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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 Schichtfugenkarren is (german.) see bedding grike.?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms

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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 rule (Keyword) returned 45 results for the whole karstbase:
Showing 31 to 45 of 45
Evolution of karst in Messinian gypsum (Monferrato, Northern Italy), 2010, Vigna Bartolomeo, Fioraso Gianfranco, Banzato Cinzia, De Waele Jo

In the Tertiary Basin of Piedmont (Northern Italy) a 100-150 m thick Messinian sedimentary succession crops out, composed of pre-evaporitic clays, gypsum beds and post-evaporitic lacustrine-marine fine-grained sediments. In the Monferrato area the thickness of the evaporite sequence is highly variable (0-140 m) due to an important erosion surface formed at the end of the evaporite cycle and carved in the gypsum beds. Epigenic caves probably formed during this short intra-Messinian phase of emersion. Cave sediments contain benthonic and planctonic foraminiferal associations ranging in age from Burdigalian to Upper Pliocene. These sediments have probably been deposited in recent times, although it cannot be completely ruled out that they accumulated in caves developed in Upper Messinian times. The formation of the most important caves of this area probably started at the end of the Messinian under epigenic conditions. Possibly, those inherited caves enlarged slowly during the Quaternary in an intrastratal and confined hypogene karst system. 


Geomorphologische Untersuchung und genetische Interpretation der Dachstein- Mammuthhle (sterreich), 2010, Plan L. , Xaver A.
The speleogenesis of Dachstein-Mammuthhle, the third-longest cave system in the Northern Calcareous Alps, has been discussed controversially in the past. Using morphologic mapping and morphometric data of the central parts of the cave in combination with modern speleogenetic models a re-evaluation of its development is attempted. The geometry of the cave and several small-scale features (e.g., scallops, karren, ceiling meanders), which date back to the early history of the cave formation, lead to the following interpretion: old phreatic parts (galleries, mazes, and some pits) developed under epiphreatic conditions during flood events, followed by younger, vadose canyon-shaft-systems. Scallops and sedimentary structures indicate a general westward flow direction. Sediments played an important role during the formation of the profiles, i.e. the profiles expanded upward (paragenesis) because the floor of the galleries was sealed by sediments, and only part of the cross section, as it can be seen today after removal of these sediments, was occupied by water. This is relevant for calculations of the palaeodischarge from mean scallop lengths and cross-section areas. Paragenesis can only be ruled out for the origin of the keyhole profile of the so-called Canyon (near the Westeingang) and the palaeodischarge was estimated to 16 m/s. This, however, was probably only a fraction of the total discharge of this system as several additional large galleries occur at the same cave level. The former catchment area was probably located south of todays Northern Calcareous Alps

On the formation of collapse dolines: A modelling perspective, 2011, Gabrovš, Ek Franci, Stepiš, Nik Uroš,

Collapse dolines are among the most striking surface features in karst areas. Although they can be the result of different formation mechanisms, evidence suggests that large collapse dolines form due to chemical and mechanical removal of material at and below the level of groundwater. We have applied a genetic model of a two-dimensional fracture network to calculate the rate of dissolutional bedrock removal in the heavily fractured (crushed) zone intersecting a karst conduit in the phreatic zone. To account for infilling and breakdown processes in the crushed zone two simple rules were added to the basic model: 1) continuous infilling of dissolutionally created voids prevents fractures from growing beyond some limited aperture, although the dissolution proceeds, 2) discontinuous collapsing causes sudden closure of a fracture once some critical aperture has been reached. Both rules limit the transmissivity of the network and the related flow rates. Therefore, the constant head difference between the input and the output points is sustained and the flow remains distributed over the entire crushed zone. Provided that restrictions posed by the two rules permit turbulent flow, dissolution rates also remain high in the entire region. High surface area of water–rock contact and high dissolution rates result in high overall removal rates of rock from the crushed zone, one of the necessary conditions for the formation of large closed depressions. Despite the fact that the model neglects some processes and dynamics that would increase the removal rate, the results suggest that large closed depressions could form in the order of 1 million years.


Integrating geomorphological mapping, trenching, InSAR and GPR for the identification and characterization of sinkholes: A review and application in the mantled evaporite karst of the Ebro Valley (NE Spain), 2011, Gutié, Rrez Francisco, Galve Jorge Pedro, Lucha Pedro, Castañ, Eda Carmen, Bonachea Jaime, Guerrero Jesú, S

