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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 standard deviation is a measure of variability of the square of individual deviations from their mean [16].?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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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 mexico (Keyword) returned 312 results for the whole karstbase:
Showing 301 to 312 of 312
PALEOKARST CRUST OF ORDOVICIAN LIMESTONE AND ITS CAPABILITY IN RESISTING WATER INRUSHES IN COAL MINES OF NORTH CHINA, 2013, Mou L. , Li G.

With increase in mining depth of the Carboniferous-Permian coal seams in North China, it is particularly important to study the heterogeneity of karst development in the underlying Middle Ordovician limestone and determine any impermeable strata that may prevent the pressurized karst water from bursting into coal mines. Detailed analysis of the exploratory borehole data suggests presence of a paleokarst crust at the top of Middle Ordovician Fengfeng Formation. Because of its mechanical strength and low permeability to water, the paleokarst crust can function as an additional water-resisting layer. This paper takes Sihe Mine of Shanxi Province as an example to study the geotechnical and hydrogeological characteristics of the paleokarst crust. Incorporation of this additional hydrological barrier led to more minable coal seams in the coalmine.


CONCEPTUALIZATION OF GROUNDWATER FLOW IN THE EDWARDS AQUIFER THROUGH THE KNIPPA GAP HYDROGEOLOGIC CONSTRICTION, UVALDE COUNTY, TEXAS, 2013, Adkins, J.

The Balcones Fault Zone Edwards aquifer (Edwards aquifer) is one of the major regional karst aquifers in the United States, with an average withdrawal of 950 million liters per day (L/d). This study focuses on the connection between the Uvalde pool and the San Antonio pool of the Edwards aquifer, west of the San Antonio metropolitan area in Uvalde County, Texas. This area is known as the Knippa Gap and is located north of the community of Knippa. The Knippa Gap is a major zone controlling the flow from the Uvalde pool to the San Antonio pool. The San Antonio pool is the primary source of water for the greater San Antonio water supply. The Knippa Gap is a restriction where the aquifer narrows to a width estimated to be approximately 4 km, is bounded by northeast trending faults of the Balcones Fault Zone on the north, and uplift from the Uvalde salient and igneous intrusive plugs to the south. (Green et al., 2006). The hydrogeology in the Knippa Gap has been a topic of major interest among researchers in this area for numerous years, yet the exact location, nature of boundaries, and karst hydrogeology are not well defined, and the flow through this area is in need of refinement to improve the aquifer water balance.
This study integrates recent research by other scientists with field studies conducted during the summer of 2012 as part of an M.S. thesis. This paper is limited to a discussion of the water quality as it relates to the southern flow boundary of the Knippa Gap near the Devils River Trend of the Uvalde salient. Water-quality data constrain a revised conceptual model of the flow and karstification in this critical area of recharge to the San Antonio pool, and provide specific lateral boundaries and vertical karstification zones which are being tested in the more comprehensive M.S. thesis. Although current interpretations are tentative, it appears this conceptual model will be readily convertible into a digital model that can test 2hypotheses relating a much broader suite of calibration data, including water levels, water budgets, and spring discharges.


AN EVALUATION OF AUTOMATED GIS TOOLS FOR DELINEATING KARST SINKHOLES AND CLOSED DEPRESSIONS FROM 1-METER LIDAR-DERIVED DIGITAL ELEVATION DATA, 2013, Doctor D. H. , Young J. A.

LiDAR (Light Detection and Ranging) surveys of karst terrains provide high-resolution digital elevation models (DEMs) that are particularly useful for mapping sinkholes. In this study, we used automated processing tools within ArcGIS (v. 10.0) operating on a 1.0 m resolution LiDAR DEM in order to delineate sinkholes and closed depressions in the Boyce 7.5 minute quadrangle located in the northern Shenandoah Valley of Virginia. The results derived from the use of the automated tools were then compared with depressions manually delineated by a geologist. Manual delineation of closed depressions was conducted using a combination of 1.0 m DEM hillshade, slopeshade, aerial imagery, and Topographic Position Index (TPI) rasters. The most effective means of visualizing depressions in the GIS was using an overlay of the partially transparent TPI raster atop the slopeshade raster at 1.0 m resolution. Manually identified depressions were subsequently checked using aerial imagery to screen for false positives, and targeted ground-truthing was undertaken in the field. The automated tools that were utilized include the routines in ArcHydro Tools (v. 2.0) for prescreening, evaluating, and selecting sinks and depressions as well as thresholding, grouping, and assessing depressions from the TPI raster. Results showed that the automated delineation of sinks and depressions within the ArcHydro tools was highly dependent upon pre-conditioning of the DEM to produce “hydrologically correct” surface flow routes. Using stream vectors obtained from the National Hydrologic Dataset alone to condition the flow routing was not sufficient to produce a suitable drainage network, and numerous artificial depressions were generated where roads, railways, or other manmade structures acted as flow barriers in the elevation model. Additional conditioning of the DEM with drainage paths across these barriers was required prior to automated 2delineation of sinks and depressions. In regions where the DEM had been properly conditioned, the tools for automated delineation performed reasonably well as compared to the manually delineated depressions, but generally overestimated the number of depressions thus necessitating manual filtering of the final results. Results from the TPI thresholding analysis were not dependent on DEM pre-conditioning, but the ability to extract meaningful depressions depended on careful assessment of analysis scale and TPI thresholding.


