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Enviroscan Ukrainian Institute of Speleology and Karstology


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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 nothephreatic is referring to water moving slowly in cavities in the phreatic zone [25].?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms


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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 yield (Keyword) returned 178 results for the whole karstbase:
Showing 16 to 30 of 178
DIAGENESIS OF AN UPPER TRIASSIC REEF COMPLEX, WILDE-KIRCHE, NORTHERN CALCAREOUS ALPS, AUSTRIA, 1994,
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Satterley A. K. , Marshall J. D. , Fairchild I. J. ,
The Wilde Kirche reef complex (Early-Late Rhaetian) grew as an isolated carbonate structure within the shallow Kossen Basin. At the Triassic/Jurassic boundary a single brief(c. 10-50 ka) period of subaerial exposure occurred. The preserved karst profile (70 m thick) displays a vadose zone, enhanced dissolution at a possible palaeo-watertable (5-15m below the exposure surface), and a freshwater phreatic zone. Karst porosity was predominantly biomouldic. primary cavities and biomoulds were enlarged and interconnected in the freshwater phreatic zone; cavity networks developed preferentially in patch reef facies. Resubmegence of the reef complex allowed minor modification of the palaeokarst surface by sea floor dissolution and Fe-Mn crust deposition on a sediment-starved passive margin. Fibrous calcite (FC), radiaxial fibrous calcite (RFC) and fascicular optic calcite (FOC) cements preserved as low Mg calcite (LMC) are abundant in primary and karst dissolution cavities. FC cement is restricted to primary porosity, particularly as a synsedimentary cement at the windward reef margin. FC, RFC and FOC contain microdolomite inclusions and show patchy non-/bright cathodoluminescence. delta(18)O values ofnon-luminescent portions (interpreted as near original) are -1.16 to -1.82 parts per thousand (close to the inferred delta(18)O of calcite precipitated from Late Triassic sea water). delta(13)C values are constant ( to .2 parts per thousand). These observations suggest FC, RFC and FOC were originally marine high Mg calcite (HMC) precipitates, and that the bulk of porosity occlusion occurred not in the karst environment but in the marine environment during and after marine transgression. The HMC to LMC transition may have occurred in contact with meteoric water only in the case of FC cement. The most altered (brightly luminescent) portions of RFC/FOC cements yield delta(18)O = -2.44 to -5.8 parts per thousand, suggesting HMC to LMC alteration at up to 34 degrees C, in the shallow burial environment at depths of 180-250 m. Abundant equant cements with delta(18)O = -4.1 to -7.1 parts per thousand show crisp, uniform or zoned dull luminescence. They are interpreted as unaltered cements precipitated at 33-36 degrees C at 200-290 m burial depth, from marine-derived fluids under a slightly enhanced geothermal gradient. Fluids carrying the equant cements may have induced the HMC to LMC transition in the fibrous cements

Middle Holocene environmental change determined from the salt caves of Mount Sedom, Israel, 1994,
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Frumkin, A. , Carmi, I. , Zak, I. And Magaritz, M. , 1994
Paleoclimatic sequence for the Middle Holocene was constructed, based on Mount Sedom salt caves, and other evidence. Mount Sedom is a salt diapir, on the southwestern shore of the Dead Sea, which has been rising above the local base level throughout the Holocene. Allogenic karst development has kept pace with the rising, forming vadose caves. Wood fragments found embedded in flood sediments that were deposited in sub-horizontal cave passages yielded 14C ages from 7090 to 200 YBP. The paleoclimatic sequence is based on parameters that include: relative abundance of plant types or floral communities, the elevations of the corresponding relict cave passages and the ratio of their width to present passage width. Moister climatic stages are indicated by relatively abundant wood remains, by wide cave passages and by higher-level outlets, indicating high Dead Sea levels. Arid periods are marked by a scarcity of wood remains, by narrow cave passages and by low-level outlets. The results were correlated to other middle-Holocene evidence and temporal settlement changes. The Early Bronze period in Israel was the moistest period during the last 6000 years and as such it encouraged cultural development. It was followed by a considerable desiccation that caused a cultural deterioration.

