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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 skylight is a hole in the roof of a cave passage through to the ground surface. it may be an inlet shaft, a section of collapse or a breach due to surface lowering [9].?

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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 naica (Keyword) returned 14 results for the whole karstbase:
Carbon isotope exchange rate of DIC in karst groundwater, 2003, Gonfiantini R. , Zuppi G. M. ,
The kinetics of isotopic exchange between dissolved inorganic carbon (DIC) of groundwater and calcite of the matrix of karst aquifers of Cyrenaica, Libya, can, be deduced from C-13 and C-14 data. The aquifers are mostly confined, and the majority of the wells do not show any occurrence of modem recharge: in 1976-1980, in fact, the tritium content was below 1 tritium unit (TU) in most sites. Assuming that the isotopic exchange takes place through a first order reaction such as 14 C radioactive decay, it can be shown that a linear correlation occurs between lnA and ln(delta(M) - delta - epsilon(p)), where A is the C-14 activity, delta(M) and delta are the C-13 contents of matrix calcite and DIC, respectively, and epsilon(p) is the C-13 enrichment in CaCO3 precipitation. The slope of the correlation provides the half-life of the isotopic exchange process. For Cyrenaica karst groundwater, a half-life of about 11,000 years is obtained, i.e. about double that of C-14 radioactive decay. The isotopic exchange kinetics also depends on the ratio between groundwater volume and the calcite surface exposed to the exchange process. Thus, other aquifers will show different exchange half-life values. The Cretaceous chalk aquifers of the Paris Basin, France and Lagerdorf, Germany give a half-life of about 4000 years, much shorter than that of Cyrenaica, which may be due to the high porosity, i.e. to the large surface available for the isotope exchange process. The Berkshire Chalk aquifer, UK, gives a half-life of about 10,000 years. Much higher half-lives, above 20,000 years, are obtained for two sandy aquifers in Flevoland, The Netherlands, and Texas, USA, which could be explained by the low CaCO3 content of the aquifer matrix. The highest half-life value, about 40,000 years, is obtained in an artesian limestone aquifer in Florida, USA. (C) 2002 Elsevier Science B.V. All rights reserved

Sails: a new gypsum speleothem from Naica, Chihuahua, Mexico., 2007, Forti Paolo, Bernabei Tullio, Villasuso Roberto
The caves of Naica (Chihuahua, Mexico) are perhaps the most famous mine caves of the world due to the presence of gigantic gypsum crystals. Nevertheless, very little research has been carried out on this karst area until now. A multidisciplinary investigation started in 2006 with the aim not only to define the genesis and the age of the Naica gypsum crystals, but also on other scientific aspects of these caves. This paper describes a completely new type of gypsum speleothem: the sails, observed only inside the Cueva de las Velas, one of the caves of the Naica system. This speleothem consists of extremely thin, elongated skeleton crystals that have grown epitaxially only on the tips of the gypsum crystals pointing upward. The genesis of sails is strictly related to the environmental conditions set up inside the cave just after the artificial lowering of the groundwater by mine dewatering (less than 20 yr ago). In a few years sail speleothems will disappear entirely and therefore this study is fundamental to preserve at least the memory of them.

Sails: a new gypsum speleothem from Naica, Chihuahua, Mexico, 2007, Forti Paolo, Bernabei Tullio And Villasuso Roberto
The caves of Naica (Chihuahua, Mexico) are perhaps the most famous mine caves of the world due to the presence of gigantic gypsum crystals. Nevertheless, very little research has been carried out on this karst area until now. A multidisciplinary investigation started in 2006 with the aim not only to define the genesis and the age of the Naica gypsum crystals, but also on other scientific aspects of these caves. This paper describes a completely new type of gypsum speleothem: the sails, observed only inside the Cueva de las Velas, one of the caves of the Naica system. This speleothem consists of extremely thin, elongated skeleton crystals that have grown epitaxially only on the tips of the gypsum crystals pointing upward. The genesis of sails is strictly related to the environmental conditions set up inside the cave just after the artificial lowering of the groundwater by mine dewatering (less than 20 yr ago). In a few years sail speleothems will disappear entirely and therefore this study is fundamental to preserve at least the memory of them.

THE MINERALOGICAL STUDY ON THE CUEVA DE LAS VELAS (NAICA, MEXICO), 2007, Forti P. , Galli E. , Rossi A.