DELINEATION AND CLASSIFICATION OF KARST DEPRESSIONS USING LIDAR: FORT HOOD MILITARY INSTALLATION, TEXAS, 2013, Shaw Faulkner M. G. , Stafford K. W. , Bryant A. W.

The Fort Hood Military Installation is a karst landscape characterized by Cretaceous-age limestone plateaus and canyons in Bell and Coryell Counties, Texas. The area is located in the Lampasas Cut Plain region of the Edwards Plateau and is stratigraphically defined by exposures of the Fredericksburg Group. Spatial interpolation of 105 km2 of the Fort Hood Military Installation provided depression data that were delineated and classified using geoanalytical methods. Most of the karst features within the study area are predominantly surficial expressions of collapse features, creating windows into karst conduits with surficial exposures of epikarst spatially limited.The increasing capabilities of GIS (Geographic Information Systems) and accuracy of geographically referenced data has provided the basis for more detailed terrain analysis and modeling. Research on terrain-related surface features is highly dependent on terrain data collection and the generation of digital models. Traditional methods such as field surveying can yield accurate results; however, they are limited by time and physical constraints. Within the study area, dense vegetation and military land use preclude extensive traditional karst survey inventories. Airborne Light Detection and Ranging (LiDAR) provides an alternative for high-density and high-accuracy three-dimensional terrain point data collection. The availability of high density data makes it possible to represent terrain in great detail; however, high density data significantly increases data volume, which can impose challenges with respect to data storage, processing, and manipulation. Although LiDAR analysis can be a powerful tool, filter mechanisms must be employed to remove major natural and anthropogenic terrain modifications resulting from military use, road building and maintenance, and the natural influence of water bodies throughout the study area.


INVESTIGATIONS OF LARGE SCALE SINKHOLE COLLAPSES, LAIBIN, GUANGXI, CHINA, 2013, Gao Yongli, Luo Weiquan, Jiang Xiaozhen, Lei Mingtang, Dai Jianling

A series of sinkholes collapsed at Jili village and Shanbei village, Laibin Guangxi, China in June 2010. A large underground stream exists in the north-south transect of the study area and passes the collapse site. Preliminary investigations revealed that extremely heavy rainfall between May 31 and June 1 2010 may have triggered this collapse event. The precipitation, as high as 469.8 mm within one day, was a record high in the study area. A long period of drought in 2009 followed by extremely heavy rainfall along with cave roof collapse may have caused the collapse event on June 3 2010. The “water hammer” effect and collapse-triggered earthquakes caused severe ground failure and fractures in residential houses and Jili Dam. Several collapse events were caused by extreme weather conditions in Guangxi over the past few years. Further studies of the relationship between extreme weather events and sinkhole collapses will help minimize the damage or impact to human infrastructure by avoiding areas susceptible to collapse or by designing infrastructure to better withstand subsidence


EVAPORITE KARST IN THE PERMIAN BASIN REGION OF WEST TEXAS AND SOUTHEASTERN NEW MEXICO: THE HUMAN IMPACT , 2013, Land, Lewis

