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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 subsurface flow is see subsurface runoff.?

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Chemistry and Karst, White, William B.
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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 vazante (Keyword) returned 7 results for the whole karstbase:
The Vazante zinc mine, Minas Gerais, Brazil; constraints in willemitic mineralization and fluid evolution, 1999, Lena Virginia Soares Monteiro, Jorge Silva Bettencourt, Baruch Spiro, Rodnei Graca, And Tolentino Flavio De Oliveira
The Vazante Mine is located in the Vazante District, the largest zinc district in Brazil. The Vazante deposit consists dominantly of an unusual willemitic ore. Small sulfide bodies are tectonically imbricated with the willemitic ore, within the Vazante shear zone. Structural styles of deformation and petrographic and isotopic evidence indicate that willemitic mineralization and deformation occurred synchronously during the Neo-Proterozoic. Various generations of hydrothermal veins and hydraulic breccias may pre-date, accompany and overprint the mineralization. Ore-formation temperatures are deduced from stable isotope geothermometry and mineral chemistry of both sulfide bodies and willemitic ore. Temperatures during the main stage of mineralization range from 206 degrees C to 294 degrees C (willemitic ore) and 317 degrees C (sulfides), and reflect the prevailing metamorphic conditions within the shear zone. The fluid from which the gangue minerals of the sulfide bodies precipitated (at 250 degrees C) had an oxygen isotopic average value of delta 18 O = +19.4 per mil. This value appears to reflect the interaction of metamorphic fluid with the carbonate rocks of the Vazante formation. At 250 degrees C, the fluid in equilibrium with the vein mineral phases and willemitic ore assemblage exhibits a uniform oxygen isotopic composition, with an average value of delta 18 O = +11.5 per mil. The positive linear covariance of delta 18 O and delta 13 C ratios of the carbonates is most likely due to the mixing of metamorphic and meteoric fluids. The delta 34 S values of sulfides indicate a direct crustal origin for the sulfur. It is suggested that the sulfur is largely derived from pre-existing sulfide bodies and has been transported by metamorphic fluids. The willemitic ore may have originated from the precipitation of metal in sulfur-poor fluids under oxidized conditions, within the Vazante shear zone.

Formation of Willemite in Hydrothermal Environments, 2003, Brugger J, Mcphail Dc, Wallace M, Waters J,
Willemite (zinc silicate) is the main zinc mineral in some carbonate-hosted ore deposits (e.g., Franklin, New Jersey; Vazante, Brazil; Beltana, South Australia; Kabwe, Zambia). Recent interest in these unconventional zinc deposits has increased because of high zinc grades that exceed 40 wt percent, relatively low environmental impact of ore processing owing to the lack of acid-generating sulfides in the waste, and advances in ore processing technologies. In the past, most metallogenic studies proposed formation of willemite deposits by supergene or hypogene alteration of preexisting sulfide deposits. However, recent data on the Vazante, Beltana, and Kabwe deposits indicate willemite crystallization at temperatures in excess of 150{degrees}C, raising the possibility of primary precipitation from hydrothermal fluids. We use numerical geochemical modeling to examine the formation of willemite under hydrothermal conditions. Activity-activity diagrams reveal that, in the presence of dissolved sulfur and quartz, willemite instead of sphalerite will precipitate under oxidizing (e.g., hematite-stable, sulfate-predominant) and alkaline (pH higher than K feldspar-muscovite-quartz) conditions. Willemite also becomes more stable, relative to sphalerite, at high temperature, and willemite can coexist with magnetite at 300{degrees}C. The stabilities and solubilities of sphalerite, willemite, smithsonite, hydrozincite, and zincite were calculated for wide ranges of temperature (25{degrees}-300{degrees}C), chloride concentration, dissolved sulfur and carbon concentrations, pH, quartz saturation, and oxidation potential. Plots of the solubility of the different minerals as a function of two variables (e.g., temperature and redox state; pH and redox state) allow us to predict the effects of changing chemical conditions, which in turn permits an estimate of the efficiency of particular precipitation processes. Cooling is an effective process for precipitating sphalerite but not willemite, whereas pH increase (e.g., by acidic fluids reacting with carbonates) is effective for precipitating willemite but not sphalerite. Dynamic geochemical models that simulate physicochemical processes are used to understand the formation of the Beltana willemite deposit in the Adelaide geosyncline of South Australia. This small, high grade deposit (850,000 t at 36% Zn) is hosted in dolomite of the Cambrian Ajax Limestone, next to a tectonic contact with the diapiric, halite-bearing clastic sediments of the Callanna Group. The orebody is associated with hematite alteration and is characterized by the total absence of sulfides; willemite is the only zinc ore mineral, and the arsenate hedyphane (Ca2Pb3[AsO4]3Cl) is the main lead mineral. The model results show that willemite will precipitate in response to water-rock interaction and fluid mixing processes at temperatures above 120{degrees}C. The presence of arsenate in the hydrothermal fluid is likely to have been important at Beltana; in arsenate-absent models sulfate is reduced to sulfide by the precipitation of ferrous iron as hematite, resulting in the precipitation of sphalerite and galena. In contrast, in models including arsenate the reduction of sulfate to sulfide is inhibited and willemite is predicted to precipitate

