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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 ponornica is see lost river.?

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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 flowstones (Keyword) returned 17 results for the whole karstbase:
Showing 1 to 15 of 17
Recent flowstone growth rates: field measurements and comparison to theoretical results, 1995, Baker A. , Smart Pl. ,
The model of calcite precipitation kinetics of D. Buhmann and W. Dreybrodt, based on the rate laws of L.N. Plummer et al., is used to predict cave flowstone growth rates. These theoretically modelled growth rates are compared to actual growth rates of recent samples found in cave and mine sites in southwest England. A good agreement is found between modelled and actual growth rates within the 95% confidence level of the determinations, although in general modelled growth rates overestimate actual growth rate by between 2.4 and 4.7 times. Several reasons for this overestimation are discussed, including uncertainties arising from the experimental data of L.N. Plummer et al., seasonal shut-off of water flow onto the flowstones and significant variations in the growth rate determining parameters during the period of flowstone growth. For one flowstone an underestimation of growth rate is observed and is explained by the presence of rimstone pools which pond water on the sample surface

Sannur Cave: A Crescent shaped cave developed in Alabaster formation in Eastern Desert, Egypt, 1995, Gü, Nay G. , Elbedewy F. , Ekmekci M. , Bayari S. , Kurttas T.
An expedition to Egypt set out to explore the Wadi Sannur where no speleological work had taken place. The most notable karst feature identified to date is the Sannur Cave, the largest subterranean chamber known in Egypt. It is situated about 70 km to the southeast of Beni-Suef city in the remote Wadi Sannur of the Eastern Desert where the main rock units belong to Eocene and Pliocene periods. The Eocene is represented by limestone including alabaster which is known to be quarried first by the ancient Egyptians. Sannur Cave is first explored during blasting in the alabaster quarry which caused an artificial entrance to the cave. The cave is a single crescent shape chamber approximately 275 m long and can be arbitrarily divided into two sectionshaving different characteristics; left side gallery and right side gallery. Few speleothems occur in the left side gallery while the right side gallery is decorated intensively with many kinds of spelethem including stalagtites, stalagmites, flowstones, microgours, helictites and soda-straws etc. In addition to surveying the cave, based on the geologic, structural and morphologic observation inside and outside the cave some interpretations on the paleoenvironment an the origin of the cave. Surveying was performed with grade 5D according to BCRA Gradings.

Thesis Abstract: The U-series dating and geochemistry of flowstones from the Great Orme mine, 1996, King H. K.

Comparison of annual luminescent and visible laminae in stalagmites, 1997, Genty D, Baker A, Barnes W,
Polished sections of stalagmites from France and Belgium were examined using UV excitation and natural light in order to examine their annual growth laminae. The most prominent luminescence occurs in the dark compact laminae; this would signify that both types form at the end of Autumn or the beginning of Winter when soil organic matter is flushed into the cave. Under UV excitation, and at a weaker magnification, white porous calcite fabric is found to be much more luminescent than the dark compact one. These results could be due either to optical effects associated with porosity or to the higher luminescence of dark compact laminae

