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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 chute is an inclined channel or trough in a cave [10].?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
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 notch (Keyword) returned 32 results for the whole karstbase:
Showing 16 to 30 of 32
Eolianites and Karst Development in the Mayan Riviera, Mexico, 2011, Kelley Kristin N. , Mylroie John E. , Mylroie Joan R. , Moore Christopher M. , Collins Laura R. , Ersek Lica, Lascu Ioan, Roth Monica J. , Moore Paul J. , Passion Rex, Shaw Charles

Coastal Quintana Roo, Mexico, including islands such as Cozumel and Isla Mujeres, contains numerous ridges of Quaternary eolian calcarenite in two packages, one Pleistocene and one Holocene. The Pleistocene eolianites are recognizable in the field by well-developed terra rossa paleosol and micritic crust on the surface, containing a fossil epikarst. The foreset beds of these eolianites commonly dip below modern sea level, and fossilized plant root structures are abundant. The Holocene
eolianites lack a well-developed epikarst, and have a calcernite protosol on their surfaces. The degree of cementation, and the grain composition, are not reliable indicators of the age of Quaternary eolianites.

The Pleistocene eolianites have been previously described (e.g. Ward, 1997) as exclusively regressive-phase eolianites, formed by the regression during the oxygen isotope substages (OIS) 5a and 5c. However, certain eolianites, such as those at Playa Copal, contain flank margin caves, dissolution chambers that form by sea water/fresh water mixing in the fresh-water lens. For such mixing dissolution to occur, the eolianite must already be present. As the flank margin caves are found at elevations of 2-6 m above current sea level, the caves must have developed during the last interglacial sea-level highstand, and the eolianites could not have formed on the regression from that or younger highstands. Therefore the eolianites must be transgressive-phase
eolianites developed at the beginning of the last interglacial sea-level highstand, or either transgressive- or regressive-phase eolianites from a previous sea-level highstand that occurred earlier in the Pleistocene. There is no field evidence of oxygen isotope substage 5c or 5a eolianites as suggested by Ward (1997).

Most coastal outcrops show classic regressive–phase Pleistocene eolianites as illustrated by complex and well-developed terra rossa paleosols and epikarst, and dense arrays of fossilized plant roots. However, in addition to flank margin caves, other evidence of transgressive-phase eolianites includes notches in eolianites on the west side of Cozumel, with subtidal marine facies onlapping the notches. The absence of a paleosol between those two units indicates that the eolianite is a transgressive-phase deposit from the last interglacial. All Holocene eolianites are, by definition, transgressive-phase units.


Role of sediment in speleogenesis; sedimentation and paragenesis, 2011, Farrant Andrew R. , Smart Peter L.

Although the effects of sedimentation in caves have been recognised for many years, its role in speleogenesis is frequently overlooked. Influxes of sediment into a cave system fundamentally alter the way cave passages develop, either by alluviation in a vadose environment, forcing lateral corrosion and the development of notches, or by upwards dissolution in a phreatic environment through a process known as paragenesis. Sediment influxes affect the hydrological functioning of a karst aquifer by changing the way conduits behave and subsequently develop both in plan and long section.

Here we give an overview of the mechanisms of cave sedimentation and describe how the process of alluviation and paragenesis affect speleogenesis. A characteristic suite of meso- and micro-scale dissolutional features can be used to recognise paragenetic development, which is reviewed here. In a vadose environment these include alluvial notches, whilst in a phreatic environment, half tubes, anastomoses and pendants, bedrock fins and paragenetic dissolution ramps result. Using these to identify phases of sedimentation and paragenesis is crucial for reconstructing denudation chronologies from cave deposits. We suggest that sedimentation and paragenesis are most likely to occur in certain geomorphological situations, such as ice marginal and periglacial environments, beneath thick residual soils and where rivers can transport fluvial sediment into a cave, either via stream sinks or back-flooding.


El karren litoral a lEs illEs BalEars, 2011, Gmezpujol L. , Forns J. J. , Pomar F.