Nonsulfide and sulfide-rich zinc mineralizations in the Vazante, Ambrsia and Fagundes deposits, Minas Gerais, Brazil: Mass balance and stable isotope characteristics of the hydrothermal alterati, 2007, Soares Monteiro Lena Virgí, Nia, Bettencourt Jorge Silva, Juliani Caetano, De Oliveira Tolentino Flvio
The Vazante Group hosts the Vazante nonsulfide zinc deposit, which comprises high-grade zinc silicate ore (ZnSiO4), and late-diagenetic to epigenetic carbonate-hosted sulfide-rich zinc deposits (e.g. Morro Agudo, Fagundes, and Ambrósia). In the sulfide-rich deposits, hydrothermal alteration involving silicification and dolomitization was related with ground preparation of favorable zones for fluid migration (e.g. Fagundes) or with direct interaction with the metalliferous fluid (e.g. Ambrósia). At Vazante, hydrothermal alteration resulted in silicification and dolomite, siderite, jasper, hematite, and chlorite formation. These processes were accompanied by strong relative gains of SiO2, Fe2O3(T), Rb, Sb, V, U, and La, which are typically associated with the nonsulfide zinc mineralization. All sulfide-rich zinc ores in the district display a similar geochemical signature suggesting a common metal source from the underlying sedimentary sequences. Oxygen and carbon isotope compositions of hydrothermally altered rocks reveal a remarkable alteration halo at the Vazante deposit, which is not a notable feature in the sulfide-rich deposits. This pattern could be attributed to fluid mixing processes involving the metalliferous fluid and channelized meteoric water, which may control the precipitation of the Vazante nonsulfide ore. Sulfide deposition resulted from fluid?rock interaction processes and mixing between the ascending metalliferous fluids and sulfur-rich tectonic brines derived from reduced shale units.

Isotope geochemistry of the mafic dikes from the Vazante nonsulfide zinc deposit, Brazil, 2007, Babinski M. , Monteiro L. V. S. , Fetter A. H. , Bettencourt J. S. , Oliveir T. F.
The Vazante Group, located in the northwestern part of Minas Gerais, hosts the most important zinc mine in Brazil, the Vazante Mine, which represents a major known example of a hypogene nonsulfide zinc deposit. The main zinc ore is represented by willemite and differs substantially from other deposits of the Vazante-Paracatu region, which are sulfide-dominated zinc-lead ore. The age of the Vazante Group and the hosted mineralization is disputable. Metamorphosed mafic dikes (metabasites) that cut the metasedimentary sequence and are affected by hydrothermal processes recently were found and may shed light on the geochronology of this important geological unit. Zircon crystals recovered from the metabasites are xenocrystic grains that yield U?Pb conventional ages ranging from 2.1 to 2.4 Ga, so the basement of the Vazante Group is Paleoproterozoic or has metasedimentary rocks whose source area was Paleoproterozoic. Pb isotopes determined for titanite separated from the metabasites have common, nonradiogenic Pb compositions, which prevents determination of their crystallization age. However, the Pb signatures observed for the titanite crystals are in agreement with those determined for galena from the carbonate-hosted Zn?Pb deposits hosted by the Vazante Group, including galena from minor sulfide ore bodies of the Vazante deposit. These similarities suggest that the metalliferous fluids that affected the metabasites may have been those responsible for galena formation, which could imply a similar lead source for both nonsulfide and sulfide zinc deposits in the Vazante?Paracatu district. This common source could be related to deep-seated, basin-derived, metalliferous fluids associated with a long-lived hydrothermal system related to diagenesis and deformation of the Vazante Group during the Neoproterozoic.

