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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 lime is calcium oxide, cao; used loosely and incorrectly in referring to limestone [10].?

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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 sulfide (Keyword) returned 118 results for the whole karstbase:
Showing 31 to 45 of 118
Speleogenesis in the Picos de Europa massif, Northern Spain, 2000, Fernandezgibert E. , Calaforra J. M. , Rossi C.
The Picos de Europa mountain range in Northern Spain represents one of the most important alpine karsts in the world, containing a great concentration of deep limestone caves. It comprises Carboniferous limestones with thicknesses up to 2000 m and severely deformed by tectonic action. The structure and geological evolution, fracturing and Quaternary glaciation are among the main factors influenced the development of the caves. This paper proposes a speleogenetic model of the evolution, with an initial stage during which a Permo-Triassic cover provided semiconfinement for the entire carbonate series. Under these circumstances, the earliest known phreatic conduits were formed. Occasional relict sediments in them are related to the erosion of the cover. During the second stage, with the uplift of the massif, the cover was eroded and vadose conditions established; they were linked to glacial processes that intensified karstification, creating an unsaturated zone almost 2000 m thick. The karstification and vadose entrenchment in this zone are especially marked along preferential flow paths coinciding with pre-existing dolomitized and sulfide-mineralized fractures in the massif. These fractures may also have played a precursor role in the karstic evolution of the massif, as the source for more aggressive waters with a higher content of weak acids due to the oxidation of sulfides.

Some case studies of speleogenesis by sulfuric acid, 2000, Lowe D. J. , Bottrell S. H. , Gunn J.
Minerals that can weather to produce sulfuric acid directly or indirectly, with or without microbial mediation, occur as trace components in most carbonate sequences, but they are more concentrated at specific horizons. The latter comprise beds of atypical lithology, together termed inception horizons, and they are commonly associated with breaks between major depositional cycles. Some cycle boundaries are marked by concentrations of sulfide minerals, particularly pyrite, that are readily oxidized to generate sulfuric acid. Cycle boundaries may also be marked by the presence of primary evaporite minerals such as gypsum, and their removal by direct dissolution or by their reduction to hydrogen sulfide may be implicated in early porosity development. Though few caves in carbonate sequences are largely, or entirely, the product of calcite dissolution by sulfuric acid or of evaporite removal, such processes may play an important role in cave inception. This chapter examines a number of situations where processes other than carbonic acid dissolution have played an important role in secondary porosity generation and influenced subsequent speleogenesis.

Hydrogeologic control of cave patterns, 2000, Palmer A. N.
Cave patterns are controlled by a hierarchy of hydrogeologic factors. The location and overall trend of a cave depends on the distribution of recharge and discharge points within the karst aquifer. Specific cave patterns, i.e. branchwork vs. maze patterns, are controlled mainly by the nature of the groundwater recharge. Individual passage configurations are determined by the structural nature of the bedrock and by the geomorphic evolution of the aquifer. The origin of branchwork caves is favored by point recharge sources of limited catchment area. Floodwater recharge, especially through sinking streams, tends to produce maze caves or local mazes superimposed on branchwork caves. Through floodwater activity, anastomotic mazes form in prominently bedded aquifers, network mazes in prominently fractured aquifers, and spongework mazes in highly porous or brecciated rocks. Epikarst, network caves, and spongework caves are also produced by diffuse or dispersed infiltration into the karst aquifer, and network and spongework caves can be the product of mixing of two waters of contrasting chemistry. Ramiform caves are produced most often by rising water rich in hydrogen sulfide, which oxidizes to sulfuric acid. Deep-seated processes that help to initiate cave development include the interaction between carbonates and sulfates, which can greatly increase the solubility of dolomite, gypsum, and anhydrite, while calcite precipitates. Although tightly confined artesian conditions have long been associated with the origin of maze caves, they actually have no inherent tendency to form mazes. The slow movement of groundwater close to equilibrium with dissolved bedrock, typical of tightly confined artesian aquifers, is the least favorable setting for maze development.

