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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 relict cave is abandoned, inactive cave segment, left when the water that formed it is diverted elsewhere, normally due to rejuvenation, continuing cave development and increasing karstic maturity. relict unmodified phreatic passage segments are abandoned in the vadose zone, where they may remain dry, retaining a typical phreatic morphology, or be invaded and modified to a keyhole profile by new streams. ages of relict caves vary greatly and due to lack of stream-flow breakdown and speleothem deposition may become the dominant processes. relict caves are commonly referred to incorrectly as fossil caves [9].?

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

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KarstBase a bibliography database in karst and cave science.

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 zinc (Keyword) returned 60 results for the whole karstbase:
Showing 16 to 30 of 60
Sinkholes in karst mining areas in China and some methods of prevention, 1999,
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Li G. Y. , Zhou W. F. ,
Mining of coal, lead and zinc, gold, and iron ore deposits in karst areas has been closely associated with sinkholes in China. Surface collapse causes an increase in mine water drainage and the possibility of major water inflow from karst aquifers, which threatens the environment in mining areas and endangers the mine safety. A combination of factors including soil weight, buoyancy, suffusion process and vacuum suction can contribute to the sinkhole formation. The key measures to prevent sinkholes in mining areas are to control the amount of mine drainage, reduce water level fluctuation, seal-off karst conduits and subsurface cavities in the overlying soil, prevent water inflow, and/or to increase gas pressure in the karst conduits. (C) 1999 Elsevier Science B.V. All rights reserved

The Vazante zinc mine, Minas Gerais, Brazil; constraints in willemitic mineralization and fluid evolution, 1999,
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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.

Hydrogeologic modeling of the genesis of carbonate-hosted lead-zinc ores, 1999,
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Grant Garven, Martin S. Appold, Vera I. Toptygina, Timothy J. Hazlett,

Combustion Oil pollution of Pazinska Jama - a major Ecological incident in the Karst., 1999,
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Kuhta M.
The pollution of Pazincica river occurred in August 1997 as a consequence of uncontrolled leakage of vast quantities of oil from a ruptured pipe that connects the oil reservoir and the oil combustion facility of the factory KTI "Pazinka". The oil together with waste waters from the factory first discharged into the watercourse Saltarija and then flowed into the downstream part of Pazincica River. The spilled combustion oil was a threat to the groundwater of the wider region of Istria so extensive and intensive measures were undertaken for its removal. Within these prevention measures two speleological investigations of the Pazincica ponor (Pazinska jama- Foiba di Pisino) were undertaken. It was determined that due to favourable hydrological conditions (the discharge of Pazincica river was 50 l/s) and the fast reaction time of the intervention, only small quantities of oil managed to enter the ponor. On the other hand approximately 168 m3 of combustion oil was detached from the surface watercourse. Unfortunately the speleological examination of the ponor determined a high degree of underground pollution caused by discharge of waste waters from the city of Pazin and its industries into the Pazincica River. Also traces of past unregistered combustion oil pollution were found within the cavern.

Influence of heavy rainfalls in July 1997 on water flooding of zinc and lead ore mines in Olkusz area. [in Polish], 2000,
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Adamczyk Zbigniew, Motyka Jacek

Geographic information systems analysis of geologic controls on the distribution on dolines in the Ozarks of south-central Missouri, USA, 2000,
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Orndorff Randall C. , Weary David J. , Lagueux Kerry M.

The geologic controls on the distribution and development of dolines in the Salem Plateau of the Ozark Plateaus Province, south-central Missouri, USA, was statistically analyzed by using a geographic information system. The controls include lithostratigraphy, geologic structure, slope, and depth to water table. Area and point data for 2,613 dolines in two 30'¥60' quadrangles were compiled on a 30-meter grid. The percent area of dolines was calculated for five lithostratigraphic units, and it was determined that the Jefferson City Dolomite and Roubidoux Formation have the highest density of dolines. A focal sum neighborhood analysis was performed to determine if the distribution of dolines had any clustering or linearity that may suggest structural control. A northwest alignment of doline clusters occurs along a projection of the Bolivar-Mansfield fault zone in south-central Missouri. Most dolines in the study area occur on the plateau areas and on gentle slopes rather than in the highly dissected areas. Intense fracturing near regional fault zones may enhance doline development on the plateau areas. An understanding of the karst system is important for better land-use management practices in the Ozarks, including conservation of natural resources, ground-water management, and environmental protection, especially because the study area includes potential economic lead and zinc mineralization.

