypsum, and with the idea of using all the available data on the karstology of gypsiferous materials for comparative studies of data for our country, a complementary activity was to define the most significant geological characteristics of the most important gypsiferous karsts in the world. An outstanding example is the gypsiferous karst at Podolia (Ukraine), developed in microcrystalline Miocene gypsum which has undergone block tectonics related to the collapse of the Precarpatic foredeep. This gypsum provides interesting data on speleogenesis in gypsiferous materials, as its evolution is related to the confining of the only gypsiferous stratum (of 10 to 20 m depth) producing interconnected labyrinthine galleries of over 100 km in length. Another well-known karst in gypsum is the one located at "Venna del Gesso Romagnolo" (Italy), in the Bologna region, with a lithology that is very similar to that which developed at Sorbas, but with the difference that it underwent more intense tectonics with folding and fracturing of the Tertiary sediments of the Po basin. In the same Italian province, in "L'alta Val di Sec-chia", there are outcrops of karstified Triassic materials which correspond to the formation of Burano, composed of gypsum and anhydrite with hypersoluble salts at depth and very notable diapiric phenomena. The study of this area has been used for a comparative analysis - geomorphology and hydrogeochemistry - with the Spanish gypsiferous karsts developed in Triassic levels. The third Italian gypsiferous karst to be considered is the one developed in Sicily, which has extensive Messinian outcrops of microcrystalline and selenitic gypsum as well as a great variety of lithologic types within the gypsiferous sequence, which we term the "gessoso solfifera" sequence. This gypsiferous karst is especially interesting from the geomorphologic standpoint due to the great quantity and variety of present superficial karstic forms. This has also served as a guide for the study of Spanish gypsiferous karsts. Finally, considering the relation between climatology and the development of karstic forms, we have also studied the karst in gypsum in New Mexico, where there is an extensive outcrop of Permian gypsum, both micro and macrocrystalline, situated on a large platform almost unaffected by deformation, and where the conditions of aridity are very similar to those found in the gypsiferous karst of Sorbas.
Geomorphological characterization of gypsum karst
From the geomorphological standpoint, the intention is to give an overview of the great variety of karstic forms developed in gypsum, traditionally considered less important than those developed in carbonate areas. This report shows this is not the case.
The theory of Convergence of Forms has been shown to be an efficient tool for the study of the morphology of karst in gypsum. Here, its principles have been used to provide genetic explanations for various gypsiferous forms derived from carbonate studies, and for the reverse case. In fact, studying a karst in gypsum is like having available a geomorphological laboratory where not only are the processes faster but they are also applicable to the karstology of carbonate rocks.
A large number of minor karstic forms (Karren) have been identified. The most important factors conditioning their formation are the texture of the rock, climatology and the presence of overlying deposits. The first, particularly, is largely responsible for determining the abundance of certain forms with respect to others. Thus, Rillenkarren, Trittkarren and small "kamenitzas" are more frequently found in microcrystalline and sandstone gypsum (for example, karst in gypsum in Sicily (Italy) and Va-llada (Valencia, Spain). Others seem to be more exclusive to selenitic gypsum, such as exfoliation microkarren, or are closely related to the climatology of the area (Spitzkarren develops from the alteration of gypsum in semiarid conditions). Others are related either to the presence of developed soil cover (Rundkarren, using Convergence of Forms), or to their specific situation (candelas and Wallkarren around dolines and sinkholes) or to the microtexture of the gypsum and the orientation of the 010 and 111 crystalline planes and twinning planes for the development of nanokarren.
The tumuli are the most peculiar forms of the Sorbas karst in gypsum, though they have also been identified in other gypsiferous karsts (Bolonia, New Mexico, Vallada, etc.). These are subcircular domes of the most superficial layer of the gypsum. Their formation has been related to processes of precipitation-solution and of capillary movement through the gypsiferous matrix. Their extensive development is largely determined by the climatology of the area and by the structural organization. It is therefore clear that the best examples are found in the karst of Sorbas due to the abrupt changes in temperature and humidity that occur in a semiarid climate, and because of the horizontality of the gypsiferous sequence.