Coastal exokarstic landforms are quite common features at the Balearic Islands, owing to the presence of extensive coastal limestone outcrops as well as to the suitable hydrodynamic and bioclimatic environment that promotes the development of karst processes. Pinnacles, basin pools, pits and notches, among others, can be seen, especially in the south and southeastern coast of Mallorca, the southern coast of Menorca and all around Formentera. Otherwise the presence of coastal karren in northern Mallorca, Menorca and Eivissa is less prominent due to lithology. Coastal karren at Balearic Islands are quite remarkable because of their morphological variety and occurrence on different rock types, but also as a subject of study on the effect of hydrodynamic gradients and the precipitation and temperature settings or on the biological influence in karst processes. Coastal karren together with plunging cliffs and Quaternary aeolianites exploited as rock quarries are the foremost representative feature of Balearic Islands coastline


Speleogenetic effects of interaction between deeply derived fracture-conduit and intrastratal matrix flow in hypogene karst settings, 2012, Klimchouk A. B. , Tymokhina E. I. , Amelichev G. N.

In carbonate rocks, especially in those with high primary porosity such as most Cenozoic carbonates, the interaction between deeply derived rising flow through sub-vertical fracture-controlled conduits and intrastratal matrix flow of shallower systems can invoke mixing corrosion and result in prominent speleogenetic effects. This paper outlines a conceptual model of such interaction and provides instructive field examples of relevant morphological effects from two different regions within the Prichernomorsky (north Black Sea) basin, where karst features are developed in lower Pliocene, Eocene and Paleocene limestones. In the Crimean fore-mountain region, extensive steep to vertical limestone scarps formed through recent exposure of hypogenic fracture-controlled conduits provide outstanding possibilities to directly examine details of the original karstic porosity. The morphological effects of the conduit/matrix interaction, documented in both caves and exposed scarps, include lateral widening of sub-vertical conduits within the interaction intervals (formation of lateral notches and niches) and the development of side bedding-parallel conduits, pockets and vuggy-spongework zones. Natural convection circulation, invoked by interaction of the two flow systems, spreads the morphological effects throughout the conduit space above the interaction interval. Where the interaction of the two flow systems is particularly strongly localized, such as along junctions of two vertical fracture sets, the resultant morphological effect can take the form of isolated chambers. The variety of speleogenetic features developed through the conduit/matrix interaction, can be broadly grouped into two categories: 1) variously shaped swells of the major fracture conduit itself (morphological features of its walls – niches and pockets), and 2) features of the vuggy-spongework halo surrounding the conduit. This halo includes clustered and stratiform cavities, spongework zones and lateral side conduits. The speleogenetic features due to conduit/matrix flow interaction, especially the halo forms, often demonstrate distinct asymmetry between opposite walls of the conduits. The prominent phenomenon of the vuggy-spongework halo around fracture-controlled conduits has important hydrogeological implications. A comparison of karst features in different regions and rock formations clearly shows that in spite of some distinctions imposed by local structural, sedimentological and paleo-hydrogeological peculiarities, hypogenic speleoforms in limestones of different age and of different degree of diagenetic maturity demonstrate remarkable similarities.


Corrosion morphology and cave wall alteration in an Alpine sulfuric acid cave (Kraushöhle, Austria), 2012, Plan Lukas, Tschegg Cornelius, De Waele Jo Spö, Tl Christoph