Speleogenesis of the Black Hills Maze Caves, South Dakota, USA, 2000, Palmer A. N. , Palmer M. V.
Caves of the Black Hills of South Dakota, USA, are located in the Madison Limestone of Mississippian (early Carboniferous) age in a zone of diagenetic breccias and late-Mississippian paleokarst. Most of the caves are extremely complex networks with multiple stratigraphically controlled storeys. Today they are essentially hydrologic relics. Their history is as complex as the caves themselves: (1) The earliest cave openings were formed by diagenetic processes, mainly by the dissolution and reduction of sulfates. Oxidation of hydrogen sulfide produced many small and rather isolated voids lined by brecciated bedrock. (2) Late Mississippian exposure produced caves, dolines, and surface fissures, which were later filled with basal Pennsylvanian (late Carboniferous) sands and clays of the Minnelusa Formation. (3) Deposition of sedimentary strata buried these early karst features to depths of at least two kilometers. During this time, voids that had not been entirely filled by Pennsylvanian sediment were lined by a thin layer of scalenohedral calcite, and later by quartz. (4) Uplift of the Black Hills at the end of the Cretaceous Period exposed the Madison Limestone once again, allowing rapid groundwater flow through it. The earlier caves and solution pockets were enlarged at this time. (5) A thick layer of rhombohedral calcite precipitated on the cave walls, probably as the result of stagnation of groundwater caused by late Tertiary aggradation, which blocked spring openings. (6) Both before and after the calcite wall crust was deposited, deep subaerial weathering produced boxwork, with veins of calcite that had replaced earlier sulfates, as well as thick accumulations of carbonate sediment. The Tertiary cave enlargement probably involved mixing of at least two of the following water sources: artesian flow from recharge along the carbonate outcrop area, diffuse recharge through the overlying sandstone, and rising thermal water. There is evidence for all three sources, but the relative importance of each is still uncertain.

Sulfide-bearing palaeokarst deposits at Lune River Quarry, Ida Bay, Tasmania., 2001, Osborne R. A. L. , Cooper I. B.

Sulfide-bearing palaeokarst deposits at Lune River Quarry, Ida Bay, Tasmania, 2001, Osborne R. A. L. , Cooper I. B. ,
The Lune River Quarry at ida Bay. Tasmania exposes numerous palaeokarst features developed in the Ordovician Gordon Limestone. These palaeokarst features contain carbonate and siliciclastic deposits probably representing Late Devonian to early Late Carboniferous and Late Carboniferous karstification and sedimentation. Five facies of palaeokarst deposits are recognised, namely megabreccia, graded-bedded carbonate, laminated sandstone/siltstone, diamictite/quartz-lithic sandstone and coarse crystalline calcite. Pyrite, dolomite and sphalerite were emplaced in the palaeokarst deposits after the Carboniferous. These deposits are probably associated with a phase of hydrothermal cave development in Exit Cave, which adjoins the quarry. Pyrite weathering accounts for the abundance of gypsum speleothems and cave breakdown in Exit Cave

Ecological assessment and geological significance of microbial communities from Cesspool Cave, Virginia, 2001, Engel As, Porter Ml, Kinkle Bk, Kane Tc,
Microbial mats from hydrogen sulfide-rich waters and cave-wall biofilms were investigated from Cesspool Cave, Virginia, to determine community composition and potential geomicrobiological functioning of acid-producing bacteria. Rates of microbial mat chemoautotrophic productivity were estimated using [C-14]-bicarbonate incorporations and microbial heterotrophy was determined using [C-14]-leucine incubations. Chemoautotrophic fixation was measured at 30.4 12.0 ng C mg dry wt(1) h(1), whereas heterotrophic productivity was significantly less at 0.17 0.02 ng C mg dry wt(1) h(1). The carbon to nitrogen ratios of the microbial mats averaged 13.5, indicating that the mats are not a high quality food source for higher trophic levels. Ribosomal RNA-based methods were used to examine bacterial diversity in the microbial mats, revealing the presence of at least five strains of bacteria. The identity of some of the strains could be resolved to the genus Thiothrix and the Flexibacter-Cytophaga-Bacteriodes phylum, and the identity of the remaining strains was to either the Helicobacter or Thiovulum group. Two of 10 sulfur-oxidizing, chemoautotrophic pure cultures of Thiobacillus spp. (syn. Thiomonas gen. nov.) demonstrated the ability to corrode calcium carbonate, suggesting that the colonization and metabolic activity of these bacteria may be enhancing cave enlargement