RAPID ENTRENCHMENT OF STREAM PROFILES IN THE SALT CAVES OF MOUNT SEDOM, ISRAEL, 1995,
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Frumkin A, Ford Dc,
Rock salt is approximately 1000 times more soluble than limestone and thus displays high rates of geomorphic evolution. Cave stream channel profiles and downcutting rates were studied in the Mount Sedom salt diapir, Dead Sea rift valley, Israel. Although the area is very arid (mean annual rainfall approximate to 50 mm), the diapir contains extensive karst systems of Holocene age. In the standard cave profile a vertical shaft at the upstream end diverts water from a surface channel in anhydrite or elastic cap rocks into the subsurface route in the salt. Mass balance calculations in a sample cave passage yielded downcutting rates of 0.2 mm s(-1) during peak flood conditions, or about eight orders of magnitude higher than reported rates in any limestone cave streams. However, in the arid climate of Mount Sedom floods have a low recurrence interval with the consequence that long-term mean downcutting rates are lower: an average rate of 8.8 mm a(-1) was measured for the period 1986-1991 in the same sample passage. Quite independently, long-term mean rates of 6.2 mm a(-1) are deduced from C-14 ages of driftwood found in upper levels of 12 cave passages. These are at least three orders of magnitude higher than rates established for limestone caves. Salt cave passages develop in two main stages: (1) an early stage characterized by high downcutting rates into the rock salt bed, and steep passage gradients; (2) a mature stage characterized by lower downcutting rates, with establishment of a subhorizontal stream bed armoured with alluvial detritus. In this mature stage downcutting rates are controlled by the uplift rate of the Mount Sedom diapir and changes of the level of the Dead Sea. Passages may also aggrade. These fast-developing salt stream channels may serve as full-scale models for slower developing systems such as limestone canyons

Prhistoire et karst littoral : la grotte Cosquer et les calanques mar_seillaises (Bouches-du-Rhne, France), 1996,
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Collinagirard, J.
The Cosquer Cave is a French palaeolithic painted and engraved cave (27000/ 18500 BP) which is located under the sea, in the urgonian limestones of Cap Morgiou ("Massif des Calanques"; Marseille). The en trance was submerged at the end of the last glacial stage and is presently 37 m under sea level. A synthesis about the Cosquer cave environmental studies is presented here. Structural studies show that cave planimetry is determined by Cap Morgiou fracturations (mainly NW/SE and N/S vertical faults). Through archaeological studies, a concretion breaking period can be dated between 27000 and 18000 BP. Geomorphological study of the continental shelf at the foot of the Cosquer cave area shows fossils shorelines at -36 m, -50/55 m, -90 m, -100 m depth. Radiocarbon datings from shells collected in 100m sediments yielded a date of 13 250 BP. Direct scuba diving observations and submarine clive profiles sketching show several eustatic stand-still levels between -36 m and the sea surface indicating a probable tectonic stability during the last 10000 years.

Application and simplification of the SIMERO model for the Vozmediano Spring (Spain), 1996,
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Sanz E. ,
In order to explain the functioning of the Moncayo karst aquifer, the mathematical SIMERO model has been applied to the 21 years of information on the flow of the spring. The results yield the following mean values for the annual water balance: rainfall 714.2 mn; surface runoff 35.6 mm; actual evaporation 404.9 mn; recharge 273.7 mm. With the results of the recharge, the dependencies between it and the rainfall and temperature values have been calculated, obtaining a regression line. The SIMERO model has been simplified in such a way that the flow of the spring in a given month can be calculated by knowing only the precipitation and the temperature of that month and the flow of the previous month