THE INFLUENCE OF HYPOGENE AND EPIGENE SPELEOGENESIS IN THEEVOLUTION OF THE VAZANTE KARST MINAS GERAIS STATE, BRAZIL, 2009, Bittencourt C. , Auler A. , Neto J. , Bessa V. , Silva M.

The advanced state of karsti?cation in the metadolomites of the Neoproterozoic Vazante Group has resulted in several geotechnical and hydrogeological problems in an underground zinc mine located in the city of Vazante, state of Minas Gerais, central Brazil, that have prompted detailed hydrogeological studies. The continuity of karsti?cation at depths below the regional base level suggests that hypogenic karsti?cation, driven by migration of ?uids from below due to hydrostatic pressure or other sources of energy may be a major player in the area. In this work several tools were used to understand the mechanisms of karsti?cation in the area, focusing on the relationship between karsti?cation and the location of ore bodies. The in?uence of both epigene and hypogene processes appears in the Vazante karstic evolution and has a relationship with the cave size. The study demonstrates that the size of voids decreases with depth. The largest cavities (greater than 15 meters) occur above the regional base level. This region is represented by the vadose zone, where epigenic karst processes predominate. Below this elevation, up to 250 meters in depth, a combination of epigene and hypogene processes occurs and the diameter of voids tends to decrease, being usually less than 10 meters. Below 250 meters, the phenomena of karsti?cation are strictly hypogenic and the diameter of voids is limited to less than 5 meters.


Hypogene Speleogenesis and Karst Hydrogeology of Artesian Basins, 2009,

The volume contains papers presented during the International Conference held May 13 through 17, 2009 in Chernivtsi, Ukraine.

The PDF file contains cover, title and contents pages. Download and save this file to your disk and use hyperlinked titles of papers in the content list to download PDF files of individual papers. 

CONTENTS

PRINCIPAL FEATURES OF HYPOGENE SPELEOGENESIS
Alexander Klimchouk

HYPOGENE CAVE PATTERNS
Philippe Audra, Ludovic Mocochain, Jean-Yves Bigot, and Jean-Claude Nobécourt

MORPHOLOGICAL INDICATORS OF SPELEOGENESIS: HYPOGENIC SPELEOGENS
Philippe Audra, Ludovic Mocochain, Jean-Yves Bigot, and Jean-Claude Nobécourt

HYPOGENE CAVES IN DEFORMED (FOLD BELT) STRATA: OBSERVATIONS FROM EASTERN AUSTRALIA AND CENTRAL EUROPE
R.A.L. Osborne

IDENTIFYING PALEO WATER-ROCK INTERACTION DURING HYDROTHERMAL KARSTIFICATION: A STABLE ISOTOPE APPROACH
Yuri Dublyansky and Christoph Spötl

MICROORGANISMS AS SPELEOGENETIC AGENTS: GEOCHEMICAL DIVERSITY BUT GEOMICROBIAL UNITY
P.J.Boston, M.N. Spilde, D.E. Northup, M.D. Curry, L.A. Melim, and L. Rosales-Lagarde

SIDERITE WEATHERING AS A REACTION CAUSING HYPOGENE SPELEOGENESIS: THE EXAMPLE OF THE IBERG/HARZ/GERMANY Stephan Kempe

SIMULATING THE DEVELOPMENT OF SOLUTION CONDUITS IN HYPOGENE SETTINGS
C. Rehrl, S. Birk, and A.B. Klimchouk

EVOLUTION OF CAVES IN POROUS LIMESTONE BY MIXING CORROSION: A MODEL APPROACH
Wolfgang Dreybrodt, Douchko Romanov, and Georg Kaufmann

SPELEOGENESIS OF MEDITERRANEAN KARSTS: A MODELLING APPROACH BASED ON REALISTIC FRACTURE NETWORKS
Antoine Lafare, Hervé Jourde, Véronique Leonardi, Séverin Pistre, and Nathalie Dörfliger

