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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. ...

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. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
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 dry cave is a cave without a running stream [10]. see also dead cave.?

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Chemistry and Karst, White, William B.
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Geochemical and mineralogical fingerprints to distinguish the exploited ferruginous mineralisations of Grotta della Monaca (Calabria, Italy), Dimuccio, L.A.; Rodrigues, N.; Larocca, F.; Pratas, J.; Amado, A.M.; Batista de Carvalho, L.A.
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
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Your search for fault zones (Keyword) returned 27 results for the whole karstbase:
Showing 1 to 15 of 27
DIAGENESIS AND MINERALIZATION PROCESSES IN DEVONIAN CARBONATE ROCKS OF THE SIDING-GUDAN LEAD-ZINC MINERAL SUBDISTRICT, GUANGXI, SOUTHWEST CHINA, 1991, Schneider W. , Geng A. Q. , Liu X. Z. ,
The lead-zinc ore deposits of the Siding-Gudan mineral subdistrict Guangxi are part of the large Nanling district of South China, and hosted in Devonian carbonate rocks. The ore bodies occur significantly along main faults and fault zones, and concentrate up to 300 meters above the Cambrian/Devonian unconformity. Connected with hydrothermal karst, size and volume of the ore bodies increase in proximity to this unconformity. Moving from the unaffected host rocks to the center of the ore bodies, four zones can be discriminated by the mineral assemblage (pyrite, sphalerite, galena) as well as by the degree of ordering, Ca/Mg, and Fe/Mn ratios of different dolomites. Homogenization temperatures range from 80-100-degrees-C (Presqu'ile dolomite) to 230-260-degrees-C (massive sphalerite). The sulfides reveal delta-S-34 = -20 to parts per thousand, and fluid inclusions display a salinity of 5-12 wt % equivalent NaCl. The diagenetic and hydrothermal history is similar to that of classic Mississippi Valley Type (MVT) sulfide mineral deposits as, for example, Pine Point in Canada. Mineralization and remobilization of the sulfides took place during a wide time span from late Paleozoic through Mesozoic. Both processes are considered as an interaction of saline basinal brines ascended from the adjoining dewatering trough, and magmatic-hydrothermal fluids of several magmatic-tectonic events

CHEMICAL-REACTION PATH MODELING OF ORE DEPOSITION IN MISSISSIPPI VALLEY-TYPE PB-ZN DEPOSITS OF THE OZARK REGION UNITED-STATES MIDCONTINENT, 1994, Plumlee G. S. , Leach D. L. , Hofstra A. H. , Landis G. P. , Rowan E. L. , Viets J. G. ,
The Ozark region of the U.S. midcontinent is host to a number of Mississippi Valley-type districts, including the world-class Viburnum Trend, Old Lead Belt, and Tri-State districts and the smaller Southeast Missouri barite, Northern Arkansas, and Central Missouri districts. There is increasing evidence that the Ozark Mississippi Valley-type districts formed locally within a large, interconnected hydrothermal system that also produced broad fringing areas of trace mineralization, extensive subtle hydrothermal alteration, broad thermal anomalies, and regional deposition of hydrothermal dolomite cement. The fluid drive was provided by gravity flow accompanying uplift of foreland thrust belts during the Late Pennsylvanian to Early Permian Ouachita orogeny. In this study, we use chemical speciation and reaction path calculations, based on quantitative chemical analyses of fluid inclusions, to constrain likely hydrothermal brine compositions and to determine which precipitation mechanisms are consistent with the hydrothermal mineral assemblages observed regionally and locally within each Mississippi Valley-type district in the Ozark region. Deposition of the regional hydrothermal dolomite cement with trace sulfides likely occurred in response to near-isothermal effervescence of CO2 from basinal brines as they migrated to shallower crustal levels and lower confining pressures. In contrast, our calculations indicate that no one depositional process can reproduce the mineral assemblages and proportions of minerals observed in each Ozark ore district; rather, individual districts require specific depositional mechanisms that reflect the local host-rock composition, structural setting, and hydrology. Both the Northern Arkansas and Tri-State districts are localized by normal faults that likely allowed brines to rise from deeper Cambrian-Ordovician dolostone aquifers into shallower carbonate sequences dominated by limestones. In the Northern Arkansas district, jasperoid preferentially replaced limestones in the mixed dolostone-limestone sedimentary packages. Modeling results indicate that the ore and alteration assemblages in the Tri-State and Northern Arkansas districts resulted from the flow of initially dolomite-saturated brines into cooler limestones. Adjacent to fluid conduits where water/rock ratios were the highest, the limestone was replaced by dolomite. As the fluids moved outward into cooler limestone, jasperoid and sulfide replaced limestone. Isothermal boiling of the ore fluids may have produced open-space filling of hydrothermal dolomite with minor sulfides in breccia and fault zones. Local mixing of the regional brine with locally derived sulfur undoubtedly played a role in the development of sulfide-rich ore runs. Sulfide ores of the Central Missouri district are largely open-space filling of sphalerite plus minor galena in dolostone karst features localized along a broad anticline. Hydrothermal solution collapse during ore deposition was a minor process, indicating dolomite was slightly undersaturated during ore deposition. No silicification and only minor hydrothermal dolomite is present in the ore deposits. The reaction path that best explains the features of the Central Missouri sulfide deposits is the near-isothermal mixing of two dolomite-saturated fluids with different H2S and metal contents. Paleokarst features may have allowed the regional brine to rise stratigraphically and mix with locally derived, H2S-rich fluids