Analysis of well hydrographs in a karst aquifer: Estimates of specific yields and continuum transmissivities, 1996,
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Shevenell L. ,
Hydrograph analysis techniques have been well developed for hydrographs obtained from streams and springs, where data are cast in terms of total discharge. The data obtained from well hydrographs provide water level versus time; hence, a method of hydrograph analysis is required for situations in which only water level data are available. It is assumed here that three segments on a recession curve from wells in a karst aquifer represent drainage from three types of storage: conduit (C), fracture (F) and matrix (M). Hydrographs from several wells in a karst aquifer are used to estimate the specific yields (S-y) associated with each portion of the aquifer (C, F, M), as well as continuum transmissivities (T). Data from three short injection tests at one well indicate continuum rat this well bore is approximately 5 m(2) day(-1), and tests at numerous other wells in the aquifer yield results between 1 and 7 m(2) day(-1). The T estimated with well hydrographs from two storms indicates a T of 9.8 m(2) day(-1). Well-developed conduit systems in which water levels in wells show a flashy response typically show S(y)s of 1 x 10(-4), 1 x 10(-3), and 3 x 10(-3) for C, F, and M, respectively. Less well-developed conduit areas show more nearly equal S(y)s (8.6 x 10(-4), 1.3 x 10(-3), 3 x 10(-3)). Areas with no evidence for the presence of conduits have only one, or in some cases two, slopes on the recession curve. In these cases, water-level responses are slow. Recession curves with a single slope represent drainage from only the lower T matrix. Those with two slopes have an additional, more rapid response segment on the recession curve which represents drainage from the higher T, lower S-y, fractures in the system

Dated co-occurrence of Homo erectus and Gigantopithecus from Tham Khuyen Cave, Vietnam, 1996,
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Ciochon R, Long Vt, Larick R, Gonzalez L, Grun R, Devos J, Yonge C, Taylor L, Yoshida H, Reagan M,
Tham Khuyen Cave (Lang Son Province, northern Vietnam) is one of the more significant sites to yield fossil vertebrates In east Asia, During the mid-1960s, excavation in a suite of deposits produced important hominoid dental remains of middle Pleistocene age, We undertake more rigorous analyses of these sediments to understand the fluvial dynamics of Pleistocene cave infilling as they determine how skeletal elements accumulate within Tham Khuyen and other east Asian sites, Uranium/thorium series analysis of speleothems brackets the Pleistocene chronology for breaching, infilling, and exhuming the regional paleokarst, Clast analysis indicates sedimentary constituents, Including hominoid teeth and cranial fragments, accumulated from very short distances and under low fluvial energy, Electron spin resonance analysis of vertebrate tooth enamel and sediments shows that the main fossil-bearing suite (S1-S3) was deposited about 475 thousand years ago, Among the hominoid teeth excavated from S1-S3, some represent Homo erectus and Gigantopithecus blacki, Criteria are defined to differentiate these teeth from more numerous Pongo pygmaeus elements, The dated cooccurrence of Homo erectus and Gigantopithecus blacki at Tham Khuyen helps to establish the long co-existence of these two species throughout east Asia during the Early and Middle Pleistocene

Principles of early development of karst conduits under natural and man-made conditions revealed by mathematical analysis of numerical models, 1996,
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Dreybrodt W,
Numerical models of the enlargement of primary fissures in limestone by calcite aggressive water show a complex behavior. If the lengths of the fractures are large and hydraulic heads are low, as is the case in nature, dissolution rates at the exit of the channel determine its development by causing a slow increase of water flow, which after a long gestation time by positive feedback accelerates dramatically within a short time span. Mathematical analysis of simplified approximations yields an analytical expression for the breakthrough time, when this happens, in excellent agreement with the results of a numerical model. This expression quantifies the geometrical, hydraulic, and chemical parameters determining such karat processes. If the lengths of the enlarging channels are small, but hydraulic heads are high, as is the case for artificial hydraulic structures such as darns, it is the widening at the entrance of the flow path which determines the enlargement of the conduit. Within the lifetime of the dam this can cause serious water losses, This can also be explained by mathematical analysis of simplified approximations which yield an analytical threshold condition from which the safety of a dam can be judged. Thus in both cases the dynamic processes of karstification are revealed to gain a deeper understanding of the early development of karst systems. As a further important result, one finds that minimum conditions, below which karstification cannot develop, do not exist

Palaeosecular variation observed in speleothems from western China and northern Spain, PhD thesis, 1996,
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Openshaw, S. J.