Whereasmost karstic cavesworldwide are formed by carbonic acid, a small but significant number of sub-surface cavities are the product of sulfuric acid speleogenesis (SAS). In the Eastern Alps, no cave has so far been attributed to this type. In this multidisciplinary studywe demonstrate that Kraushöhle in northern Styriawas indeed formed by SAS. The cave pattern shows individual chambers, 3D-mazes and blind galleries, as well as typical SAS morphologies such as cupolas, gypsum replacement pockets, corrosion notches and convection niches. “Ceiling pendant drip holes” are described here for the first time and these corrosion features are fully consistent with the SAS model. Other features of Kraushöhle include thick gypsum deposits with strongly depleted δ34S values and other minerals – mostly sulfates – indicating highly acidic conditions. We also studied acid–rock interaction processes giving rise to widespread corrosion and concomitant replacement by gypsum. Petrographic and geochemical analyses reveal the presence of a distinctive alteration layer of highly increased porosity at the interface between the host limestone and the secondary gypsum. Dissolution and replacement of the limestone was fast enough to prevent the development of C and O isotopic alteration halos but resulted in selective leaching of elements. This stable isotope signal is thus different from the pronounced isotope gradient commonly observed in CO2-dominated hypogenic caves. Petrographic observations reveal that the limestone–gypsum replacement was a nearly constant volume process.Whereasmost karstic cavesworldwide are formed by carbonic acid, a small but significant number of sub-surface cavities are the product of sulfuric acid speleogenesis (SAS). In the Eastern Alps, no cave has so far been attributed to this type. In thismultidisciplinary studywe demonstrate that Kraushöhle in northern Styriawas indeed formed by SAS. The cave pattern shows individual chambers, 3D-mazes and blind galleries, as well as typical SAS morphologies such as cupolas, gypsum replacement pockets, corrosion notches and convection niches. “Ceiling pendant drip holes” are described here for the first time and these corrosion features are fully consistent with the SAS model. Other features of Kraushöhle include thick gypsum deposits with strongly depleted δ34S values and other minerals – mostly sulfates – indicating highly acidic conditions. We also studied acid–rock interaction processes giving rise to widespread corrosion and concomitant replacement by gypsum. Petrographic and geochemical analyses reveal the presence of a distinctive alteration layer of highly increased porosity at the interface between the host limestone and the secondary gypsum. Dissolution and replacement of the limestone was fast enough to prevent the development of C and O isotopic alteration halos but resulted in selective leaching of elements. This stable isotope signal is thus different from the pronounced isotope gradient commonly observed in CO2-dominated hypogenic caves. Petrographic observations reveal that the limestone–gypsum replacement was a nearly constant volume process.


Post-speleogenetic biogenic modification of Gomantong Caves, Sabah, Borneo , 2012, Lundberg J, Mcfarlane D. A.

The Gomantong cave system of eastern Sabah, Malaysia, is well-known as an important site for harvesting edible bird-nests and, more recently, as a tourist attraction. Although the biology of the Gomantong system has been repeatedly studied, very little attention has been given to the geomorphology. Here, we report on the impact of geobiological modification in the development of the modern aspect of the cave, an important but little recognized feature of tropical caves. Basic modeling of the metabolic outputs from bats and birds (CO2, H2O, heat) reveals that post-speleogenetic biogenic corrosion can erode bedrock by between ~ 3.0 mm/ka (1 m/~300 ka) and ~ 4.6 mm/ka (1 m/~200 ka). Modeling at high densities of bats yields rates of corrosion of ~ 34 mm/ka (or 1 m/~30 ka). Sub-aerial corrosion creates a previously undescribed speleological feature, the apse-flute, which is semicircular in cross-section and ~ 80 cm wide. It is vertical regardless of rock properties, developing in parallel but apparently completely independently, and often unbroken from roof to floor. They end at a blind hemi-spherical top with no extraneous water source. Half-dome ceiling conch pockets are remnants of previous apse-fluting. Sub-cutaneous corrosion creates the floor-level guano notch formed by organic acid dissolution of bedrock in contact with guano. Speleogenetic assessment suggests that as much as 70–95% of the total volume of the modern cave may have been opened by direct subaerial biogenic dissolution and biogenically-induced collapse, and by sub-cutaneous removal of limestone, over a timescale of 1–2 Ma.


Acqua Fitusa Cave: an example of inactive water-table sulphuric acid cave in Central Sicily, 2012, Vattano M. , Audra Ph. , Bigot J. Y. , Waele J. D. , Madonia G. , Nobcourt J. C.