REMOTE-SENSING OF TECTONIC FABRIC CONTROLLING GROUNDWATER-FLOW IN DINARIC KARST, 1995, Kresic N. ,
Geological and hydrogeological remote sensing techniques can be applied very favorably to Dinaric karst in the Balkans, a well-known reference area for studies of karst phenomena. The elements that make karst terrain of the Dinarides suitable for remote sensing are geomorphologic characteristics, in particular the specific surface drainage and karst forms, the varying vegetation that most often reflects the existence of different geologic formations on the surface, and distinct tectonic features. Some of the world's largest springs, ponors (sinks), and dolines are controlled by fractures visible on both satellite images and aerial photographs. Lineaments represent fault zones, systems of close faults with similar strike, or large individual faults which all are young or show recently renewed activity. Their neotectonic character and major importance for karst groundwater flow are confirmed by numerous field investigations including water tracing, geophysical research, and drilling

Sedimentology and Paleomagnetism of Sediments, Kartchner Caverns, Arizona, 1999, Hill, C. A.
Clastic deposits in Kartchner Caverns consist of coarse deposits (breakdown, pebble gravel and micaceous sand) and fine-grained deposits (fault gouge and blocky clay). The coarse deposits are all related to the vadose history of the cave, while the fine-grained deposits are related to the phreatic history of the cave and, probably, to the beginning of vadose conditions. The illite clay in fault zones was possibly derived from the underlying Pinal Schist. The clay mineral rectorite is most likely a hydrothermal alteration of illite within the faults prior to the dissolution of the cave. The blocky clay unit is autochthonous sediment that was at least partially derived from residual fault gouge clay at the time of cave dissolution. The pebble gravels were deposited during different flood events in different parts of the cave, with a lateral fining of micaceous sand in back-wash areas. The blocky clay, pebble gravel, and micaceous sand are all paleomagnetically normal and date from the Brunhes/Matuyama normal (<~780 Ka). The clay mineral nontronite probably reconstituted from residual illite/rectorite under high pH, low Eh flood-water conditions within the cave environment

Influence of tectonics and neotectonics on the morphogenesis of the peak karst of Halong Bay, Vietnam, 1999, Fenart P, Cat Nn, Drogue C, Van Canh D, Pistre S,
In northeast Vietnam, the karst of Halong Bay is characterized by very active neotectonics. The directional distribution of fracturing of the calcareous rocks is characterized by the influence of two major fault zones: the Red River fault zone (N140) and the Tan-Lu fault zone (N050). Karst development was favoured by intense fracturing, according to these two major directions, and reactived during recent tectonics by a compressional regime with sigma 1 N070, followed by an extensional regimes with ol near to EW that led to significant vertical movement. These tectonics, coupled with intense erasion, led to genesis and evolution of the spectacular morphology of this peak karst. (C) Elsevier, Paris