Isolated carbonate platform of Caniego, Spain: A test of the latest Albian worldwide sea-level changes, 1997, Fernandezmendiola Pa, Garciamondejar J,
The upper Albian Caniego carbonate platform consists of a 20-m-thick unit of rudist- and coral-bearing limestones that crops out at the northern margin of the Mena diapir in northern Spain, The limestones were deposited on top of a slowly subsiding area, the Mena paleohigh, a diapiric-induced horst bounded by synsedimentary faults, The Caniego limestones originated in shallow warm tropical waters following a widespread marine transgression at the base of the foraminifera Rotalipora appenninica zone (ammonite Stoliczkaia dispar zone), Around the middle part of the appenninica zone the Caniego limestones underwent subaerial exposure and karst development, Fibrous calcite cements filled the bulk of the fissure-dike and dissolution cavities, Field, petrological, and geochemical data indicate that the fibrous calcites are meteoric flowstones, delta(18)O values in these cements range from -3 parts per thousand to -4.5 parts per thousand and delta(13)C values range from -7 parts per thousand to -14 parts per thousand (relative to the Peedee belemnite [PDB] standard), Thick wedges of nearshore shallow-marine siliciclastic sediments were deposited in paleotrough areas surrounding the Caniego paleohigh while the platform was subaerially exposed, The carbonate platform was drowned in early Cenomanian time and hardground-condensed facies developed during this period (Rotalipora brotzeni zone), Deeper water noncondensed marry sedimentation was reestablished in the mid-Cenomanian (Rotalipora reicheli zone), Comparison of the Iberian Caniego limestones with worldwide successions suggests a coincidence in the timing of platform formation emergence and drowning in several basins of different lithospheric plates, Nevertheless, an overall lack of coordination of sea-level histories from different basins may be related to tectonic movements of the lithospheric plates, Plate rearrangement is invoked as the primary control on relative sea-level changes and sequence development

A mineralogical analysis of karst sediments and its implications to the middle-late Pleistocene climatic changes on the Tibetan Plateau, 1998, Zhang D. D. ,
The minerals in various categories of Tibetan karst sediments were divided into three groups: carbonate, iron and silicate. The carbonate minerals, including calcite, aragonite and dolomite, consist mainly of speleothem, tufa and sinter. Most of the speleothems indicates wetter and warmer periods in early and middle Pleistocene, the youngest being 194,000 years old. The second formation of carbonate mineral, tufa, implies an arid period starting 91,000 years BP. The iron minerals, goethite and hematite, are often mixed up with cave alluvial sediments that are interbedded with flowstones, and the depression sediments. They indicate strong oxidizing environments during their deposition, which is absent at present. The clay minerals, specially kaolinite, were contained in cave alluvial, flowstone and the depression sediments as well. Combined with stratigraphic study and U-series dating, the mineral analysis shows that warmer and wetter climates, which were suitable for speleothem development, probably disappeared 200 ka ago, and drier and colder climates dominated this plateau since then

The Makapansgat Australopithecine site from a speleological perspective, 1999, Latham Alf G. , Herries Andrew, Quinney Patrick, Sinclair Anthony, Kuykendall Kevin,
Remains of Australopithecus africanus from the Limeworks Cave, Makapansgat, South Africa, are believed to belong mainly to a metre-thick, bone-rich, speleothem layer. The flowstone is one stratum among a sequence of speleothems, muds, silts, sands and fine and coarse breccias, the study of which has evoked some disagreement. The limeworkers' excavations revealed some stratigraphic relationships but they have obscured others. Partly because of this, controversy surrounds the supposition about whether there are separated depositional basins within the overall site and, if so, whether strata can be securely correlated. This is important because a reconstruction of an overall stratigraphic sequence was used as a basis for a magnetostratigraphic reversal record and by which the site has been tentatively dated. There is qualification and disagreement about the origin of the various flowstones and the actual depositional environment of the muds and silts. Evidence is presented which rules out some previous interpretations. From the point of view of the Australopithecine fossils themselves, it can be said that the calcite matrix in which they were provenanced was a low-energy environment and that the dense bone accumulation of this layer almost certainly did not arise by the action of floods, as previously supposed. The most likely main cause of the dense accumulation was hyena denning activity. It is clear that further work is needed to see how a reliable overall sequence can be established and that closer sampling is required for magnetostratigraphy