Hypogenic caves are generated by water recharging from below independently of seepage from the overlying or immediately adjacent surface. These waters are often thermal and enriched in dissolved gases, the most common of which are CO2 and H2S. Hypogenic caves can be thermal caves, sulphuric acid caves, basal injection caves. They differ from epigenic caves in many ways, such as: speleogenetic mechanisms, morphological features, chemical deposits, and lack of alluvial sediments (KLIMCHOUK, 2007; KLIMCHOUK & FORD, 2009; PALMER, 2011). Several studies were conducted to evaluate the hypogenic origin of a large number of caves (AUDRA et alii, 2010; KLIMCHOUK & FORD, 2009; STAFFORD et alii, 2009). A significant contribution was given by the work of Klimchouk (2007) that systematically provided instruments and models to better understand and well define the hypogenic karst processes and landforms. Detailed studies on hypogenic caves were carried out in Italy since the 90s in different karst systems, especially in the Central and Southern Appenines. These studies mainly concerned chemical deposits related to ascending water and micro-biological action (GALDENZI & MENICHETTI, 1995; GALDENZI, 1997; PICCINI, 2000; GALDENZI & MARUOKA, 2003, FORTI & MOCCHIUTTI, 2004; GALDENZI, 2012). In this paper, we present the first results of researches conducted in Acqua Fitusa cave that was believed to be an epigenic cave until today. Acqua Fitusa cave is located in Central Sicily, along the north-eastern scarp of a N-S anticline, westward vergent, forming the Mt. La Montagnola. The cave formed in the Upper Cretaceous Rudist breccias member of the Crisanti Fm., composed of conglomerates and reworked calcarenites with rudist fragments and benthic foraminifers ( CATALANO et alii, 2011). The cave consists at least of three stories of subhorizontal conduits, displaying a total length of 700 m, and a vertical range of 25 m. It represents a clear example of inactive water-table sulphuric acid cave, produced mainly by H 2S degassing in the cave atmosphere. Despite the small size, Acqua Fitusa cave is very interesting for the abundance and variety of forms and deposits related to rising waters and air flow. A ~ 7 m deep inactive thermo-sulphuric discharge slot intersects the floor of some passages for several meters (Fig. 1). Different morphologies of small and large sizes, generated by condensation-corrosion processes, can be observed along the ceiling and walls: ceiling cupolas and large wall convection niches occur in the largest rooms of the cave; deep wall convection niches, in places forming notches, incise cave walls at different heights; condensation-corrosion channels similar to ceiling-half tubes carve the roof of some passages; replacements pockets due to corrosion-substitution processes are widespread; boxwork due to differential condensation-corrosion were observed in the upper parts of the conduits. Sulphuric notches with flat roof, linked to lateral corrosion of the thermal water table, carve the cave walls at different heights recording past stages of base-level lowering. 


SPELEOGENESIS ALONG DEEP REGIONAL FAULTS BY ASCENDING WATERS: CASE STUDIES FROM SLOVAKIA AND CZECH REPUBLIC, 2012, Bella Pavel, Bosak Pavel

The most conspicuous six examples illustrating ascending (perascensum) speleogenesis linked with deep faults/fault systemswere selected from Slovakia and Czech Republic. In the past,the caves have been described as product of phreatic, epiphreaticand vadose speleogenesis related to the evolution of localwater courses and valley incision, and linked mostly with Pleistocenegeomorphic evolution. Our analysis illustrates severalcommon characteristics of caves: (1) they developed along or inclose vicinity of deep faults/fault zones, commonly of regionalimportance; (2) the groundwater ascended due to deep faults/fault systems mostly as results of deep regional circulation ofmeteoric waters from adjacent karst or nonkarst areas; (3) the3D mazes and labyrinths dominate in cave morphology; (4)speleogens (e.g., cupolas, slots, ceiling channels, spongework,rugged phreatic morphology especially along slots) indicateascending speleogenesis in deep phreatic to phreatic environments;(5) they exhibit poor relation to the present landscape;in some of them fluvial sediments are completely missing inspite of surface rivers/streams in the direct vicinity; (6) strongepiphreatic re-modelling is common in general (e.g., subhorizontalpassages arranged in cave levels, water-table flat ceilingsand notches) and related to the evolution of the recent landscape;(7) recharge structures and correlate surface precipitatesare poorly preserved or completely missing (denuded) on thepresent surface in spite of fact that recent recharges broadlyprecipitate travertines; (8) caves can be, and some of them are,substantially older than the recent landscape (Pliocene, Miocene),and (9) caves were formed in conditions of slow water ascent, which differentiate the process from faster vauclusianascending speleogenetical models. Any of described caves containsclear diagnostic features of real hypogene caves. There aremissing evidences that at least heated groundwaters took partduring speleogenesis of studied caves, nevertheless, somewhatincreased water temperature can be expected during speleogenesisat least in some of caves. Any of described caves cannotbe directly characterized as product of thermal waters or hydrothermalprocess (i.e. as real hyperkarst sensu Cigna 1978),therefore they do not represent hypogenic caves.