A significant minority of sinkholes in the greater Permian Basin region of west Texas and southeastern New Mexico are of human origin. These anthropogenic sinkholes are often associated with historic oil field activity, or with solution mining of Permian salt beds in the shallow subsurface. The well-known Wink Sinks in Winkler Co., Texas formed in 1980 and 2002 within the giant Hendrick oil field. The Wink Sinks were probably the result of subsurface dissolution of salt caused by fresh water leakage in improperly cased abandoned oil wells. In 2008 two catastrophic sinkhole events occurred a few months apart in northern Eddy Co., New Mexico, and a third formed a few months later in 2009 near Denver City, Texas. All three sinkholes were the result of solution mining operations for brine production from Upper Permian salt beds. The Eddy Co. sinkholes formed within the giant Empire oil and gas field, several kilometers from populated areas. In the aftermath of these events, another brine well operation was identified within the city limits of Carlsbad, New Mexico as having a similar geologic setting and pumping history. That well has been abandoned and geotechnical monitoring of the site has been continuous since 2008. Although there is no indication of imminent collapse, geophysical surveys have identified a substantial void in Permian salt beds beneath the brine well extending north and south beneath residential areas, a major highway intersection, a railroad, and an irrigation canal


HYPOGENE VS EPIGENE CAVES: THE SULFUR AND OXYGEN ISOTOPE FINGERPRINT, 2014, Onac, B. P.

The classical epigene speleogenetic model in which CO2 is considered the main source of acidity has been challenged over the last three decades by observations that revealed cave passages unrelated to groundwater drainage routes and surface topography. Most of these passages show unusual morphologies, such are cupolas, floor feeders (i.e., inlets for deep-seated fluids), and huge irregular-shaped rooms that terminate abruptly, and often a rich and diverse mineral association. A hypogenetic speleogenetic pathway was proposed for this group of caves.
The presence of abundant gypsum deposits in caves with one or more of the passage morphologies listed above, have prompted scientists to suggest a new theory (i.e., sulfuric acid speleogenesis, SAS) of cave development. In the hypogenic SAS model, the source of acidity is the sulfuric acid produced by oxidation of H2S (originating from sulfate reduction or petroleum reservoirs) near or at the water table, where it dissolves the limestone bedrock and precipitates extensive gypsum deposits. SAS is now thoroughly documented from numerous caves around the world, with the best examples coming from the Guadalupe Mountains (NM), Frasassi caves (Italy), selected caves in France, Cueva de Villa Luz (Mexico), and Cerna Valley (SW Romania).
To date, discrimination between epigene and hypogene speleogenetic pathways is made using cave morphology criteria, exotic mineral assemblages, and the predominantly negative δ34S values for the cave sulfates. This presentation highlights the role sulfur and oxygen stable isotope analyses have in discriminating between epigene and hypogene caves.
Based on a number of case studies in caves of the Cerna Valley (Romania), we found that relatively S-depleted isotopic composition of cave minerals alone does not provide enough information to clearly distinguish SAS from other complex speleogenetic pathways. In fact, δ34S values of SAS by-products depend not only on the source of the S, but also on the completeness of S redox reactions. Therefore, similar studies to this are needed to precisely diagnose SAS and to provide information on the S cycle in a given karst system.
Integrating cave mineralogy, passage morphology, and geochemical studies may shed light on the interpretation of polygenetic caves, offering clues to processes, mechanisms, and parameters involved in their genesis (sulfate-dominated).


ISOTOPIC STUDIES OF BYPRODUCTS OF HYPOGENE SPELEOGENESIS AND THEIR CONTRIBUTION TO THE GEOLOGIC EVOLUTION OF THE WESTERN UNITED STATES, 2014, Polyak V. J. , Asmerom Y. , Hill C. A. , Palmer A. N. , Provencio P. P. , Palmer M. V. , Mcintosh W. C. , Decker D. D. , Onac B. P.