Karstification associated with groundwater circulation through the Redwall artesian aquifer, Grand Canyon, Arizona, USA, 2000, Huntoon P. W.
The karstified Redwall artesian aquifer discharges significant quantities of water to a small number of large springs in the Marble and Grand canyons of Arizona, U.S.A. The locations of the springs are topographically controlled, being situated on the flanks of regional structural depressions at locations where the depressions have been dissected by the canyons. The springs serve as the lowest potentiometric spill points for the aquifer. Modern caves behind the springs appear to be adjusted to the hydraulic boundary conditions governing circulation through the aquifer. These caves appear to be organized parallel to modern hydraulic gradients and are thus fairly independent of preexisting dissolution-enhanced fracture permeability. This indicates that sufficient time has elapsed since the modern circulation system boundaries became established for the flow regime to have created optimally oriented karstic permeability pathways. Dry remnant caves occur in dewatered sections of the Redwall aquifer which obviously predate dissection of the aquifer by the Colorado River. In contrast to the active caves, the dry caves are characterized by keyhole and slot passageways that are predominantly localized along joints and normal faults. The fractures date largely from late Tertiary extensional tectonism. These older caves are interpreted to be remnants of dissolution conduits in what was a more widespread regional Redwall artesian aquifer prior to incision of the Grand Canyon. Recharge to the Redwall aquifer takes place primarily as vertical circulation in normal fault zones where the faults have propagated upward through the overlying Supai confining layer. The water enters the faults directly from the land surface or as leakage from shallower aquifers that drain to the faults.

Geographic information systems analysis of geologic controls on the distribution on dolines in the Ozarks of south-central Missouri, USA, 2000, 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.


Karst characteristics of thrust contact limestone-dolomite near Predjama, 2001, Č, Ar Jož, E, Š, Ebela Stanka

With detailed lithological and tectonic-structural mapping at the scale 1:5000 we studied the area near Bukovje NE from Predjama. In the studied area and further towards the NE we can follow a strong thrust contact between Upper Cretaceous limestones of Snežnik thrust sheet over which Upper Triassic Norian-Rhaetian dolomite of Hrušica thrust sheet is overthrust. The thrust is cut by systems of dextral faults with expressed vertical component. Beneath the studied area underground passages of Predjama cave can be found; they are developed in limestones as in dolomites. Dolines in Upper Cretaceous limestone are uniformly arranged and are in structural-genetic view broken (D), near-fault (E) or fault (F). Along the thrust edge we have contact dolines (G) in dolomite. The rest of the dolines on dolomite are connected to differently broken rocks in fault zones and are called reproduced fault-broken dolines / HF(D)do /. For described karst features along thrust contact we suggest the name contact karst on dolomite along thrust.


Tracer Study on the Tectonic Controll of the Drainage System in the Contact Karst Zone of Lake Voralp (Swiss Alps), 2001, Ross Janhenning, Rieg Alfred, Leibundgut Chris

Lake Voralp is a small karst lake, dammed up by a Pleistocene rockslide and without any surface drainage. A dye tracer test under flood conditions shows a widespread drainage system to remote springs and direct afflux to the porous aquifer of the Rhine Valley. These karstwater passages are leading through nonkarstified flysch and a marly layer. Both layers are lithologically rather impermeable and karstwater passages through these layers indicates water leading fault zones. Properties of the drainage patterns strongly depend on the hydrological situation.