HYPOGENE SULFURIC ACID SPELEOGENESIS AND RARE SULFATE MINERALS (FIBROFERRITE, JAROSITE SUBGROUP) BAUME GALINIERE CAVE (ALPES-DE-HAUTE-PROVENCE, FRANCE), 2013, Audra P. Gá, Zquez F. Rull F. Bigot J. Y. Camus H.

 

The oxidation of sulfide sources (H2S gas, pyrite, hydrocarbons) produces sulfuric acid that strongly reacts with bedrock, causing limestone dissolution and complex interactions with other minerals. This type of cave development, known as sulfuric acid speleogenesis, is a subcategory of hypogenic speleogenesis, where aggressive water rises from depth. It also produces uncommon minerals, mainly sulfates. Baume Galinière is located in Southern France, in the Vaucluse spring watershed. This small maze cave displays characteristic features such as corrosion notches, calcite dikes and iron crusts, and sulfate minerals. Thirteen minerals were identified, including elemental sulfur, calcite, quartz, pyrite, goethite, gypsum, fibroferrite, plus all of the six members of the jarosite subgroup (jarosite, argentojarosite, ammoniojarosite, hydroniumjarosite, natrojarosite, plumbojarosite). The Baume Galinière deposits are the first documented cave occurrence of argentojarosite and the second known occurrence of plumbojarosite, hydronium jarosite, ammoniojarosite, and fibroferrite. Together with other hypogenic caves in the Vaucluse watershed, Baume Galinière Cave owes its origin in buried conditions to deep water rising along major faults, mixing with meteoric water at the contact of the karst aquifer and overlying impervious cover, and causing pyrite deposition. Sulfuric acid speleogenesis occurred later after base level drop, when the cave arrived in shallow phreatic then in vadose zone, with oxidation of pyrites involving sulfidic gases. Attenuated oxidation is still occurring through condensation of incoming air from outside. Baume Galinière Cave records the position of the paleo-cover and documents its retreat in relationship to valley incision caused by uplift and tilting of the Vaucluse block during Neogene.


PLEISTOCENE SEA LEVEL CHANGES AS REVEALED BY FLANK MARGIN CAVES IN TELOGENETIC LIMESTONES IN SICILY AND SARDINIA (ITALY), 2013, Dangeli I. M. , Waele J. D. , Ruggieri R. , Sanna L.

Coastal karst areas often host many indices of past sea level changes, such as marine terraces, fossiliferous sediments, tidal notches and coastal caves. Tectonic movements can then displace these ancient coastlines vertically. The interplay between rising or falling sea level and uplifting or subsidence can be very complex and difficult to unravel. The combination of a detailed knowledge of marine terraces and the study of some flank margin caves located at various altitudes have allowed to reconstruct the speleogenetic history of the coastal plain of Cornino-Custonaci (NW Sicily). Along the centraleastern coast of Sardinia, instead, the detailed study of the Fico Cave has allowed to recognise it as a flank margin cave developed on five levels, related to Pleistocene sea level highstands. These studies show that this type of mixing corrosion caves is much more widespread than previously thought also in telogenetic limestones. These caves, being excellent sea level markers, might help coastal geomorphologists to understand more on both sea level rise and fall and tectonic movements in coastal areas.


CONDENSATION CORROSION: MEASUREMENTS AND GEOMORPHIC EVIDENCE IN THE FRASASSI CAVES, 2014, Galdenzi S. , Jones D. , Macalady J.