The genesis of the Tennengebirge karst and caves (Salzburg, Austria), 2002, Audra, Ph. , Quinif, Y. , Rochette, P.
Research has been carried out in the Tennengebirge Massif (Salzburg, Austria) with specific attention to karst morphology, cave systems, and sediments. This study reveals the genesis of the karst and the underground systems of the Tennengebirge, since the Oligocene. Large horizontal systems, which date back to the Miocene, were studied through the example of the caves Hornhhle and Eisriesenwelt, which respectively represent Ruinenhhlen (cave ruins) and Riesenhhlen (giant caves). The Cosa-Nostra - Bergerhhle System is typical of a mostly vertical, large, high-relief, alpine cave. The main characteristic of this network is major development in the vadose zone. Shaft morphology is in stairs beneath a faulted roof. At greater depth, they connect to a perched epiphreatic zone, which is typical of a dammed karst. The main underground sediments are of paleoclimatic and hydrodynamic significance, corresponding to hot, stable, or unstable environments (flowstones, reworked weathered rocks) and cold environments (carbonate varves, glacial pebbles). A preliminary study of the Tennengebirge sediments reveals significant information about its evolution throughout Pliocene-Quaternary time. Hhlen- und Karstgenese im Tennengebirge (Salzburg, sterreich) Es handelt sich um Erforschungen des unterirdischen Hhlensystems im Tennengebirge mit Hilfe der Erforschung der Karstsedimente. Durch die Beobachtung der Morphologie und der Ausfllungen kann die Geschichte der verschiedenen Hhlenorganisationen nachgezeichnet werden. Wir haben die groen horizontalen Hhlensysteme des Miozns anhand der Hornhhle und der Eisriesenwelt studiert, die wiederum ein Beispiel fr Ruinen- und Riesenhhlen sind. Das Cosa-Nostra - Bergerhhle System ist ein Beispiel fr die groen vertikalen Alpenschchten, das an seiner ausgeprgten Entwicklung der vadosen Zone erkenntlichist. Die Schchte haben die Morphologie von Treppen unter einem Kluftdach. Sie sind tief unten mit einer gestuften phreatischen Zone verbunden, die einen abgedmmter Karst enthllen. Die wichtigsten unterirdischen Sedimente haben eine Bedeutung auf dem Gebiet der Paloklimatologie und der hydrodynamik. Sie entsprechen entweder warmen und bestndigen oder kalten Umgebungen oder einer Umbegung in der das natrliche Gleichgewicht unterbrochen wurde (Sinterformation, vernderte Sedimente aus Alteriten, Karbonatwarven, glazial Schotter). Die Erforschung der Sedimenten in der Bergerhhle bringt wichtige Informationen ber die Entwicklung der Hhlensysteme im Plio-Quartr. Durch die gesamte Erforschung kann die Entstehung der Hhlen- und Karstgenese im Tennengebirge seit dem Oligozn nachgezeichnet werden.

The genesis of the Tennengebirge karst and caves (Salzburg, Austria), 2003, Audra Ph, Quinif Y. , Rochette P.

Research has been carried out in the Tennengebirge Massif (Salzburg, Austria) with specific attention to karst morphology, cave systems, and sediments. This study reveals the genesis of the karst and the underground systems of the Tennengebirge, since the Oligocene. Large horizontal systems, which date back to the Miocene, were studied through the example of the caves Hornhohle and Eisriesenwelt, which respectively represent Ruinenhohlen (“cave ruins”) and Riesenhohlen (“giant caves”). The Cosa-Nostra - Bergerhohle System is typical of a mostly vertical large high-relief, alpine cave. The main characteristic of this network is major development in the vadose zone. The shafts' morphology is in “stairs beneath a faulted roof.” At greater depth, they connect to a perched epiphreatic zone, which is typical of a dammed karst. The main underground sediments are of paleoclimatic and hydrodynamic significance, corresponding to hot, stable, or unstable environments (flowstones, reworked weathered rocks) and cold environments (carbonate varves, glacial pebbles). A preliminary study of the Tennengebirge sediments reveals significant information about its evolution throughout Pliocene-Quaternary time.