The Cueva de las Velas is the last cave unveiled at -290 level within the Naica Mine; the cavity has been intercepted by a mine gallery at the beginning of 2005. One of its peculiarities is the widespread thick deposits of diagenetic minerals deposited over the cave walls before the beginning of the evolution of the giant gypsum crystals. These deposits consist of complex, often scarcely crystalline iron-manganese-lead oxides-hydroxides, but carbonates, sulphates and silicates are also present. Other minerals, mainly sulphates, started developing just after this area of the mine was dewatered some 20 years ago. Presently 17 different minerals have been observed, 5 of which (orientite, starkeyite, szmolnokite, szmikite and woodruffite) are completely new for the cavern environment. The study of these minerals, together with the presence of a completely new type of gypsum crystals, allowed to improve the knowledge on the speleogenetic evolution of this cave, which seems to be by far more complex than that of the other cavity of the -290 level. Its complexity is reflected by the activity of a larger number of different speleogenetic mechanisms. Among them are worth of mention the thermal corrosion/dissolution, the anhydrite- gypsum disequilibrium, the acid aggression, and the capillary migration and evaporation.


Uranium-series dating of gypsum speleothems: methodology and examples, 2010, Sanna L. , Saez F. , Simonsen S. , Constantin S. , Calaforra J. M. , Forti P. , Lauritzen S. E.
The analytical problems of dating gypsum speleothems with the U-series technique are reviewed. Gypsum speleothems are, in general, very low in U content, challenging the limits of detection methods. Various approaches to dissolving gypsum and isolation of actinides from the matrix include ion-pairing dissolution with magnesium salts and using nitric acid. The most precise dating technique is Thermal Ionization Mass Spectrometry (TIMS), combined with Fe(OH)3 scavenging and anionic exchange chromatography. Less satisfactory, but much quicker, is direct retention of actinides from HNO3 by means of TRU resin and MC-ICP-MS detection. We have tested these methods on gypsum speleothems from the Sorbas karst in Spain and from the Naica caves in Mexico.

Uranium-series dating of gypsum speleothems: methodology and examples, 2010, Sanna L. , Saez F. , Simonsen S. , Constantin S. , Calaforra J. M. , Forti P. , Lauritzen S. E.

The analytical problems of dating gypsum speleothems with the U-series technique are reviewed. Gypsum speleothems are, in general, very low in U content, challenging the limits of detection methods. Various approaches to dissolving gypsum and isolation of actinides from the matrix include ion-pairing dissolution with magnesium salts and using nitric acid. The most precise dating technique is Thermal Ionization Mass Spectrometry (TIMS), combined with Fe(OH)3 scavenging and anionic exchange chromatography. Less satisfactory, but much quicker, is direct retention of actinides from HNO3 by means of TRU resin and MC-ICP-MS detection. We have tested these methods on gypsum speleothems from the Sorbas karst in Spain and from the Naica caves in Mexico.


Preliminary U/Th dating and the evolution of gypsum crystals in Naica caves (Mexico), 2011, Sanna Laura, Forti Paolo, Lauritzen Steinerik

The origin and the evolution of giant selenite crystals in Naica caves, together with the understanding of their growth mechanisms, is one of the aims of the international multidisciplinary research, called the “Naica Project”. In this context, the exact timing of when the gypsum nucleation started and whether its growth has been constant over time, have been investigated. The preliminary data obtained with the U–Th disequilibrium method show significant differences in ages for gypsum (between 191 ± 13 kyr for one of the Ojo de la Reina cave crystals and 57 ± 1.7 kyr for the base of Espadas cave’s spar) and have produced a coarse chronological interval of growth. The crystal depositional rates vary from 0.56 to 1.22 mm/kyr, in excellent agreement with the laboratory tests for gypsum deposition under present conditions performed in the deepest part of the mine. These results are also consistent with a multistage precipitation started at different times in the Naica caves (first in caves at the upper level, where gypsum was subsequently dissolved, and only later in the deeper part of the aquifer under stable conditions) and allow us to improve the knowledge on the speleogenetic evolution of these caves.


Minerogenetic mechanisms occurring in the cave environment: an overview, 2011, Onac Bogdan P. , Forti Paolo

Perhaps man’s first motivation to explore caves, beyond using them as shelter, was the search for substances that were not available elsewhere: most of them were minerals. However, for a long time it was believed that the cave environment was not very interesting from the mineralogical point of view. This was due to the fact that most cave deposits are normally composed of a single compound: calcium carbonate. Therefore, the systematic study of cave mineralogy is of only recent origin. However, although only a limited number of natural cavities have been investigated in detail, about 350 cave minerals have already been observed, some of which are new to science. The presence of such unexpected richness is a direct consequence of the variety of rocks traversed by water or other fluids before entering a cave and the sediments therein. Different cave environments allow the development of various minerogenetic mechanisms, the most important of which are double exchange reactions, evaporation, oxidation, hydration-dehydration, sublimation, deposition from aerosols and vapors, and segregation. The cave temperature and pH/Eh strictly control most of them, although some are driven by microorganisms. The cave environment, due to its long-term stability, can sometimes allow for the development of huge euhedral crystals, such as those found in the Naica caves (Mexico), but the presence of extremely small yet complex aggregates of different minerals is far more common. Future development in the field of cave mineralogy will likely be focused mainly on hydrothermal and sulfuric-acid caves and on the role played by micro-organisms in controlling some of the most important minerogenetic processes in caves