Karst in gypsum and its larger exokarstic forms, apart from being climatically determined, also depend on the structural state and lithological determinants of the area. Thus, it is possible to differentiate between gypsiferous karsts where the lithology, together with erosive breakup, is more important (Sorbas and New Mexico) and others where confining hydraulic conditions persist (Estremera and Podolia). In other cases, tectonics has played a significant modelling role, and there is a clear possibility of an inversion of the relief (Bolonia or Sicily) or of the effect of diapiric processes (Secchia, Vallada, Antequera). The typological diversity of the dolines is obviously also related to these premisses. Another example is the relation existing between carbonate precipitation and gypsum solution, as evidenced in contrasting examples (Bolonia versus Sorbas).
Subterranean karstic forms have been examined from a double perspective: the morphology of the passages and the mineralization within the cavities. With respect to the former, a noteworthy example is the interstratification karst of Sorbas, where subterranean channels have developed during two well-differentiated phases, the phreatic and the vadose. The first was responsible for the formation of the small proto-galleries, currently relicts that are observable as false dome channels in the bottom of the gypsiferous strata. The second, with an erosive character, enabled the breakup of the marly interstrata and the formation of the large galleries found today. Other aspects considered include the speleogenetic influence of the presence of calcareous intercalations in the gypsiferous sequence (Vallada karst), gypsiferous agglomerates (Baena karst), anhydrite (Rotgers karst), suffusion processes (Sorbas karst) and the importance of condensation.
Spelothemes in gypsiferous cavities have been approached with special concern for gypsiferous speleothemes, in particular those which, due to their genetic peculiarity or to the lack of previous knowledge about them, are most significant. Among these are gypsum balls, with phenomena of solution, detritic filling, capillarity and evaporation; gypsum hole stalagmites, where the precipitation-solution of the gypsum controlling the formation of the central orifice is related to the previous deposit of carbonate speleothemes; gypsum trays that mark the levels of maximum evaporation; gypsum dust, determined by abrupt changes in temperature and humidity in areas near the exterior of gypsiferous cavities. All of these are characteristic of, and practically exclusive to, gypsiferous karsts in semiarid ztenes such as Sorbas and New Mexico.
Karst in gypsum has been morphologically classified with reference to the previously-mentioned criteria: the presence and typology of epigean karstic forms, both macro and microform; the typology of hypogean karstic forms (passages) and the type of speleothemes within the cavities (gypsiferous or carbonate). All these variables are clearly influenced by climatology, and so a study of the geomorphology of gypsiferous karst is seen to be an efficient tool for the analysis of the paleoclimatology of an area.
Hydrogeochemical characterization of gypsum karst
The hydrogeochemical characterization of karst in gypsum was approached in two stages. The first one was intended to establish themodels to be applied to the hydrochemistry approach, while the second provided various examples of hydrochemical studies carried out in gypsiferous karsts.
The theoretical framework which has been shown to be most accurate with respect to the formulation of chemical equilibria in water related to gypsiferous karst is the Virial Theory and the Pitzer equations.
For this study, we used a simplification of these equations as far as the second virial coefficient by means of a simple, polynomial variation to obtain the equilibrium state of the water with respect to the gypsum, for an ionic strength value greater than 0.1 m and temperatures of between 0.5 and 40 "C. This was the case of the gypsiferous karsts found to be related to hypersaline water at depth (Vallada, Gobantes-Meliones, Poiano). In the remaining situations, where the ionic strength was below 0.1 m, only the theory of ionic matching was used.
The hydrochemical study of the gypsiferous karst of Gobantes-Meliones (Malaga) led to the hypothesis of the possible influence of hypersaline water on karstification in gypsum. Using theoretical examples of the mixing of water derived both from hypersaline water and from water related only to the gypsiferous karst, it was shown that above a percentage content of 0.1:0.9 of saline and sulphated water, the mixture is subsaturated with respect to gypsum and other minerals. On reaching percentages greater than 0.5:0.5, values of oversaturation are again found. This could mean that the contact between sulphated and hypersaline water is a karstification zone in gypsum at depth.