Karst morphology and cave sediments as indicators of the uplift history in the Alpi Apuane (Tuscany, Italy), 2003, Piccini Leonardo, Drysdale Russell, Heijnis Henk,
In the Alpi Apuane (Tuscany, Italy), Late Pliocene to Pleistocene karst landforms are preserved as relict phreatic caves, which were formed in a geomorphic setting very different from that of the present day. The largest karst drainage basin in the region, the Frigido, hosts cave systems with a vertical development totalling 1600 m. Abandoned phreatic cave passages preserved within this and neighbouring basins indicate that former base-levels were situated at up to ~1000 m above the modern valley floors. The passages constitute morphostratigraphic markers that can be used to reconstruct the uplift history of the Apuane. Their vertical distribution suggests two major phases of base-level standstill--one at 1000-1200 m a.s.l. and one at 600-700 m a.s.l. Some of the passages situated at the latter level contain >5 m thick flowstones whose top-beds have an age exceeding the limits of U/Th alpha spectrometric dating (>350 ka). Cave morphology and chronological constraints obtained from speleothems suggest that an important uplift event occurred during the Middle Pleistocene following a period of tectonic standstill of probable latest Early Pleistocene age. Active spring caves close to present-day valley floors contain speleothems whose ages exceed 100 ka, implying that no significant downcutting of the seaward valleys, and consequently no tectonic uplift, has occurred during Late Pleistocene

Black Mn-Fe Crusts as Markers of Abrupt Palaeoenvironmental Changes in El Soplao Cave (Cantabria, Spain), 2011, Gzquez Fernando, Calaforra Jose Maria, Forti Paolo

Peculiar iron and manganese deposits coating walls, floors and ceilings of many galleries are one of the special features of the El Soplao Cave (Cantabria, Spain). These speleothems appear to have been deposited over wall clay deposits, as well as forming part of flowstones. Structure of crusts is essentially amorphous but several manganese and iron oxides were identified like goethite and birnessite, though all occur with a low degree of crystallinity. In the outer layer of the crusts, alteration iron minerals appear that derive from previous minerals in a process probably mediated by microorganisms. EDX microanalyses report fairly high values of Fe and Mn in the crusts, though the Mn/Fe ratio varies considerably as a function of distance from the substrate/bedrock. The present study proposes a genetic model for crust speleothems in El Soplao, based on oscillations of the phreatic level. The origin of these deposits is related to mobilization, under phreatic conditions, of polymetallic sulfides in the host rock. Metal ions (including Fe²⁺ and Mn²⁺) released into the cave under reducing conditions, are oxidized and fixed in a process mediated by bacteria, giving rise to oxides and hydroxides of low crystallinity. The presence of various black intercalated layers in aragonite flowstones indicate periods when cave conditions suddenly changed from vadose, when aragonite is precipitated, to phreatic and epiphreatic conditions, when the Mn-Fe deposits are precipitated. Subsequently, vadose conditions were re-established, leading to the final stages of precipitation of aragonite recorded in the flowstone and recent aragonite helictites on the surface of the Mn-Fe crusts.


Ascending speleogenesis of Sokola Hill: a step towards a speleogenetic model of the Polish Jura, 2011, Gradziń, Ski M. , Hercman H. , Kiciń, Ska D. , Pura D. , Urban J.

The paper deals with the origin of caves in Sokola Hill (Polish Jura). the caves abound in solution cavities in the walls and ceilings, many of them arranged hierarchically, some others arranged in rising sets. blind chimneys and ceiling half-tubes are also present. these features collectively indicate that the caves originated under phreatic conditions by an ascending flow of water, probably of elevated temperature. Phreatic calcite spar, crystallized from water of elevated temperature, lines the cave walls. during the formation of the caves the Jurassic limestone aquifer was confined by impermeable cover. three possible scenarios for the origin of the caves are suggested. the first scenario points to formation of the caves during the Palaeogene prior to the removal of the confining cretaceous marls. the second connects the origin of the caves with regional palaeoflow driven by tectonic loading by carpathian nappes to the south, while the third refers to local topographically driven palaeoflow. both the second and third scenarios assume that the Polish Jura had a cover of Miocene impermeable clastics. All the scenarios account for the origin of the caves in Sokola Hill and explain the common occurrence of ascending caves throughout the Polish Jura.