The condensation of acidic waters on subaerial carbonate surfaces (condensation corrosion) can be an important speleogenetic agent under certain conditions (Cigna and Forti, 1986; Sarbu and Lascu, 1997). Specific morphologies associated with condensation corrosion include notches, niches, cupolas, megascallops and domes (Audra, 2009), and have been recognized in many caves from different regions of the world and from different geologic settings. Condensation corrosion can be particularly important in thermal caves, where temperature differences facilitate air convection and water condensation, as well as in sulphidic caves, where degassing and subsequent oxidation of hydrogen sulphide (H2S) gas provides a ready source of acidity to the subaerial cave environment.
In pioneering studies on the formation of sulphidic caves, condensation corrosion via H2S degassing and oxidation to sulphuric acid was considered the primary mechanism for speleogenesis (Principi, 1931; Egemeier, 1981). However, recent research has cast doubt on the importance of subaerial H2S oxidation for sulphidic cave formation (Engel et al., 2004). In the Frasassi cave system, Italy, morphological evidence for both subaerial and subaqueous limestone dissolution has been extensively documented (Galdenzi, 1990; Galdenzi and Maruoka, 2003). In particular, corrosion above the water table has resulted in the formation of massive gypsum deposits as well as specific passage morphologies. Measured rates by Galdenzi et al. (1997) corroborated morphological evidence that condensation corrosion is important at least under certain conditions. Therefore, in order to better define the role of subaerial processes in the Frasassi cave system, we quantified sulphide flux to the cave atmosphere in the modern cave environment, and documented morphological evidence for subaerial corrosion in the past


Inland notches: Implications for subaerial formation of karstic landforms —An example from the carbonate slopes of Mt. Carmel, Israel, 2015,

Inland notches are defined herein as horizontal “C”-shaped indentations, developed on the carbonate slopes or cliffs in the Mediterranean to semi-arid zones. The notches are shaped like half tubes that extend over tens or hundreds of meters along the stream valley slopes. In Mt. Carmel, a series of 127 notches have been mapped. On average, their height and width are 2–2.5mbut they can reach 6min height and 9.5min width. The geomorphic processes that create a notch combine chemical,mechanical, and biogenicweathering,which act together to generate initial dissolution and later flakeweathering (exfoliation) of the bed, forming the notch cavity.We propose an epikarstic-subaerial mechanism for the formation and evolution of the notches. The notches are unique landforms originating fromthe dissolution and disintegration of the rock under subaerial conditions, by differentialweathering of beds with different petrographic properties. The notches follow specific beds that enable their formation and are destroyed by the collapse of the upper bed. The formation and destruction alternate in cyclical episodes and therefore, the notches are local phenomena that vary over time and space


Hypogene Sulfuric Acid Speleogenesis and rare sulfate minerals in Baume Galini`ere Cave (Alpes-de-Haute-Provence, France). Record of uplift, correlative cover retreat and valley dissection, 2015, Audra Philippe, Gґazquez Fernando, Rull Fernando, Bigot Jeanyves, Camus Hubert

The oxidation of hydrocarbons and sulfide sources (H2S, pyrite) produces sulfuric acid that strongly reacts with bedrock, causing limestone dissolution and complex interactions with other minerals from the bedrock or from cave fillings, mainly clays. This type of cave development, known as Sulfuric Acid Speleogenesis (SAS), is a subcategory of hypogene speleogenesis, where aggressive water rises from depth. It also produces uncommon minerals, mainly sulfates, the typical byproducts of SAS. Baume Galinière is located in Southern France, in the Vaucluse spring watershed. This small maze cave displays characteristic SAS features such as corrosion notches, calcite geodes, iron crusts, and various sulfate minerals. Sulfur isotopes of SAS byproducts (jarosite and gypsum) clearly show they derive from pyrite oxidation. Using XRD and micro-Raman spectroscopy, thirteen minerals were identified, including elemental sulfur, calcite, quartz, pyrite, goethite, gypsum, fibroferrite, plus all of the six members of the jarosite subgroup (jarosite, argentojarosite, ammoniojarosite, hydroniumjarosite, natrojarosite, plumbojarosite). The Baume Galinière deposits are the first documented cave occurrence of argentojarosite and the second known occurrence of plumbojarosite, hydronium jarosite, ammoniojarosite, and fibroferrite. In the Vaucluse watershed, there were numerous upwellings of deep water along major faults, located at the contact of the karstic aquifer and the overlying impervious covers. The mixing of deep and meteoric waters at shallow depths caused pyrite depositions in numerous caves, including Baume Galinière. Sulfuric acid speleogenesis occurred later after base-level drop, when the cave was under shallow phreatic conditions then in the vadose zone, with oxidation of pyrites generating sulfuric acid. Attenuated oxidation is still occurring through condensation of moisture from incoming air. Baume Galinière Cave records the position of the semi-impervious paleo-cover and documents its retreat in relationship to valley incision caused by uplift and tilting of the Vaucluse block during the Neogene.