This study has produced records of the palaeosecular variation (PSV) of the earth's magnetic field from Speleothems from China and Spain. The ultimate aim of this project was to produce contemporaneous PSV records which would show that Speleothems accurately record ambient geomagnetic field behaviour. From Sichuan Province, China, five Speleothems were collected of which four were studied for their records of PSV. Eight Spanish Speleothems from the Cantabrian coast were collected but their weak magnetisation allowed only one record of PSV to be produced.
All speleothem sub-samples were weakly magnetised and had, on average, initial intensities of <100 x 10-8 Am2kg-1. Despite this, the majority of sub-samples were stable during stepwise alternating-field and thermal demagnetisation and each displayed a single component of magnetisation after removal of any secondary overprints. Rock magnetic experiments were hampered by low mineral concentrations but suggested that the remanences of each speleothem were carried by a mixture of multi and single-domain (titano-) magnetite and also by haematite present in significant quantities. The primary method of remanence acquisition appeared to be a depositional remanence sourced from flooding. This was corroborated by a linear relationship between sub-sample intensities and weight % acid insoluble detritus.
A selection of sub-samples from each speleothem were dated using uranium-thorium disequilibrium and alpha spectrometry. For the majority of sub-samples the low concentrations of uranium, high levels of detrital contamination and initially low chemical yields raised the associated dating inaccuracies above the quoted level for alpha spectrometry of 5-10%. Two Spanish Speleothems had high uranium concentrations and little, or no, detrital contamination. Percent age errors of these Speleothems ranged from 1 to 6%. Comprehensive experiments on the efficiencies of three electrodeposition methods were also undertaken. The most efficient method was found to be a modified version of the Hallstadius method (Hallstadius, 1984), which consistently achieved chemical yields between 40 and 90% for uranium and thorium.
In order to correct more analytically for the presence of detrital contamination, the leachate/leachate method of Schwarcz and Latham (1989) was tested. The maximum likelihood estimation data treatment technique (Ludwig and Titterington, 1994) was used to calculate dates from these analyses. Tests on Mexican speleothem SSJ2 gave excellent results allowing a revised dating scheme to be adopted. Tests on some sub-samples from Chinese Speleothems were generally unsuccessful due to analytical errors.
The isotope 210Pb was used to date the top surface of one speleothem. A constant growth rate was inferred which was significantly less than that calculated from the 230Th - 234U dating method. This was thought to be due to the former techniques inability to resolve growth rates of periods of less than 200 years.
Despite the dating errors associated with each speleothem the records of PSV compare well with each other and with contemporaneous records from China, Japan and also the UK (for the Spanish record). In addition. agreement with PSV data modelled from observatory records suggested that westward drift of the non-dipole geomagnetic field was predominant during the past 10ka.


Science Versus Grave Desecration: The Saga of Lake Hole Cave, 1997,
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Whyte, T. R. , Kimball, L. R.
In the spring of 1990, a prehistoric burial site in a small cave in Cherokee National Forest, Johnson County, Tennessee was almost completely destroyed by artifact collectors. Archaeological investigation of the disturbed deposits, conducted with the consent of the Eastern Band of Cherokee, yielded thousands of human skeletal remains, faunal remains, and artifacts. There may be hundreds of similar sites yet undiscovered within limestone and dolomite rocks of the southern Appalachian region. Efforts should be made by scientists and government agencies to discover prehistoric burial caves and to protect them, as American natives consider them sacred places.