Compositional zoning and element partitioning in nickeloan tourmaline from a metamorphosed karstbauxite from Samos, Greece, 2001,
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Henry Darrell J. , Dutrow Barbara L. ,
Blue-green nickeloan tourmaline from a micaceous enclave of a marble from Samos, Greece, contains unusually high concentrations of Ni (up to 3.5 wt% NiO), Co (up to 1.3 wt% CoO), and Zn (up to 0.8 wt% ZnO). The polymetamorphic karstbauxite sample has an uncommon assemblage of nickeloan tourmaline, calcite, zincian staurolite, gahnite, zincohogbomite, diaspore, muscovite, paragonite, and rutile. The complex geologic history is reflected in multi-staged tourmaline growth, with cores that represent detrital fragments surrounded by two-staged metamorphic overgrowths. Zone-1 metamorphic overgrowths, which nucleated next to detrital cores, are highly asymmetric and exhibit compositional polarity such that narrow overgrowths of brown schorl developed at the (-) c-pole are enriched in Mg, Ti, and F, and depleted in Al, Fe, and X-site vacancies (X{square}) relative to wider, gray-blue schorl-to-foitite overgrowths developed at the () c-pole. Volumetrically dominant Zone-2 overgrowths are strongly zoned nickeloan dravites with a continuous increase in Mg, Co, Ca, and F at the expense of Fe, Zn, Cr, and V from the Zone-1 interface to the outermost rim. Within Zone 2, Ni reaches a maximum of 0.5 apfu before decreasing in the outer 20-40 {micro}m. Zone-2 overgrowths also exhibit compositional polarity such that, at the (-) c-pole, overgrowths are enriched in Mg, F, Na, Ca, and Cr relative to overgrowths at the () c-pole that are, in turn, enriched in Al, Fe, Ni, Co, and X{square}. Element partitioning involving tourmaline rims and coexisting minerals indicates that relative partitioning of Ni is tourmaline >> staurolite > gahnite; Co is tourmaline > staurolite > gahnite; and Zn is gahnite > staurolite >> tourmaline

Origin of iron-rich Mississippi Valley-type deposits, 2001,
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Marie James St, Kesler Stephen E. , Allen Cameron R. ,
The abundance of iron in Mississippi Valley-type lead-zinc deposits and districts varies greatly; some deposits contain large amounts and others are almost free of iron. Iron in Mississippi Valley-type deposits is largely paragenetically early pyrite or marcasite that was replaced by sphalerite and galena, often in the central part of the deposit or district. Sedimentary exhalative and Irish-type base metal deposits, which also form from basinal brines, have similar variations in iron content. Calculated metal contents of brines in equilibrium with galena, sphalerite, and pyrite show that iron is significantly more abundant than lead and zinc in high-temperature (>200 {degrees}C), relatively acid brines with low sulfur contents, whereas zinc dominates under most other conditions, including brines with high temperatures and high sulfur contents. These results suggest that iron-rich Mississippi Valley-type deposits form from brines expelled from the deepest, hottest parts of sedimentary basins

Geologic framework of the Ozarks of South-Central Missouri Contributions to a Conceptual Model of Karst, 2001,
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Orndorff R. C. , Weary D. J. , Sebela S.

A geologic framework is required to understand the environmental impact of proposed mining of lead and zinc on large springs in the karst area of south-central Missouri. Information about lithologies, faults, joints, and karst features (sinkholes, caves, and springs) contributes to the development of a conceptual model of karst hydrogeology. Conduits and caves along bedding planes and joints provide avenues for ground-water recharge, movement, and discharge. The trend of joints was studied to determine if they controlled the orientation of cave passages and conduits. The data show that cave passages are curvilinear and do no correlate well with measured joint trends. Instead, stratigraphy, bedding-plane dip, and local base level affect conduit and cave development. The majority of caves in south-central Missouri have developed within stromatolitic dolomite horizons beneath sandstone beds. It is thought that the sandstone beds act as confining units allowing artesian conditions and mixing to occur beneath them, thus, enhancing dissolution. Joints and the high primary porosity of the stromatolitic dolomite beds form openings in the bedrock that initiate solution. Where a solution-widened joint intersects a bedding plane, lateral movement of ground water is controlled by the bedding plane.