In the gypsiferous karst at Salinas-Fuente Camacho (Granada), a study has been made of the hydrochemical influence of dolomitic levels in the sequence by means of the analysis of the hydrochemical routes between hydraulically-connected points. The generic case of mass transfer in this gypsiferous aquifer implies a precipitation of calcite which is in-congruent with dolomitic solution, proving that the process of dedolomitization in gypsiferous aquifers with an abundance of dolomitic rocks can be an effective process. In situations of high salinity, with contributions of hypersaline water, the process may be inverted, such as occurs in coastal carbonate aquifers influenced by the fresh-saltwater interface.
The gypsiferous aquifer of Sorbas-Tabernas (Almeria) provides the best case of karstification in gypsum in Spain; the hydrochemical study carried out has been used as an example of karstification in gypsum completely uninfluenced by sodium-chloride facies. It is shown, from the hydrochemical similarities between the different sectors, that the uniformity of the flow from the system main spring (Los Molinos) responds to the delayed hydraulic input through the overlying post-evaporitic materials and to the pelitic intercalations of the gypsiferous sequence. The aquifer is partially semiconfined, a situation which is comparable to the onset of the karstification stage, while the area of the Sorbas karst, strictly speaking, bears no hydriaulic relation to the rest of the system, behaving like a free aquifer intrinsically related to the epikarstic zone. This fact is demonstrated by the hydrochemical differences between the main spring and those related to gypsiferous cavities.
Apart from the general study of the Sorbas-Tabemas aquifer, a study was also made of the hydrochemical-time variations within cavities, and in particular within the Cueva del Agua, where it is possible to observe particular processes affecting karstification in gypsum, such as the precipitation of carbonates on the floor of the cavity which produce, in that area, a greater solution of gypsum (the phenomenon of hyperkarstification). Furthermore, the temporal evolution of the chemistry of the cavity, along 800 m of subterranean flow through its interior, shows the existence of inertial sectors where the variations were less abrupt. Only in the case of particular sectors, related to sporadic hydriaulic contributions or to the proximity to points of access., was a notable seasonal influence detected.
A similar hydrochemical study was carried out in the karst of Vallada (Valencia), along the cavity of the Tunel dels Sumidors. The chemistry here was compared with that of the springs of Brolladors (whose water rapidly infiltrates into the cavity) and Saraella (a saline resurgence of the whole system). Unexpected increases in the ionic content of certain salts (sulphates and chlorides) were detected during periods of increased flow; these were interpreted as the effect of the recharging of the Saraella spring arising from the immediate contribution of rapidly circulating sulfated water coming from the cavity and the subsequent mobilization of interstitial water with an ionic content higher than the characteristic level of the spring.
We present as a hypothesis the idea that, in addition to the hydrogeochemical processes described that can affect the evolution of a gypsiferous karst, the processes of sulphate reduction also influence karstification in gypsum, at least during the earliest stages. Some examples such as the presence of gypsum with abundant organic matter reprecipitated into phreatic channels (Sorbas) or veins of sulphur related to gypsiferous karsts (Podolia, Sicily) lend support to this idea.
Studies of the solution-erosion of gypsum have been performed by physical methods (tablets and M.E.M.) showing that the solution-erosion of gypsum within cavities is minimal (0.03 mm/ year) compared to that existing in the exterior (0.3 mm/year). The speleogenetic effect of condensation within the cavities has also been shown, with solution-erosion rates of 0.005 mm/year to be like the equivalent surface lowering. These data correspond to the karst in gypsum at Sorbas, where, additionally, a study about the time variation of the solution-erosion was carried out. It was found that the process is not continuous but clearly sporadic. During periods of torrential rain, the solution-erosion ranges from a weight loss of 400 mg/cm2/year on the surface of the karst to 75 mg/cm2/year inside the caves, while during the rest of the year the weight loss was barely 1 mg/cm2/year. The physical methods were compared with the results obtained from chemical methods, and it was found that, in general, higher values were obtained with the former (10-20% higher when weighted for the rainfall during the measuring periods). Thus it is reasonable to consider that the erosive process is more marked than was at first assumed.