GIANT COLLAPSE STRUCTURES FORMED BY HYPOGENIC KARSTIFICATION: THE OBRUKS OF THE CENTRAL ANATOLIA, TURKEY
C. Serdar Bayari, N. Nur Ozyurt, and Emrah Pekkans

ON THE ROLE OF HYPOGENE SPELEOGENESIS IN SHAPING THE COASTAL ENDOKARST OF SOUTHERN MALLORCA (WESTERN MEDITERRANEAN)
Joaquín Ginés, Angel Ginés, Joan J. Fornós, Antoni Merino and Francesc Gràcia

HYPOGENE CAVES IN THE APENNINES (ITALY)
Sandro Galdenzi

STEGBACHGRABEN, A MINERALIZED HYPOGENE CAVE IN THE GROSSARL VALLEY, AUSTRIA
Yuri Dublyansky, Christoph Spötl, and Christoph Steinbauer

HYPOGENE CAVES IN AUSTRIA
Lukas Plan, Christoph Spötl, Rudolf Pavuza, Yuri Dublyansky

KRAUSHÖHLE: THE FIRST SULPHURIC ACID CAVE IN THE EASTERN ALPS (STYRIA, AUSTRIA) (Abstract only)
Lukas Plan, Jo De Waele, Philippe Audra, Antonio Rossi, and Christoph Spötl

HYDROTHERMAL ORIGIN OF ZADLAŠKA JAMA, AN ANCIENT ALPINE CAVE IN THE JULIAN ALPS, SLOVENIA
Martin Knez and Tadej Slabe

ACTIVE HYPOGENE SPELEOGENESIS AND THE GROUNDWATER SYSTEMS AROUND THE EDGES OF ANTICLINAL RIDGES
Amos Frumkin

SEISMIC-SAG STRUCTURAL SYSTEMS IN TERTIARY CARBONATE ROCKS BENEATH SOUTHEASTERN FLORIDA, USA: EVIDENCE FOR HYPOGENIC SPELEOGENESIS?
Kevin J. Cunningham and Cameron Walker

HYPOGENE SPELEOGENESIS IN THE PIEDMONT CRIMEA RANGE
A.B. Klimchouk, E.I. Tymokhina and G.N. Amelichev

STYLES OF HYPOGENE CAVE DEVELOPMENT IN ANCIENT CARBONATE AREAS OVERLYING NON-PERMEABLE ROCKS IN BRAZIL AND THE INFLUENCE OF COMPETING MECHANISMS AND LATER MODIFYING PROCESSES
Augusto S. Auler

MORPHOLOGY AND GENESIS OF THE MAIN ORE BODY AT NANISIVIK ZINC/LEAD MINE, BAFFIN ISLAND, CANADA: AN OUTSTANDING EXAMPLE OF PARAGENETIC DISSOLUTION OF CARBONATE BEDROCKS WITH PENE-CONTEMPORANEOUS PRECIPITATION OF SULFIDES AND GANGUE MINERALS IN A HYPOGENE SETTING
Derek Ford

THE INFLUENCE OF HYPOGENE AND EPIGENE SPELEOGENESIS IN THE EVOLUTION OF THE VAZANTE KARST MINAS GERAIS STATE, BRAZIL
Cristian Bittencourt, Augusto Sarreiro Auler, José Manoel dos Reis Neto, Vanio de Bessa and Marcus Vinícios Andrade Silva

HYPOGENIC ASCENDING SPELEOGENESIS IN THE KRAKÓW-CZĘSTOCHOWA UPLAND (POLAND) ? EVIDENCE IN CAVE MORPHOLOGY AND SURFACE RELIEF
Andrzej Tyc

EVIDENCE FROM CERNA VALLEY CAVES (SW ROMANIA) FOR SULFURIC ACID SPELEOGENESIS: A MINERALOGICAL AND STABLE ISOTOPE STUDY
Bogdan P. Onac, Jonathan Sumrall, Jonathan Wynn, Tudor Tamas, Veronica Dărmiceanu and Cristina Cizmaş

THE POSSIBILITY OF REVERSE FLOW PIRACY IN CAVES OF THE APPALACHIAN MOUNTAIN BELT (Abstract only)
Ira D. Sasowsky