The Padaeng Supergene Nonsulfide Zinc Deposit, Mae Sod, Thailand, 2003, Reynolds Neal A. , Chisnall Tony W. , Kaewsang Kriangsak, Keesaneyabutr Chanan, Taksavasu Taksorn,
The Padaeng deposit near Mae Sod in western Thailand was the first supergene nonsulfide zinc deposit in the world to be developed as a large modern mining operation. The mine and associated zinc smelter, operated by Padaeng Industry Public Company Ltd. since 1984, went into production with reserves of 4.59 Mt at a grade of 28.9 percent zinc with a 10 percent zinc cutoff. Current resources are 5.14 Mt at a grade of 12.0 percent zinc with a 3 percent zinc cutoff. The Padaeng deposit is hosted by a mixed carbonate-clastic sequence of Middle Jurassic age. The deposit occurs in the hanging wall of the Padaeng fault, a major northwest-trending structure that was active through Cretaceous and Tertiary tectonism and uplift. Nonsulfide zinc ore comprises dominant hemimorphite with minor smithsonite and hydrozincite. Strata-bound ore zones occur within a northwest-dipping, deeply weathered, dolomitic sandstone; steeply dipping and irregular karstic zones in underlying massive, silty dolomite are controlled by north-trending fracture zones. Sulfide zinc-lead mineralization of Mississippi Valley type occured extensively in the vicinity of the Padaeng mine, most notably the small resources at Pha De and Hua Lon. Mineral deposits are typically sphalerite rich with minor galena and pyrite, forming small-scale open-space fillings, veins, and replacements within hydrothermal dolomite. Mineralization is dominantly strata bound within a horizon of intense hydrothermal dolomitization that forms the stratigraphic hanging wall to the nonsulfide ore zones at Padaeng. The only significant sulfide at the Padaeng mine is within this unit. Only trace sulfide occurs peripheral to, or down dip of, strata-bound or steeply dipping, nonsulfide orebodies. Sulfide mineralization is believed to have accompanied Cretaceous uplift and deformation, related to the onset of oblique subduction beneath the western margin of the Shan-Thai terrane. The nonsulfide deposit is believed to have formed when a substantial body of sulfide ore was uplifted on the margin of the Mae Sod Tertiary intermontane basin, commencing in the middle to late Miocene. Zinc-bearing acidic supergene fluids, generated by oxidation of the precursor sulfide body, reacted with carbonate in the underlying stratigraphic section to precipitate hemimorphite and smithsonite. Fluids were channeled by permeable dolomitic sandstones and by steep fracture and fault zones. Acidic fluids promoted deep weathering and karst formation, allowing mineralization to extend down dip in sandstone units for at least 150 m and vertically for a similar distance in steep structural zones. Transport of zinc out of the precursor sulfide body was facilitated by a falling water table, owing to uplift of the Padaeng fault block and a change from wet tropical to monsoonal or semiarid climatic conditions. There is no evidence for significant in situ replacement of sulfide deposits, and the leached remnants of the precursor sulfide body have been removed by erosion. The supergene process of dissolution and reprecipitation of zinc in the host rocks increased zinc grades and separation of zinc from lead, producing an economically attractive deposit. Successful exploration for this type of deposit requires a good understanding of the controls on primary sulfide mineralization and a good knowledge of local neotectonism, uplift history, hydrogeology, climatic evolution, and weathering history

Chalk engineering geology - Channel Tunnel Rail Link and North Downs Tunnel, 2003, Warren C. D. , Mortimore R. N. ,
Agreat part of the Channel Tunnel Rail Link (CTRL) is constructed through the Chalk and the ground investigation for the CTRL has yielded a mass of new information on allaspects of the Chalk. A precise bed by bed lithostratigraphy obtained from cored boreholes has aided engineering description, classification, decision making on design of machines and construction methods/specifications. Correlation of Chalk marker beds between boreholes drilled for the tunnels beneath London illustrated the influence of sub-Tertiary erosion and of faulting onpreservation of different stratigraphic levels in the Chalk. These different stratigraphic levels affect materials through which the tunnels will be constructed andconsequently tunnel vertical alignment or choice of construction method. The marker bed stratigraphy in the Thames Tunnel boreholes has enabled the same stratigraphic levels to be identified in local quarries and detailed analyses to be carried out for the design of Tunnel Boring Machines. Using individual marker beds, a detailed ground profile was constructed for the North Downs Tunnel which allowed fault zones to be predicted accurately and the different rock mass character of the Chalk formations to be delimited for numerical modelling, design zones and construction monitoring. The project also provided the opportunity to evaluate the CIRIA Chalk Grading scheme

Karst geology and engineering treatment in the Geheyan Project on the Qingjiang River, China, 2004, Xu Ruichun, Yan Fuzhang,
The Geheyan Hydropower Project is located in a highly karstified limestone area. The Shilongdong limestone of the foundation bedrock is strongly karstified. Over 600 karst caves of different sizes were discovered in the project area, with a total volume of more than 60,000 m3. Faults parallel to the river are quite developed and karstification is intensified along the faults and their intersections. Exploration adits following the fault zones show a linear karstification ratio of 50%. Therefore, the potential karst leakage under the dam foundation and around both dam abutments is potentially problematic. Thanks to a proper investigation program and a large amount of geological investigations and analysis the karst conditions and major karst zones in the dam site had been identified before the construction commenced. Accordingly, the optimum grouting route was chosen and appropriate seepage control measures were adopted. During the construction, the pre-construction investigation results were well confirmed. Up to now, the project has been in good operation for nine years and the engineering treatment are proved to be very effective

Dissolution of limestone fractures by cooling waters: Early development of hypogene karst systems, 2005, Andre Bj, Rajaram H,