Cadmium and zinc adsorption maxima of geochemically anomalous soils (Oxisols) in Jamaica, 2003,
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Davies Be, Vaughan J, Lalor Gc, Vutchkov M,
Soil samples were collected from a Miocene limestone area of Jamaica (Manchester Parish) where unusual accumulations of Cd and other metals have been described previously. The source of the metals is natural (geological). The soils are aluminous Oxisols and, geochemically, are closely similar to local karst bauxite deposits. For comparison a karst bauxite sample was collected from Alabama (USA) and an Ultisol sample from South Carolina (USA). All the Jamaican soils were in the pH range neutral to slightly alkaline and CaCO3 contents ranged from 1.3 to 23.1 %. Mean total Cd = 102.5 mg/kg (range 13.6-191.8 mg/kg) and mean Zn = 362.6 (range = 125.8-683.3) mg/kg. These values are higher than world averages. The mean readily exchangeable Cd was 0.05 (range 0.01-0.15) mmol/kg and for Zn mean = 0.02 (range 0.01-0.02) mmol/kg. Adsorption data were obtained experimentally and modelled using the Langmuir isotherm. For the Manchester soils the mean Cd adsorption maximum was 9.15 (range 2.26-32.0) mmol/kg; the values were higher than the karst bauxite sample (0.08 mmol/kg) or the Ultisol (0.08 mmol/kg). Reliable Zn isotherms were not obtained for all soils; for three Manchester soils the mean Zn sorption maximum was 2.99 mmol/kg compared with 3.13 mmol/kg for Cd in the same three soils. Mean Al and Fe values are 38.7% Al2O3 and 17.7% Fe2O3 compared with the Ultisol (14.5% Al2O3,11.3% Fe2O3) and the bauxite (52.6% Al2O3, 0.7%Fe2O3). Interpretation of the major element values and the known mineralogy of the soils implies that the high adsorption maxima of the Manchester soils can best be explained by their calcareous nature. It is concluded that the Manchester soils have ample adsorption capacity to trap any incoming Cd or Zn solutes

The Shaimerden Supergene Zinc Deposit, Kazakhstan: A Preliminary Examination, 2003,
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Boland Mb, Kelly Jg, Schaffalitzky C,
The Shaimerden supergene zinc deposit in the southern Urals Mountains is located in the province of Kostanai in northwest Kazakhstan. It lies at the southern end of the Kostanai megasyncline, a north-northeast-trending, structurally controlled area of lower Paleozoic clastic and carbonate sedimentary rocks and volcanic rocks. A zinc-lead resource estimated at 4,645,100 tonnes at 21.06 percent Zn has been defined. The deposit is hosted within a sequence of intertidal to open-marine carbonates and evaporites of Visean (Early Carboniferous) age. Although drilling to date has not intersected a fault, significant faulting in the area is suggested by the presence of polymict debris flows comprising a wide range of carbonate facies and by large variations in micropaleontologic dates. Sulfide deposits replaced hydrothermally dolomitized carbonates and were subsequently reworked into polymict conglomerates of probable Carboniferous age that were deposited in a marine environment. Weathering of the sulfide mineral deposits took place during the Triassic Period, following uplift during the late Paleozoic. The weathering occurred in situ, and small intervals of relict sulfides were preserved in the center of the deposit. The degree of weathering increases outward from the center of the deposit, which passes from massive sulfide to massive hemimorphite-smithsonite to weathered clays with hemimorphite-smithsonite fragments. The supergene minerals are overlain by bauxitic clays of Cretaceous age and Quaternary silty soils and sands