Hypogene speleogenesis in the western United States is associated with a deep source of water and gases that rise and mix with shallow aquifer water. Caves are formed below the surface without surface expressions (ie, sinkholes, sinking streams), and byproducts of speleogenesis are precipitated during the late phase of hypogene speleogenesis. These byproducts provide geochemical and geochronological evidence of a region’s geologic history and include gypsum rinds and blocks, elemental sulfur, halloysite-10Å, alunite, natroalunite, and other sulfur-related minerals. The following speleogenetic and speleothemic features are common: alteration rinds, crusts, mammillaries, folia, rafts, and cave spar. The types of hypogene speleogenesis vary and many can be expressed in space and time in relation to paleo-water tables. We identify two general types: (1) H2S-H2SO4-dominated speleogenesis that takes place predominantly near a paleo-water table (a few meters above and below), and (2) CO2-dominated speleogenesis that mostly takes place 10s to 100s of meters below a paleo-water table, with latest-stage imprints within meters of the water table.
The Kane caves in Wyoming, and the Guadalupe Mountains caves in New Mexico and West Texas, are examples of H2S-H2SO4-dominated speleogenesis (also known as sulfuric acid speleogenesis, SAS), where deposits of H2S- and H2SO4-origin are the obvious fingerprints. The Grand Canyon caves in Arizona and Glenwood Caverns in Colorado are examples of CO2-dominated systems, where H2SO4 likely played a smaller role (Onac et al., 2007). Deeper-seated geode-like caves, like the spar caves in the Delaware Basin area, are probably CO2-dominated, and have formed at greater depths (~0.5 ± 0.3 km) below paleo-water tables. Caves in the Black Hills, South Dakota are composite and complex and show evidence for multiple phases of hypogene speleogenesis. In areas such as the Grand Canyon region, these paleo-water tables, when they existed in thick carbonate rock stratigraphy and especially at the top of the thick carbonate rock strata, were likely regionally relatively flat in the larger intact tectonic blocks.
Geochemical studies of these deposits are providing information about the timing of speleogenesis through U-Th, U-Pb, and Ar-dating. In addition, tracer data from isotopes of C, O, S, Sr, and U are indicators of the sources of water and gases involved in speleogenesis. From these studies, novel canyon incision and landscape evolution interpretations are appearing in the literature. Beyond this, the study of these byproduct materials seems to show evidence that the deeply sourced water and gases involved in hypogene speleogenesis in the western United States are generated during tectonic and volcanic activity, and may be related to mantle processes associated with formation of the Rocky Mountains, Colorado Plateau, Basin and Range province, and Rio Grande Rift.


SPELEOGENESIS BY THE SULFIDIC SPRINGS AT NORTHERN SIERRA DE CHIAPAS, MEXICO, BASED ON THEIR WATER CHEMISTRY, 2014, Rosaleslagarde L. , Boston P. J.

Conspicuous brackish sulfidic springs have been described at the northern Sierra the Chiapas, Mexico. These springs are produced by a mixture between regional and local groundwater flow paths. The regional groundwater has an average Total Dissolved Ions of 3081 mg/L so it has a brackish composition. This brackish water is saturated with respect to calcite and dolomite but undersaturated with respect to gypsum, anhydrite and halite. The mass balance and the discharge rate are used to quantify the mass and volume of minerals that are dissolved by the brackish spring water following Appelo and Postma (1993). This quantification will allow comparing the various speleogenetic mechanisms in the area. This is considering the composition of the spring water is relatively constant over time, as it is suggested by periodic measurements at the Cueva de Villa Luz springs during the last 10 years.
Sulfur isotopes in the water are consistent with anhydrite dissolution as the main source of the sulfate to the brackish spring water. Thus, the average 6 mol/L of sulfate in the brackish springs are produced by dissolution of 6 mol of anhydrite after subtracting the sulfate that could result from evapotranspiration of rainwater. Each liter of brackish water dissolved an average of 882 mg of anhydrite, which are equivalent to dissolving 0.36 cm3 of this mineral considering a density of 2.981 g/cm3. Additionally, using the average brackish water discharge rate of 144 L/s, an average of 57 g of anhydrite are being dissolved each second per every liter of brackish water. This is a minimal value because some of the sulfate in the water is used by sulfate-reducing bacteria in the subsurface to produce the hydrogen sulfide in the spring water. The anhydrite subject to dissolution is found interbedded in the Cretaceous carbonates, either from the subsurface at 4,000 m below sea level to the carbonate outcrops.
Similarly, we can calculate the volume of halite that is being dissolved by the brackish springs, considering chloride is a conservative element and subtracting the chloride concentration from the rainwater from that of the spring water following Appelo & Postma (1993). The 22 mol/L of chloride in the brackish water can result from dissolution in the subsurface of 22 moles or 1.3 g of halite per liter of brackish water. This mass of halite dissolved is equal to 0.59 cm3 considering a density of 2.168 g/cm3. Alternatively, 118 g of halite are dissolved per second per each liter of brackish water if we use the average discharge rate of 144 L/s.
Even when the brackish springs are oversaturated with respect to calcite and dolomite, their dissolution is still possible due to the common ion-effect of calcium after anhydrite dissolution and by mixing of waters with different compositions. A range of 10 to 80 % of brackish water from the regional aquifers mixes with fresh water from the local aquifer based on their water chemistry. Additionally, sulfuric acid speleogenesis occurs due to the oxidation of hydrogen sulfide to sulfuric acid.
Finally, the increase in the chloride concentration of the fresh water springs with respect to the concentration in rainwater was used to estimate that from the 4000 mm/y of annual precipitation, only 4%, 158 to 182 mm/y, recharge the aquifers. This low percentage is slightly higher than the 3.3% recharge in marls, marly limestone, silts and clays (Sanz et al., 2011), probably because of the relatively small area of carbonate outcrops over the entire region and the lack of recharge in altitudes higher than 1500 m above sea level.
Sulfuric acid is the most obvious speleogenetic mechanism occurring in the caves of the northern Sierra de Chiapas, Mexico due to the high hydrogen sulfide concentration in the spring water. In addition, the location of the springs at a zone of regional and local discharge where waters from different composition converge and mix, and the amount of mixing calculated suggests mixing is also an important speleogenetic mechanism. However, the depth and the time constrains at which these two hypogenic mechanisms occur is still unknown. The relatively low rainwater recharge rate suggests epigenesis is limited. Most likely, the porosity created by dissolution of anhydrite and halite in the subsurface is occluded by the precipitation of calcite. Chemical modeling and petrography will help to elucidate the order of the reactions occurring in the subsurface.