KARSTOGENESIS AT THE PRUT RIVER VALLEY (WESTERN UKRAINE, PRUT AREA)
Viacheslav Andreychouk and Bogdan Ridush

ZOLOUSHKA CAVE: HYPOGENE SPELEOGENESIS OR REVERSE WATER THROUGHFLOW?
V. Eirzhyk (Abstract only)

EPIGENE AND HYPOGENE CAVES IN THE NEOGENE GYPSUM OF THE PONIDZIE AREA (NIECKA NIDZIAŃSKA REGION), POLAND
Jan Urban, Viacheslav Andreychouk, and Andrzej Kasza

PETRALONA CAVE: MORPHOLOGICAL ANALYSIS AND A NEW PERSPECTIVE ON ITS SPELEOGENESIS
Georgios Lazaridis

HYPOGENE SPELEOGENESIS IN MAINLAND NORWAY AND SVALBARD?
Stein-Erik Lauritzen

VILLA LUZ PARK CAVES: SPELEOGENESIS BASED ON CURRENT STRATIGRAPHIC AND MORPHOLOGIC EVIDENCE (Abstract only)
Laura Rosales-Lagarde, Penelope J. Boston, Andrew Campbell, and Mike Pullin

HYPOGENE KARSTIFICATION IN SAUDI ARABIA (LAYLA LAKE SINKHOLES, AIN HEETH CAVE)
Stephan Kempe, Heiko Dirks, and Ingo Bauer

HYPOGENE KARSTIFICATION IN JORDAN (BERGISH/AL-DAHER CAVE, UWAIYED CAVE, BEER AL-MALABEH SINKHOLE)
Stephan Kempe, Ahmad Al-Malabeh, and Horst-Volker Henschel

ASSESSING THE RELIABILITY OF 2D RESISTIVITY IMAGING TO MAP A DEEP AQUIFER IN CARBONATE ROCKS IN THE IRAQI KURDISTAN REGION
Bakhtiar K. Aziz and Ezzaden N. Baban

FEATURES OF GEOLOGICAL CONDITIONS OF THE ORDINSKAYA UNDERWATER CAVE, FORE-URALS, RUSSIA
Pavel Sivinskih

INIAAIIINOE AEIIAAIIIAI NIAEAIAAIACA AI?II-NEEAA?AOIE IAEANOE CAIAAIIAI EAAEACA
A.A.Aao?ooaa

AEOAEIIIA NO?IAIEA AEA?IAAINOA?U: IIAAEU AA?OEEAEUIIE CIIAEUIINOE
A.I. Eaoaaa

?IEU EA?NOA A OI?IE?IAAIEE NIEAIUO AIA E ?ANNIEIA IEAI?ENEIAI AANNAEIA
Aeaenaia? Eiiiiia, Na?aae Aeaenaaa, e Na?aae Nooia


STYLES OF HYPOGENE CAVE DEVELOPMENT IN ANCIENT CARBONATE AREAS OVERLYING NON-PERMEABLE ROCKS IN BRAZIL AND THE INFLUENCE OF COMPETING MECHANISMS AND LATER MODIFYING PROCESSES, 2009, Augusto S. Auler

A significant proportion of the karst areas in Brazil develop over ancient cratonic or tectonically stable zones overlying Precambrian quartzites or Archaean crystalline basement (granite, gneiss, schist). In such settings, due to the low transmissivity and highly anisotropic nature of the bedrock, major groundwater flow of regional scale tends to be restricted, and diffuse ascending cross-formational flow into the carbonate is limited to a few favourable input zones. Nevertheless, caves displaying hypogene features occur in several areas, although few contain the full suite of speleogenetic forms commonly found in “classic” better studied areas of Europe and North America. Major known hypogene caves in Brazil tend to be located in zones bordering the more stable cratonic areas, such as in Vazante and Toca da Boa Vista karst areas, where fault zones are likely candidates for providing ascending flow paths towards the carbonate. The absence of transmissive beds above the carbonate limits the existence of outflow routes. Brazilian hypogene caves develop in mostly horizontally bedded or gently dipping bedrock and typically do not display the three-dimensional character of many hypogene caves elsewhere. The speleogenetic role of competing mechanisms such as sulphuric acid dissolution due to pyrite oxidation and condensation corrosion tend to overprint original forms as well as produce similar convergent features.


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