The 'Calamine' of Southwest Sardinia: Geology, Mineralogy, and Stable Isotope Geochemistry of Supergene Zn Mineralization, 2003,
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Boni M, Gilg Ha, Aversa G, Balassone G,
The mining district of southwest Sardinia, Italy, is one of the classic areas where primary carbonate-hosted Zn-Pb sulfide ores are associated with a relatively thick secondary oxidation zone containing Zn (hydroxy-)carbonates and silicates, the so-called 'calamine,' exploited until the 1970s. The extent of the capping oxidized ore zones, reaching deep below the surface, is generally independent of the present-day water table. The base of the oxidation profile containing nonsulfide Zn minerals in various uplifted blocks in the Iglesiente area can be both elevated above or submerged below the recent water table. The genesis of the ores is therefore considered to be related to fossil, locally reactivated, oxidation phenomena. The mineralogy of the nonsulfide mineralization is generally complex and consists of smithsonite, hydrozincite, and hemimorphite as the main economic minerals, accompanied by iron and manganese oxy-hydroxides and residual clays. This study places the secondary ores in the context of the tectonostratigraphic and climatic evolution of Sardinia and includes a petrographic and mineralogic study of the most abundant minerals, relating the mineralogy of secondary Zn and Pb carbonates to their stable C and O isotope geochemistry and constraining the origin of the oxidizing fluids and the temperature of mineralization. The{delta} 18OVSMOW values of smithsonite are homogeneous, regardless of crystal morphology, position, and mine location (avg. 27.4 {} 0.9{per thousand}). This homogeneity points to a relatively uniform isotopic composition of the oxidation fluid and corresponding formation temperatures of 20{degrees} to 35{degrees}C. Considering the karstic environment of smithsonite formation in southwest Sardinia, this high temperature could be due to heat release during sulfide oxidation. The carbon isotope compositions of secondary Zn carbonates display considerable variations of more than 9 per mil ({delta}13CVPDB from -0.6 to -10.4{per thousand}). This large range indicates participation of variable amounts of reduced organic and marine carbonate carbon during sulfide oxidation. The isotopic variation can be related to a variation in crystal morphologies of smithsonite, reflecting different environments of formation with respect to water table oscillations in karstic environments (upper to lower vadose to epiphreatic). The same range in{delta} 13C isotope values is displayed by the calcite associated with Zn carbonates and by recent speleothems. The most reliable time span for the deposition of bulk calamine ore in southwest Sardinia ranges from middle Eocene to Plio-Pleistocene, although further multiple reactivation of the weathering profiles, peaking within the warm interglacial periods of the Quaternary, cannot be excluded

Nonsulfide Zinc Mineralization in Europe: An Overview, 2003,
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Boni M, Large D,
A number of occurrences and deposits of nonsulfide zinc ores in Europe were the historical basis for the development of the zinc mining and smelting industry. The principal occurrences in Silesia (Poland), Sardinia (Italy), and northern Spain are described. These deposits are products of the supergene oxidation of primary carbonate-hosted sulfide minerals during the complex interplay of tectonic uplift, karst development, changes in the level of the water table, and weathering. The nonsulfide zinc mineral deposits in the Irish Midlands may represent an example of surface oxidation of primary sulfide mineral deposits, redeposition, and preservation under glacial till. The willemite-dominated mineralization at La Calamine, Belgium, may be related to paleoweathering or be of possible hydrothermal origin, similar to other willemite deposits in the world

Formation of Willemite in Hydrothermal Environments, 2003,
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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

Geology of the Beltana Willemite Deposit, Flinders Ranges, South Australia, 2003,
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Groves Iain M. , Carman Cris E. , Dunlap W. James,
Beltana is a high-grade hypogene willemite deposit hosted in Lower Cambrian carbonate rocks in the Arrowie basin, northern Flinders Ranges, South Australia. It is situated adjacent to a major growth fault on the basin margin. Ooid grainstone units of the Woodendinna Dolomite and units of Archaeocyathid-rich Wilkawillina Limestone are the main host lithologies. Lead minerals in subeconomic quantities are also present in karstic collapse breccias surrounding the willemite orebodies. Mineralization is structurally controlled and associated with brecciation and extensive hematite-rich hydrothermal zincian dolomitization. Ore minerals include willemite and coronadite with lesser mimetite, hedyphane, and smithsonite. Late-stage gangue minerals include manganocalcite, dolomite, and minor quartz. The texture of willemite is heterogeneous, resulting from various depositional mechanisms such as partial to massive replacement of the carbonate host rock, internal sedimentation, fracture fill, brecciation, and vein fill. On the periphery of the deposit, smithsonite formed by weathering of willemite. Beltana is centered on a karstic collapse breccia that extends at least 100 m vertically, formed in part through corrosion by acidic ore solutions. The geochemical signature of the orebody includes high levels of Zn, Pb, Cd, As, and Mn. Notably, silver is absent from the deposit and sulfur concentrations are low (<20 ppm). Fluid inclusion studies yield a low minimum temperature range of ore deposition between 50{degrees} and 170{degrees}C. K-Ar dating of coronadite associated with the willemite orebody indicates an age of formation of ~ 435 {} 5 Ma. Premining resources of willemite ore were 850,000 t at 36 percent Zn, and an associated body of subeconomic lead contained more than 800,000 t at 8.9 percent Pb, 3.9 percent Zn and 1 percent As. The deposit has some similarities with Mississippi Valley-type deposits but differs in ore and alteration mineral assemblages

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