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,
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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

The problem of modeling limestone springs: The case of Bagnara (north Apennines, Italy), 1997,
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Angelini P, Dragoni W,
The Bagnara spring (Central Italy), fed by a fractured, carbonate, and, in some areas, karstic aquifer, was examined. The available information is derived from geological mapping and daily flows over a period of 20 consecutive years. There are no data on the hydrogeological parameters nor on the aquifer hydraulic head, which is known only at the elevation of the spring. The objective of the work was to construct an appropriate mathematical model for the spring despite the scarcity of available information. The MODFLOW code was used to simulate the system following the equivalent porous media approach. The hydraulic conductivity and the specific yield equivalents were estimated by calibrating the model on the master depletion curve and taking into consideration the topographic elevation of the system's surface. The size of the protection area around the spring was investigated on the basis of the isochrons constructed from the results of the model

Protactinium-231 Dating of Carbonates by Thermal Ionization Mass Spectrometry: Implications for Quaternary Climate Change, 1997,
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Edwards Rl, Cheng H, Murrell Mt, Goldstein Sj,
Measurement of protactinium-231 ($^{231}$Pa) in carbonates by thermal ionization mass spectroscopy yields $^{231}$Pa ages that are more than 10 times more precise than those determined by decay counting. Carbonates between 10 and 250,000 years old can now be dated with $^{231}$Pa methods. Barbados corals that have identical $^{231}$Pa and thorium-230 ($^{230}$Th) ages indicate that the timing of sea level change over parts of the last glacial cycle is consistent with the predictions of the Astronomical Theory. Two Devils Hole calcite subsamples record identical $^{231}$Pa and $^{230}$Th ages, suggesting that the chronology of this climate record is accurate

Temporal variations of spring water temperatures in relation to the extents of the heat transport modes occuring in the karstified lower Gypsum-Keuper aquifer (Karnian, southern Germany)., 1997,
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Buiidscliiih J.
The importance of different heat transport modes was studied by analysis of the temporal sequences of spring water temperatures in a karstic aquifer. For the aquifer with a horizontal groundwater flow and flow velocities of more than 100 m year"SUP-1", model calculations indicate that horizontal heat transport in the aquifer occurs predominantly by convection. For vertical heat transport from the earth's surface, conduction and convection are implicated in varying degrees; in order to indicate these, the temporal series of the spring water temperatures were separated into their conductively and convectively components. Generally this can yield valuable information about the properties of thin surface-near aquifers. Thus, the quantification of a heat component transported vertically by convection into the aquifer can provide evidence of hydraulic conductivities as potential infiltration routes for contaminants.

GYPSUM KARST GEOHAZARDS IN CHINA, 1997,
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Yaoru Lu, Cooper A. H.

China has the worlds largest proven gypsum (CaSO4.2H2O) resources in the world. The gypsum ranges from pre-Cambrian to Quaternary in age and occurs in varied geological environments. The rapid dissolution rate of gypsum means that gypsum karst development can be very fast, resulting in progressively worsening geohazards. This paper reviews the characteristics of the gypsum deposits and their associated geohazards in China.Three kinds of gypsum karst are discussed. These include karst in massive thick beds of gypsum, karst in thin-bedded gypsum and compound karst in gypsum and carbonate rocks. Some site-specific problems are also examined. In the Shanxi coalfield, breccia pipes, or collapse columns, caused by the dissolution of Ordovician gypsum, penetrate the overlying Carboniferous and Permian coal-bearing sequences resulting in difficult coal mining conditions. In Guizhou Province re-activated gypsum karst is associated with leakage of water through the gypsum from a reservoir. Remedial engineering works have been carried out, but leakage still occurs. Groundwater abstraction from gypsiferous sequences is also problematical. It can yield sulphate-polluted water and cause subsidence problems both through gypsum dissolution and groundwater drawdown.


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