[1] Fracture dissolution in the early stages of karstification under hypogene conditions is investigated using a coupled numerical model of fluid flow, heat transfer, and reactive transport. Dissolution of calcite in the H2O-CO2-CaCO3 system along a cooling flow path is investigated using both equilibrium and kinetic models. During the very early stages of fracture growth, there is a positive feedback between flow, heat transfer, and dissolution. In this stage the dissolution rate is largely controlled by the retrograde solubility of calcite, and aperture growth is relatively uniform along the fracture length. There is a period of slow continuous increase in the mass flow rate through the fracture, which is followed by an abrupt rapid increase. We refer to the time when this rapid increase occurs as the maturation time. As the flow rate continues to increase after maturation, forced convective effects lead to higher fluid temperatures in the fracture, resulting in a negative feedback that slows the rate of fracture growth. The behavior of aperture growth before the maturation time can be described by a simple ordinary differential equation. The solution of this differential equation provides an estimate of the maturation time, in terms of the initial aperture, hydraulic and thermal gradients, and the change in solubility with temperature. The behavior before maturation in two-dimensional variable aperture fractures is investigated using a simplified model. The maturation time is shown to decrease with the degree of aperture variability due to highly selective growth along preferential flow paths


Discrimination of meteoric karst breccias from tectono-thermobaric breccias, 2005, Smith Langhorne B. , Palmer Arthur
Tectono-thermobaric breccias and associated hydrothermal dolomite reservoirs, such as those in the Trenton-Black River play, represent a major remaining resource in North America. Tectono-thermobaric breccias must be differentiated from paleokarst breccias for sound exploration and development decisions. Paleokarst breccias and collapsed meteoric caves are genetically related to sequence boundaries. Many have non-carbonate detrital matrix with vestiges of calcite speleothems. Perching on low-permeability strata is common. Modern meteoric caves are far more common in limestone than dolomite, typically <10 meters wide, and limited to areas of local topographic relief and discharge into a surface drainage system. Cavernous porosity is irregularly distributed and rarely more than 5% of the total rock volume. Ancient collapsed caves should show evidence for these characteristics. Tectono-thermobaric breccias form where space is created in active fault zones. Thermobaric (high-pressure, high-temperature) fluids flow up the active faults, enlarge fractures and precipitate minerals such as saddle dolomite, calcite and sulfides between clasts. Breccias follow fault trends, can be up to hundreds of meters wide, and are commonly concentrated beneath sealing shales or argillaceous limestones. These breccias can occur in limestone or dolomite but are commonly associated with hydrothermal matrix dolomitization. High permeability and porosity can be preserved between partially cemented clasts and in linked vugs, fractures and matrix. Tectono-thermobaric breccias form mainly in previously unbrecciated strata, but they may serendipitously intersect earlier meteoric karst. Tectono-thermobaric brecciated reservoirs commonly occur around wrench faults identifiable on seismic data. These reservoirs commonly do not require structural closure, so many potential targets remain undrilled. Tectono-thermobaric carbonate breccias also host many of the world's sulfide ore deposits. Many brecciated reservoirs and ore deposits that have been previously interpreted as meteoric karst may in fact be tectono-thermobaric in origin.

Hydrochemic characteristics and tectonic situation of selected springs in central and NW Yunnan province, China., 2006, ebela S. , Kogovek J.
The Province lies on the eastern rim of the collision zone between the Indian plate and Eurasia. This region is characterized by complex Cenozoic structures and active seismotectonics. In the year 2004 the areas north from Kunming and the NW part of were studied. The measurements of the temperature, conductivity and the analyses of carbonate, phosphate and nitrate were performed in Quinglongtan spring and in the accumulation lake that is situated lower than the spring. The springs are situated in the wider zone of the Xiaojiang fault along which left horizontal movements are taking place. Along the wider zone of the Zhongdian fault between the town of Zhongdian and the River on the south there are more springs. Tiansheng Qiao (T = 57.5C) and Xiageiwenquan (T = 48,3 ? 66.8C) are thermal springs along which tufa is deposited. The Baishuitai spring has high mineralization and lower temperature (T = 11.1 ? 13.3C) and deposits calcium carbonate in the form of gours. All studied springs are connected with active fault zones. The studied areas mostly represent the contact areas between carbonate and non-carbonate rocks.

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