Determining gypsum growth temperatures using monophase fluid inclusions - Application to the giant gypsum crystals of Naica, Mexico: COMMENT, 2014, Garofalo P. S. , Forti P. , Günther D.

Hydrogeology of northern Sierra de Chiapas, Mexico: A conceptual model based on a geochemical characterization of sulfide-rich karst brackish springs, 2014,

Conspicuous sulfide-rich karst springs flow from Cretaceous carbonates in northern Sierra de Chiapas, Mexico. This is a geologically complex, tropical karst area. The physical, geologic, hydrologic and chemical attributes of these springs were determined and integrated into a conceptual hydrogeologic model. A meteoric source and a recharge elevation below 1500 m are estimated from the spring water isotopic signature regardless of their chemical composition. Brackish spring water flows at a maximum depth of 2000 m, as inferred from similar chemical attributes to the produced water from a nearby oil well. Oil reservoirs may be found at depths below 2000 m. Three subsurface environments or aquifers are identified based on the B, Li+, K+ and SiO2 concentrations, spring water temperatures, and CO2 pressures. There is mixing between these aquifers. The aquifer designated Local is shallow and contains potable water vulnerable to pollution. The aquifer named Northern receives some brackish produced water. The composition of the Southern aquifer is influenced by halite dissolution enhanced at fault detachment surfaces. Epigenic speleogenesis is associated with the Local springs. In contrast, hypogenic speleogenesis is associated with the brackish sulfidic springs from the Northern and the Southern environments.


Depth and timing of calcite spar and “spar cave” genesis: Implications for landscape evolution studies, 2015,

Calcite spar (crystals >1 cm in diameter) are common in limestone and dolostone terrains. In the Guadalupe Mountains, New Mexico and west Texas, calcite spar is abundant and lines small geode-like caves. Determining the depth and timing of formation of these large scalenohedral calcite crystals is critical in linking the growth of spar with landscape evolution. In this study, we show that large euhedral calcite crystals precipitate deep in the phreatic zone (400–800 m) in these small geode-like caves (spar caves), and we propose both are the result of properties of supercritical CO2 at that depth. U-Pb dating of spar crystals shows that they formed primarily between 36 and 28 Ma. The 87Sr/86Sr values of the euhedral calcite spar show that the spar has a signifi cantly higher 87Sr/86Sr (0.710–0.716) than the host Permian limestone (0.706–0.709). This indicates the spar formed from waters that are mixed with, or formed entirely from, a source other than the surrounding bedrock aquifer, and this is consistent with hypogene speleogenesis at signifi cant depth. In addition, we conducted highly precise measurements of the variation in nonradiogenic isotopes of strontium, 88Sr/86Sr, expressed as 88Sr, the variation of which has previously been shown to depend on temperature of precipitation. Our preliminary 88Sr results from the spar calcite are consistent with formation at 50–70 °C. Our fi rst U-Pb results show that the spar was precipitated during the beginning of Basin and Range tectonism in a late Eocene to early Oligocene episode, which was coeval with two major magmatic periods at 36–33 Ma and 32–28 Ma. A novel speleogenetic process that includes both the dissolution of the spar caves and precipitation of the spar by the same speleogenetic event is proposed and supports the formation of the spar at 400–800 m depth, where the transition from supercritical to subcritical CO2 drives both dissolution of limestone during the main speleogenetic event and precipitation of calcite at the terminal phase of speleogenesis. We suggest that CO2 is derived from contemporaneous igneous activity. This proposed model suggests that calcite spar can be used for reconstruction of landscape evolution


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