Hypogene Sulfuric Acid Speleogenesis and rare sulfate minerals in Baume Galinière Cave (Alpes-de-Haute-Provence, France). Record .., 2015, Audra P. , Gázquez F. , Rull F. , Bigot J. Y. , Camus H.

The oxidation of hydrocarbons and sulfide sources (H2S, pyrite) produces sulfuric acid that strongly reacts with bedrock, causing limestone dissolution and complex interactions with other minerals from the bedrock or from cave fillings, mainly clays. This type of cave development, known as Sulfuric Acid Speleogenesis (SAS), is a subcategory of hypogene speleogenesis, where aggressive water rises from depth. It also produces uncommon minerals, mainly sulfates, the typical byproducts of SAS. Baume Galinière is located in Southern France, in the Vaucluse spring watershed. This small maze cave displays characteristic SAS features such as corrosion notches, calcite geodes, iron crusts, and various sulfate minerals. Sulfur isotopes of SAS byproducts (jarosite and gypsum) clearly show they derive from pyrite oxidation. Using XRD and micro-Raman spectroscopy, thirteen minerals were identified, including elemental sulfur, calcite, quartz, pyrite, goethite, gypsum, and fibroferrite, plus all of the six members of the jarosite subgroup (jarosite, argentojarosite, ammoniojarosite, hydroniumjarosite, natrojarosite, plumbojarosite). The Baume Galinière deposits are the first documented cave occurrence of argentojarosite and the second known occurrence of plumbojarosite, hydronium jarosite, ammoniojarosite, and fibroferrite. In the Vaucluse watershed, there were numerous upwellings of deep water along major faults, located at the contact of the karstic aquifer and the overlying impervious covers. The mixing of deep and meteoric waters at shallow depths caused pyrite depositions in numerous caves, including Baume Galinière. Sulfuric Acid Speleogenesis occurred later after base-level drop, when the cave was under shallow phreatic conditions then in the vadose zone, with oxidation of pyrites generating sulfuric acid. Attenuated oxidation is still occurring through condensation of moisture from incoming air. Baume Galinière Cave records the position of the semi-impervious paleo-cover and documents its retreat in relationship to valley incision caused by uplift and tilting of the Vaucluse block during the Neogene.


The influence of light attenuation on the biogeomorphology of a marine karst cave: A case study of Puerto Princesa Underground River, Palawan, the Philippines, 2015, Coombes Martin A. , La Marca Emanuela C. , Naylor Larissa A. , Piccini Leonardo, De Waele Jo, Sauro Francesco

Karst caves are unique biogeomorphological systems. Cave walls offer habitat for microorganisms which in-turn have a geomorphological role via their involvement in rock weathering, erosion and mineralisation. The attenuation of light with distance into caves is known to affect ecology, but the implications of this for biogeomorphological processes and forms have seldom been examined. Here we describe a semi-quantitative microscopy study comparing the extent, structure, and thickness of biocover and depth of endolithic penetration for samples of rock from the Puerto Princesa Underground River system in Palawan, the Philippines, which is a natural UNESCO World Heritage Site.

Organic growth at the entrance of the cave was abundant (100% occurrence) and complex, dominated by phototrophic organisms (green microalgae, diatoms, cyanobacteria, mosses and lichens). Thickness of this layer was 0.28 ± 0.18 mm with active endolith penetration into the limestone (mean depth = 0.13 ± 0.03 mm). In contrast, phototrophs were rare 50 m into the cave and biofilm cover was significantly thinner (0.01 ± 0.01 mm, p b 0.000) and spatially patchy (33% occurrence). Endolithic penetration here was also shallower (b0.01mm, p b 0.000) and non-uniform. Biofilm was found 250 m into the cave, but with a complete absence of phototrophs and no evidence of endolithic bioerosion.

We attribute these findings to light-induced stress gradients, showing that the influence of light on phototroph abundance has knock-on consequences for the development of limestone morphological features. In marine caves this includes notches, which were most well-developed at the sheltered cave entrance of our study site, and for which variability in formation rates between locations is currently poorly understood.


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