The hypogenic caves: a powerful tool for the study of seeps and their environmental effects, 2002, Forti P, Galdenzi S, Sarbu Sm,
Research performed in caves has shown the existence of significant effects of gas seeps, especially CO2 and H2S, within subterranean voids. Carbon dioxide causes important corrosive effects and creates characteristic morphologies (e.g., bell-shaped domes, bubble's trails), but is not involved in the deposition of specific cave minerals. On the other hand, in carbonate environments, hydrogen sulfide when oxidized in the shallow sections of the aquifer generates important corrosion effects and is also responsible for the deposition of specific minerals of which gypsum is the most common.Studies performed in the last few years have shown that H2S seeps in caves are associated with rich and diverse biological communities, consisting of large numbers of endemic species. Stable isotope studies (carbon and nitrogen) have demonstrated that these hypogean ecosystems are entirely based on in situ production of food by chemoautotrophic microorganisms using energy resulting from the oxidation of H2S.Although located only 20 m under the surface, Movile Cave does not receive meteoric waters due to a layer of impermeable clays and loess that covers the Miocene limestone in which the cave is developed. In the Frasassi caves, where certain amounts of meteoric water seep into the limestone, the subterranean ecosystems are still isolated from the surface. As the deep sulfidic waters mix with the oxigenated meteoric waters, sulfuric acid limestone corrosion is accelerated resulting in widespread deposition of gypsum onto the cave walls.Both these caves have raised a lot of interest for biological investigations regarding the chemoautotrophically based ecosystems, demonstrating the possibility of performing such studies in environments that are easily accessible and easy to monitor compared to the deep-sea environments where the first gas seeps were discovered

Genesis of the Dogankuzu and Mortas Bauxite Deposits, Taurides, Turkey: Separation of Al, Fe, and Mn and Implications for Passive Margin Metallogeny, 2002, Ozturk Huseyin, Hein James R. , Hanilci Nurullah,
The Taurides region of Turkey is host to a number of important bauxite, Al-rich laterite, and Mn deposits. The most important bauxite deposits, Do[g]ankuzu and Morta[s], are karst-related, unconformity-type deposits in Upper Cretaceous limestone. The bottom contact of the bauxite ore is undulatory, and bauxite fills depressions and sinkholes in the footwall limestone, whereas its top surface is concordant with the hanging-wall limestone. The thickness of the bauxite varies from 1 to 40 m and consists of bohmite, hematite, pyrite, marcasite, anatase, diaspore, gypsum, kaolinite, and smectite. The strata-bound, sulfide- and sulfate-bearing, low-grade lower part of the bauxite ore bed contains pyrite pseudomorphs after hematite and is deep red in outcrop owing to supergene oxidation. The lower part of the bauxite body contains local intercalations of calcareous conglomerate that formed in fault-controlled depressions and sinkholes. Bauxite ore is overlain by fine-grained Fe sulfide-bearing and calcareous claystone and argillaceous limestone, which are in turn overlain by massive, compact limestone of Santonian age. That 50-m-thick limestone is in turn overlain by well-bedded bioclastic limestone of Campanian or Maastrichtian age, rich with rudist fossils. Fracture fillings in the bauxite orebody are up to 1 m thick and consist of bluish-gray-green pyrite and marcasite (20%) with bohmite, diaspore, and anatase. These sulfide veins crosscut and offset the strata-bound sulfide zones. Sulfur for the sulfides was derived from the bacterial reduction of seawater sulfate, and Fe was derived from alteration of oxides in the bauxite. Iron sulfides do not occur within either the immediately underlying or overlying limestone. The platform limestone and shale that host the bauxite deposits formed at a passive margin of the Tethys Ocean. Extensive vegetation developed on land as the result of a humid climate, thereby creating thick and acidic soils and enhancing the transport of large amounts of organic matter to the ocean. Alteration of the organic matter provided CO2 that contributed to formation of a relatively 12C-rich marine footwall limestone. Relative sea-level fall resulted from strike-slip faulting associated with closure of the ocean and local uplift of the passive margin. That uplift resulted in karstification and bauxite formation in topographic lows, as represented by the Do[g]ankuzu and Morta[s] deposits. During stage 1 of bauxite formation, Al, Fe, Mn, and Ti were mobilized from deeply weathered aluminosilicate parent rock under acidic conditions and accumulated as hydroxides at the limestone surface owing to an increase in pH. During stage 2, Al, Fe, and Ti oxides and clays from the incipient bauxite (bauxitic soil) were transported as detrital phases and accumulated in the fault-controlled depressions and sinkholes. During stage 3, the bauxitic material was concentrated by repeated desilicification, which resulted in the transport of Si and Mn to the ocean through a well-developed karst drainage system. The transported Mn was deposited in offshore muds as Mn carbonates. The sulfides also formed in stage 3 during early diagenesis. Transgression into the foreland basin resulted from shortening of the ocean basin and nappe emplacement during the latest Cretaceous. During that time bioclastic limestone was deposited on the nappe ramp, which overlapped bauxite accumulation