In total, three cavity tracing experiments were carried out, all with fluoresceine, two of them in Cueva del Agua in Sorbas (during periods of high and low water levels) and the other in Tunel dels Sumidors in Vallada. At the first site, the comparison of the two tracing tests reveals a differential hydrodynamic behaviour of the cavity for the two contrasting situations; periods of high water input and periods of low rainfall. This behaviour is characteristic of well developed karstic aquifers, where the hydrodynamic effect of the circulation of water through small channels or, in this case, through the gypsiferous matrix and interbedded marly layers, seems to be more important under conditions of low hydraulic input than when rainfall is abundant. The two situations tested seem to confirm that the Cueva del Agua system, an epikarstic aquifer, which is representative of karstification in gypsum, has scarce retentive power and so large volumes of precipitation are totally discharged via the spring within a few days. However, the explanation of the small but continuous flow from the base of the cavity requires the inclusion of other factors in the interpretation. In this case, the flow seems to be fairly independent of rainfall and attributable to other processes, in addition to the previously described ones, such as the retentive power of the gypsiferous matrix and the marly interstrata. These might include the high degree of condensation measured over long periods, both on the surface of the karst in gypsum and within the cavities. In the case of the Tunel dels Sumidors, a highly irregular response was found, despite the fact that the coefficient of dispersivity was found to be 0.4. This value is similar to that obtained for the karst in gypsum at Sorbas in response to low water conditions, and so, here too, one might assume the influence of greater than expected flow-retaining processes, between the entry and exit points. Doubtless the karstic system of the Tunel dels Sumidors is more complex than was initially expected and in fact, the irregularity reflected by the fluoresceine concentration curve over time implies the existence of other factors to explain the diversity of the relative maxima obtained. Firstly, the presence of numerous Triassic clay intercalations might delay the flow, in addition to retaining a certain quantity of fluoresceine by ionic exchange. There is also a possibility that the flow is dispersed through a network of small conduits and pores, due to the permeability of the gypsiferous matrix. Finally, we cannot discount the possible existence of a deep-level input which, in this case, would be responsible for the variation in the flow and the chemical composition. This set of suppositions, as a whole, would explain the fact that the response of the spring to tracing is so irregular, even though we cannot achieve a definition of the qualitative influence of each one on the hydrodynamics of the system.
In order to verify some of the above hypotheses, particularly those referring to the process of condensation within cavities, an experiment was designed, consisting of a microtracing test at some points where condensation had been detected within the Cueva del Agua at Sorbas. The test produced a range of condensation flow speed values of 0.2 to 30 cm/hour and shows that, in those sections where the presence of condensation flow is visually apparent, there is a rapid dispersion of the colourant. However, it also shows that at points where there is no apparent condensation the process also occurs, but at a lower rate of efficiency. The importance of condensation within cavities has two aspects; firstly, speleogenetic, with the development of solution forms (cupolas) and deposit forms (capillarity boxwork); and secondly, hydrogeological, as this is the reason why certain processes (strong changes in temperature and humidity, multiple routes of airflow exchange with the exterior) may in themselves constitute a hydraulic contribution, of slight importance, but sufficient to explain a large part of the base flow (0.2 - 0.8 L/s) of a whole cavity system such as the Cueva del Agua in semiarid conditions.