In the subsequent stages of evolution the caves were partly filled with various deposits. conglomerates composed of Jurassic limestone clasts, quartz sands and sandstones are preserved as erosional remnants, locally covered by or interfingered with calcite flowstones. the clastic deposits were laid down by surface streams that invaded the caves earlier than 1.2 Ma. the caves were not invaded by water from Pleistocene glaciers, which is proved by the assemblage of heavy minerals in the cave clastics.


Structural and host rock controls on the distribution, morphology and mineralogy of speleothems in the Castanar Cave (Spain), 2011, Alonsozarza A. M. , Martinperez A. , Martingarcia R. , Gilpena I. , Melendez A. , Martinezflores E. , Hellstrom J. , Munozbarco P.

The Castanar Cave (central western Spain) formed in mixed carbonate-siliciclastic rocks of Neoproterozoic age. The host rock is finely bedded and shows a complex network of folds and fractures, with a prevalent N150E strike. This structure controlled the development and the maze pattern of the cave, as well as its main water routes. The cave formed more than 350 ka ago as the result of both the dissolution of interbedded carbonates and weathering of siliciclastic beds, which also promoted collapse of the overlying host rock. At present it is a totally vadose hypergenic cave, but its initial development could have been phreatic. The cave's speleothems vary widely in their morphology and mineralogy. In general, massive speleothems (stalactites, stalagmites, flowstones, etc.) are associated with the main fractures of the cave and bedding planes. These discontinuities offer a fairly continuous water supply. Other branching, fibrous, mostly aragonite speleothems, commonly occur in the steeper cave walls and were produced by capillary seepage or drip water. Detailed petrographical and isotope analyses indicate that both aragonite and calcite precipitated as primary minerals in the cave waters. Primary calcite precipitated in waters of low magnesium content, whereas aragonite precipitated from magnesium-rich waters. Differences in isotope values for calcite (-5.2‰ for ?18O and -9.6‰ for ?13C) and aragonite (?18O of -4.5‰ and ?13C of -3.5‰ ) can be explained by the fact that the more unstable mineral (aragonite) tends to incorporate the heavier C isotope to stabilize its structure or that aragonite precipitates in heavier waters. Changes in the water supply and the chemistry and instability of aragonite caused: (1) inversion of aragonite to calcite, which led to the transformation of aragonite needles into coarse calcite mosaics, (2) micritization, which appears as films or crusts of powdery, opaque calcite, and (3) dissolution. Dolomite, huntite, magnesite and sepiolite were identified within moonmilk deposits and crusts. Moonmilk occurs as a soft, white powder deposit on different types of speleothems, but mostly on aragonite formations. Huntite and magnesite formed as primary minerals, whereas dolomite arose via the replacement of both huntite and aragonite. Owing to its variety of speleothems and location in an area of scarce karstic features, the Castanar Cave was declared a Natural Monument in 1997 and is presently the target of a protection and research programme. Although the main products formed in the cave and their processes are relatively well known, further radiometric data are needed to better constrain the timing of these processes. For example, it is difficult to understand why some aragonite speleothems around 350 ka old have not yet given way to calcite, which indicates that the environmental setting of the cave is still not fully understood. 


VALLEY INCISION IN THE NÍZKE TATRY MTS. (SLOVAKIA) ESTIMATED BASED ON PALEOMAGNETIC AND RADIOMETRIC CAVE SEDIMENT DATINGS, 2013, Kadlec J. Bella P. Č, í, ž, Ková, K. Granger D. E. Hercman H. Holú, Bek P. Chadima M. Orvoš, Ová, M. Pruner P. Schnabl P. Š, Lechta S.