Gypsum-carbonate speleothems from Cueva de las Espadas (Naica mine, Mexico): mineralogy and palaeohydrogeological implications, 2012, Gzquez Fernando, Calaforra Jos Maria, Forti Paolo, Rull Fernando, Martnezfras Jess

 

Some of the most outstanding hypogenic gypsum speleothems worldwide have been recently discovered in the Naica mines. The Cueva de las Espadas (Swords Cave), which lies at 120 m depth, hosts a rare type of speleothem called “espada” (“sword”). This study contributes to the understanding of the mineralogical composition of these singular speleothems, by means of their examination using micro-Raman spectroscopy, FT-IR spectroscopy and EDX microprobe. Our data revealed a complex mineralogy comprising a high-purity selenite core covered by several layers of calcite, aragonite and gypsum. Solid inclusions of polymetallic oxides (Mn-Pb-Zn) and graphite were also detected. The position of the water table during the genesis of the “espada” speleothems (over the past 60 kyr) was deduced from their mineralogy. Water level fluctuations at around -120 m depth led to environmental changes within the Cueva de las Espadas. The selenite core and gypsum layers were precipitated under biphasic (water-rock) conditions when the cave was submerged under hydrothermal water. The aragonite precipitation required triphasic (air-water-rock) conditions and occurred when the water table intercepted the cave, allowing the CO2 exchange necessary for carbonate precipitation. Solid inclusions were trapped in an aerobic environment when the gypsum-aragonite boundary condition occurred. A thin calcite layer was precipitated under vadose conditions after the water table definitively moved out of the cave.


Naica caves: perhaps the most important mine caves of the world, 2013, Badino Giovanni, Forti Paolo

In 2005 La Venta Esplorazioni Geografiche together with C/Producciones of Mexico City and Peñoles Society started with the “Projecto Naica” a complex multidisciplinary project to explore, document and study all the relevant aspects of Naica caves. The project lasted about five years. Thanks to the “Projecto Naica” it is now clear that the Naica caves are presently the most important mine caves of the world, not only from the aesthetic point of view but also from the scientific one. But these cave will be likely destroyed in a short span of time and therefore La Venta Esplorazioni Geografiche is now working hard to try to preserve for future generations not only the memory and the records (already achieved with the “Projecto Naica”), but also a significant part of this incredible underground world.


STRONTIUM ISOTOPE RATIOS (87SR/86SR) IN GYPSUM SPELEOTHEMS FROM THE NAICA MINE CAVES (CHIHUAHUA, MEXICO): GENETIC IMPLICATIONS, 2013, Gzquez Fernando, Calaforra Jos Maria, Garcacasco Antonio, Sanna Laura, Forti Paolo

The 87Sr/86Sr ratio of several gypsum speleothems from the caves of the Naica Mine (Chihuahua, Mexico) has been determined in order to evaluate the origin of the saline solution from which they precipitated. The 87Sr/86Sr ratios of the huge selenite crystals from the Cristales Cave (-290 m Level) and of the gypsum core of the “espadas” speleothems from the Espadas Cave (-120 m Level) are 0.707337 and 0.708343, respectively. These values are slightly higher than that of the carbonate host rock (0.7072) as well as that of the Tertiary felsic dikes emplaced in the carbonate sequence (0.7080). They are also lower than those expected for crystallization from seepage water solutions (>0.7090). Therefore, the 87Sr/86Sr values determined for the speleothems at Naica suggest that gypsum in these caves precipitated from a mixture of infiltration water and thermal water. The 87Sr/86Sr ratio of gypsum speleothems is regarded as a useful indicator to infer the rela- tive contribution of meteoric deep thermal water solutions during the genesis of the Naica’s gypsum speleothems.


Determining gypsum growth temperatures using monophase fluid inclusions Application to the giant gypsum crystals of Naica, Mexico: COMMENT, 2013, Garofalo Paolo S. , Forti P. , Gnther D.

Determining gypsum growth temperatures using monophase fluid inclusions Application to the giant gypsum crystals of Naica, Mexico: COMMENT, 2013, Garofalo Paolo S. , Forti P. , Gnther D.

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

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