With the intention of completing the analyses carried out in various karsts in gypsum, instruments were installed in the Cueva del Agua at Sorbas to measure, by continuous registration, some important physico-chemical parameters that might provide additional data on the hydro-geologic behaviour of this gypsiferous karst, especially at the level of the epikarstic zone. The parameters of temperature and water conductivity were considered most important, due to their singular behaviour patterns. During the experiment there were two periods of rainfall that modified the chemistry of the cavity, one of 30 mm in two days and another of 200 mm (almost the annual total) in four days. In the second case, which was much more extreme, a very significant increase in water temperature (up to 7 °C during the initial period of high water flow) was detected, while conductivity fell. But suddenly, when the minimum conductivity was reached, the temperature dropped sharply by 6-7 °C to return to the base temperature of the cavity. Subsequently, the temperature again stabilized at about 7 °C above the data recorded during the dry period. This behaviour pattern was not detected when the rainfall was slight. The explanation for this dual behaviour observed is fundamentally based on the quantity of rainfall and on the differences between the exterior air temperature, the temperature of interstitial water and the temperature recorded in the spring during high water flow. When water temperature in the cavity during high water flow is higher than the base temperature recorded in the period immediately before, it means that the interstitial water does not mobilize. However, when at any time the two temperatures coincide, one might suppose that there might have existed a process of mobilization of the water previously resident in the rock, by a piston effect, but in the unsaturated zone. On the other hand, the temporal variations of these parameters during the months following periods of high rainfall have enabled us to detect the existence of distinct periods during the return to normal cavity conditions. By carefully examining the decrease curve of water temperature inside the cavity while conductivity regained its maximum stable value, two periods may be differentiated. The first may be termed the "inertial influence period", when the rainfall occurring removes all signs of natural variation in the cavity. Thus, the daily external influences are not clearly detectable and the curve is downward-sloping and asymptotic with no significant oscillations. In the second period, which ends with the total stabilization of the parameter at the level of the initial conditions, the asymptotic descent is seen to be affected by daily temperature variations. This is termed the "inertial recovery period", during which external variations start to have an effect on the interior of the cavity such that there is a progressive increase in the amplitude of the daily variation in water temperature, air temperature and relative humidity. This behaviour pattern of variation of these parameters during periods of high rainfall, might be extended to all karstic systems, varying only in magnitude and temporal extent.


Verification of the causes of glaciations and sea level changes using the records of calcite speleothems, 2000, Forti Paolo, Georgiev Leonid, Georgieva Desislava, Lundberg Joyce, Sanabria Michael, Shopov Yavor, Stoykova Diana, Tsankov Ludmil
The luminescence of calcite speleothems displays an exponential dependence on soil temperature unless there is a dense cover of forest over the cave to dampen it. This relationship is determined primarily by the strength of solar visible and infrared radiation. It is suggested that, as a consequence, the microzonal variations of luminescence often found in speleothems can be used as a proxy index of Solar Insolation. The luminescence solar insolation proxy record of a speleothem from Jewel Cave, South Dakota, USA, was found to display millenial and centennial cycles in the record. It exhibits a rapid increase in solar insolation at 139 5.5 kyrs. This increase precedes that suggested by the Orbital theory by about 10,000 years and is due to superimposition of the most powerful cycle in solar luminosity of 11.5 kyrs, upon the curve of orbital variations. The record from a speleothem in Duhlata Cave, Bulgaria matches that of South Dakota within the limits of dating error, indicating that both of these records (which are 10,000 km apart) measure global solar insolation controls rather than local paleotemperature variations.

A modern human humerus from the early Aurignacian of Vogelherdhohle (Stetten, Germany), 2000, Churchill Se, Smith Fh,
Implicit in much of the discussion of the cultural and population biological dynamics of modern human origins in Europe is the assumption that the Aurignacian, from its very start, was made by fully modern humans. The veracity of this assumption has been challenged in recent years by the association of Neandertal skeletal remains with a possibly Aurignacian assemblage at Vindija Cave (Croatia) and the association of Neandertals with distinctly Upper Paleolithic (but non-Aurignacian) assemblages at Arcysur-Cure and St. Cesaire (France). Ideally we need human fossil material that can be confidently assigned to the early Aurignacian to resolve this issue, yet in reality there is a paucity of well-provenanced human fossils from early Upper Paleolithic contexts. One specimen, a right humerus from the site of Vogelherd (Germany), has been argued, based on its size, robusticity, and muscularity, to possibly represent a Neandertal in an Aurignacian context. The morphological affinities of the Vogelherd humerus were explored by univariate and multivariate comparisons of humeral epiphyseal and diaphyseal shape and strength measures relative to humeri of Neandertals and Early Upper Paleolithic (later Aurignacian and Gravettian) modern humans. On the basis of diaphyseal cross-sectional geometry, deltoid tuberosity morphology, and distal epiphyseal morphology, the specimen falls clearly and consistently with European early modern humans and not with Neandertals. Along with the other Vogelherd human remains, the Vogelherd humerus represents an unequivocal association between the Aurignacian and modern human morphology in Europe. (C) 2000 Wiley-Liss, Inc

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