 

Up to eleven horizontal cave levels occur at different altitudes in Jánska, Demänovská and Mošnická karst valleys in the Nízke Tatry Mts. Most of the caves are filled with allochthonous sediments transported from the area formed mostly by granite. The cave levels were filled with fluvial sediments in dependence on the valleys incision caused by Neogene and Pleistocene uplift of the mountain range. The fluvial sediments are intercalated with, or capped, by flowstone layers in the caves. The paleomagnetic polarities measured both in clastic and chemogenic sediments indicate the age of deposition. Based on obtained polarity data we are able to distinguish cave sediments deposited during the Brunhes, Matuyama and Gauss chrons. The paleomagnetic interpretation was partly verified by U-series datings of flowstones preserved in the sedimentary sections. Except for the horizontal cave levels located in the karst valleys, additional large cave systems were found at extremely high altitudes in the Nízke Tatry Mts. 600–700 m above the lowest horizontal cave level.


THE SAN PAOLO MINE TUNNEL AT SA DUCHESSA (DOMUSNOVAS, SW SARDINIA): TEN INTERCEPTED NATURAL CAVES AND FIRST DATA ON THE COMPOSITION OF SOME SPELEOTHEMS , 2013, Simone Argiolas, Caddeo Guglielmo Angelo, Casu Lucilla, Muntoni Alberto, Papinuto Silvestro

Since many years cavers from different caving teams are carrying out a systematic study on the caves of Sulcis-Iglesiente, including geomorphological studies. Over thirty natural caves have been explored, surveyed and registered in the past few years, and over half of these have been made accessible by mine galleries. Among these are worth to be mentioned the “Tre Sorelle” of Domusnovas: these are three mine caves intercepted by the San Paolo mine tunnel. This tunnel, whose collapsed entrance has been reopened after a long digging campaign, has been explored and surveyed for around 700 meters. A total of 10 natural caves, mostly developed along fractures, have been explored and mapped, with developments ranging between 10 and 250 meters and depths from 15 to over 160 meters. Only two of these caves were previously known in the Regional Cave Register. In most of the caves, speleothems consist mainly of flowstones, some of which are clear or usually white, others are dark-brown or tending to black. Some samples of the first and the second flowstone types were collected respectively from the “Sesta Sorella” and “Seconda Sorella” Caves. The powders of these samples were analysed by an X-ray diffractometer. The first type consists of thicker layers of white and fibrous aragonite, which sometimes alternate with thinner layers of grey columnar calcite. In some samples, however, calcite interlayers were absent and just aragonite was found. The second type is composed of alternating layers of darkbrown hemimorphite. Some additional analyses were performed on these samples by Laser Ablation ICP-MS to determine the concentration of minor and trace elements in the different layers and mineralogical phases. The most abundant minor elements in calcite layers are Mg and Zn. Magnesium is about constant (~ 2000 ppm) on different spots and remains under the average Mg content of the cave calcite in this region, whereas Zn ranges from 103 to 104 ppm and is well above the Zn average in calcite of caves in the world. Barium concentration is about 80 ppm and more abundant than Pb (20 ppm) and Sr (10 ppm). Barium is also the main minor element in aragonite, where it can reach almost 2000 ppm. The Zn concentration is very high even in aragonite and is comparable to that of Sr (400-500 ppm), overcoming considerably the Pb concentration (20 ppm). In hemimorphite, the most abundant minor elements are Al and Fe (about 104 ppm). However, it was not quantified how much of these are in the hemimorphite lattice or come from some impurities. Actually, we notice that concentration of Fe and Al in the black layers of hemimorphite is an order of magnitude greater than in the brown ones. In addition, the black layers show an abrupt increase of Mn concentration, which overcomes Fe and Al. The evolution of these flowstones is most probably related to the circulation of fluids connected to the oxidation of sulphides, specially sphalerite.


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