Carbonate Speleothems in the Dry, Inneralpine Vinschgau Valley, Northernmost Italy: Witnesses of Changes in Climate and Hydrology Since the Last Glacial Maximum, 2002, Spotl C. , Unterwurzacher M. , Mangini A. , Longstaffe F. J. ,
An interesting association of slope breccia, inactive and active tufa deposits, and speleothems is present in the central Vinschgau Valley, Italy. The occurrence of abundant carbonate cements in fractures and voids of crystalline basement rocks is unexpected considering the fact that this valley is among the driest spots in the entire Alps. Low annual precipitation of 440-530 mm coupled with frequent wind give rise to a semiarid climate and steppe vegetation along the south-facing slopes of the valley. Springs in this area are mostly supersaturated with respect to calcite, and carbonate precipitation occurs locally as tufas and, less well known because of lack of accessibility, as speleothems in the shallow subsurface. The majority of the tufa deposits and speleothems, however, are fossil. Speleothems are composed of low-Mg calcite and calcite-aragonite, respectively. Delicate growth textures including presumable annual lamination caused by pronounced changes in fluorescence intensity are preserved in both calcite and aragonite. Most calcite is a primary precipitate, but small amounts of secondary calcite replacing aragonite are common in most aragonite-bearing samples. The highly radiogenic Sr isotope composition, as well as high concentrations of U, Fe, Sr, and Mg, indicate that the groundwater from which these carbonates precipitated experienced intensive interaction with the host crystalline rocks. The very low tritium concentrations and the lack of a seasonal O isotope variation in modern spring waters, as well as their rather constant hydrochemical composition, also support this suggestion. S isotope data for dissolved sulfate and Ca and Mg sulfate precipitates indicate a sulfide source, i.e., oxidation of sulfide ore minerals in the aquifer, resulting in elevated sulfate and Fe concentrations. Th/U dating of speleothem samples using thermal ionization mass spectrometry yielded ages between 13,710 and 378 yr BP, with most ages falling in the early to middle Holocene. Although no isotopic dates are available for the tufa deposits, field evidence strongly suggests that speleothems, tufa deposits, and carbonate cements in the slope breccia were closely related. We therefore interpret the existence of these terrestrial carbonates as evidence of changes in climate since the middle Holocene. Their presence suggests a higher annual rainfall during the first half of the Holocene, possibly because of enhanced moisture transport from the Mediterranean

Gypsum deposits in the Frasassi Caves, central Italy, 2003, Galdenzi, S. , Maruoka, T.
The Frasassi Caves are hypogenic caves in central Italy, where H2S-rich groundwater flows in the lowest cave level. Near the water table, the H2S is converted to sulfuric acid by biotic and abiotic processes, which have enhanced cave development. The sulfate generally deposits above the water table as a replacement gypsum crust coating limestone walls or as large gypsum crystals. Although the oxidation of sulfide also occurs below the water table, sulfate saturation is not achieved, therefore, sulfate does not precipitate below the water table. In the upper dry levels of the cave, three main types of ancient gypsum deposits occurs: (1) replacement crusts, similar to the presently forming deposits of the active zone, (2) microcrystalline large and thick floor deposits, and (3) euhedral crystals inside mud. The study of the depositional setting and the analysis of sulfur isotopes in the gypsum and groundwater clearly demonstrate that all the sampled gypsum in the cave formed by H2S oxidation above the water table. Some fraction of small sulfur isotopic differences between H2S in the water and gypsum can be explained by isotopic fractionation during abiotic and/or biotic oxidation of H2S.

Patterns of dissolutional porosity in carbonate rocks, 2003, Palmer, A. N.

This paper reviews the hydrochemical processes that determine the patterns of caves and other solutional features within carbonate rocks. The model presented relies on the functional relationships expressed by chemical mass balances, flow equations, and kinetic expressions for dissolution rate. Although it shares many aspects of purely conceptual models and is backed by field evidence, its quantitative basis places it into the realm of analytical models.
The conclusions merely summarize earlier work (mainly Palmer, 1981, 1991). Solutional enlargement of caves and other karst features is highly selective in water that is close to equilibrium with dissolved carbonate minerals, enlarging only the most favorable openings – i.e. those that transmit the greatest discharge. This is characteristic of long flow paths within a typical karst aquifer. In contrast, solutional enlargement will be rather uniform along many competing flow paths where there is (1) high discharge, (2) sustained steep hydraulic gradients, (3) short flow paths, or (4) local renewal of aggressiveness by mixing, oxidation of sulfides, etc. These conditions produce maze caves and epikarstic networks. In general, this condition prevails if Q/rL > 0.001 cm/sec (tubes), or /bL > 0.001 cm/sec (fissures), where Q = discharge, r = tube radius, b = long dimension of fissure cross section, and L = distance of flow from where the initial aggressive solution comes in contact with the carbonate rock.

Filamentous 'Epsilonproteobacteria' dominate microbial mats from sulfidic cave springs, 2003, Engel As, Lee N, Porter Ml, Stern La, Bennett Pc, Wagner M,
Hydrogen sulfide-rich groundwater discharges from springs into Lower Kane Cave, Wyoming, where microbial mats dominated by filamentous morphotypes are found. The full-cycle rRNA approach, including 16S rRNA gene retrieval and fluorescence in situ hybridization (FISH), was used to identify these filaments. The majority of the obtained 16S rRNA gene clones from the mats were affiliated with the 'Epsilonproteobacteria' and formed two distinct clusters, designated LKC group I and LKC group II, within this class. Group I was closely related to uncultured environmental clones from petroleum-contaminated groundwater, sulfidic springs, and sulfidic caves (97 to 99% sequence similarity), while group II formed a novel clade moderately related to deep-sea hydrothermal vent symbionts (90 to 94% sequence similarity). FISH with newly designed probes for both groups specifically stained filamentous bacteria within the mats. FISH-based quantification of the two filament groups in six different microbial mat samples from Lower Kane Cave showed that LKC group II dominated five of the six mat communities. This study further expands our perceptions of the diversity and geographic distribution of 'Epsilonproteobacteria' in extreme environments and demonstrates their biogeochemical importance in subterranean ecosystems

Delineating the karstic flow system in the upper Lost River drainage basin, south central Indiana: using sulphate and delta S-34(SO4) as tracers, 2003, Lee E. S. , Krothe N. C. ,
A karstic flow system in the upper Lost River drainage basin in south central Indiana, USA, was investigated using SO4 concentration and delta(34)S(SO4) as tracers. The flow system was characterized as vadose flow and phreatic diffuse flow. Vadose-flow samples were collected from 7 epikarstic outlets after storm events. Phreatic diffuse flow samples were collected from the Orangeville Rise, the major emergence point for the drainage basin, during the base flow periods. Discharge from the Orangeville Rise was constant during the base flow periods but showed large variations in flow rate (0.3-11.7 m(3)/S), SO4 concentration (11-220 mg/l), and delta(34)S(SO4), ( 5.2 to 15.0parts per thousand) after storm events, due to the mixing of rain, vadose flow, and phreatic diffuse flow in the conduits that feed the Orangeville Rise. Sulphate concentrations and delta(34)S(SO4), were unique in vadose flow (S-SO4: 13-24 mg/l; delta(34)S(SO4),: 1.9 to 3.8parts per thousand) and phreatic diffuse flow (SO4: 220 mg/l; delta(34)S(SO4),: 15.0parts per thousand). Mean SO4 concentration of rainwater in the study area was measured as 1.8 mg/l. Using a 3-component mixing model for water in the karstic conduits, the mixing ratios of rain (16.5%), vadose flow (58.5%), and phreatic diffuse flow (25.0%) components were calculated in the Orangeville Rise discharge. These mixing ratios attained using SO4 concentration as a tracer indicated the important role of the vadose zone as a water storage area in karst aquifers. (C) 2002 Published by Elsevier Science Ltd

The Shaimerden Supergene Zinc Deposit, Kazakhstan: A Preliminary Examination, 2003, 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

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