This contribution illustrates the advantages of integrating conventional geomorphological methods with InSAR, ground penetrating radar and trenching for sinkhole mapping and characterization in a mantled evaporite karst area, where a significant proportion of the karstic depressions have been obliterated by artificial fills. The main practical aim of the investigation was to elucidate whether buried sinkholes overlap the areas planned for the construction of buildings and services, in order to apply a preventive planning strategy. Old aerial photographs and detailed topographic maps were the most useful sources of information for the identification of sinkholes and helped to obtain information on their chronology, either a minimum age or bracketing dates. The InSAR technique provided subsidence rate values ranging from 4.4 to 17.3 mm/yr consistent with the spatial distribution of the mapped sinkholes. This quantitative deformation data helped corroborating independently the existence of active buried sinkholes and improving the delineation of their limits. The GPR profiles contributed to the precise location of sinkhole edges, provided information on the geometry of buried sinkholes and deformation structures and helped to site trenches and to rule out the existence of sinkholes in particular areas. The main input derived from the trenches includes: (1) Confirming or ruling out anomalies of the GPR profiles attributable to subsidence. (2) Precise location of the edge of some filled sinkholes. (3) Information on subsidence mechanisms recorded by various deformation structures and cumulative subsidence magnitude. (4) Calculating minimum long-term subsidence rates using radiocarbon dates obtained from deformed sinkhole deposits. (5) Unequivocal evidence of active subsidence in areas assigned for the construction of buildings


Mechanisms of heat exchange between water and rock in karst conduits, 2011, Covington M. D. , Luhmann A. J. , Gabrovsek F. , Saar M. O. , Wicks C. M.

Previous studies, motivated by understanding water quality, have explored the mechanisms for heat transport and heat exchange in surface streams. In karst aquifers, temperature signals play an additional important role since they carry information about internal aquifer structures. Models for heat transport in karst conduits have previously been developed; however, these models make different, sometimes contradictory, assumptions. Additionally, previous models of heat transport in karst conduits have not been validated using field data from conduits with known geometries. Here we use analytical solutions of heat transfer to examine the relative importance of heat exchange mechanisms and the validity of the assumptions made by previous models. The relative importance of convection, conduction, and radiation is a function of time. Using a characteristic timescale, we show that models neglecting rock conduction produce spurious results in realistic cases. In contrast to the behavior of surface streams, where conduction is often negligible, conduction through the rock surrounding a conduit determines heat flux at timescales of weeks and longer. In open channel conduits, radiative heat flux can be significant. In contrast, convective heat exchange through the conduit air is often negligible. Using the rules derived from our analytical analysis, we develop a numerical model for heat transport in a karst conduit. Our model compares favorably to thermal responses observed in two different karst settings: a cave stream fed via autogenic recharge during a snowmelt event, and an allogenically recharged cave stream that experiences continuous temperature fluctuations on many timescales.


Dams and Reservoirs in Karst , 2011, Milanovic, Petar

Construction of dams and reservoirs in karst is historically known as a very risky task. Inspite of very detailed geophysical investigations and repeated sealing treatments, the possibility for dam failure cannot be eliminated. In the karst environment, with its highly random distribution of dissolution features, some uncertainties always remain. The final determination of the adequacy of sealing measures comes after the first reservoir impoundment or even later. In many worldwide examples, watertightness treatment during dam construction was only partially successful, with some remedial work after impoundment being quite common. However, in some cases, the problem is simply too complicated and cannot be overcome. Special approaches have to be undertaken in order to prevent seepage from reservoirs. The key elements are a good geological map and proper geophysical investigations. These investigations are key prerequisites of dam construction in karst and cutting costs through restricting them usually results in increasing the chance of project failure. To deal with karst successfully, innovation, engineering practice, execution feasibility, and commercial understanding have to be undertaken. Grouting alone is definitely not adequate in the case of large karst conduits. Special treatment of large caverns and flexibility during grout curtain execution, including modifications and adaptations on the basis of the geological findings, should be the standard procedure for dam construction in karst to minimize risk. Such an approach is the basic worldwide rule in the fight against leakage from dam sites and reservoir abutments.


Höhlen der Schwäbischen Alb als Pegelschreiber für Flussgeschichte und Tektonik in Südwestdeutschland seit dem Miozän, 2011, Strasser Marcel

In south western Germany the karstified plateau of the Swabian Alb consisting of Upper Jurassic limestones hosts numerous caves, dolines, and dry valleys. Known strath terraces, conglomerates, volcanoes, and impact craters within the study area already provided important time stamps for former studies reconstructing landscape history. It is widely understood, that spatial distribution of most karst features is closely related to the palaeo-water-table and its discontinuous lowering over time, which in turn is the result of incision and/or uplift. The situation of the Swabian Alb at the northern rim of the Northern Alpine Foreland Basin and east of the Rhine Graben valley is the reason for this uplift. Many caves can be used as gauge for vertical displacement, considering horizontal cave passages as product of a stationary palaeowater-table and vertical sections as result of falling base level. In contrast recent studies deal with a different type of speleogenesis independent of base level. This hypogenic speleogenesis must be discussed for the caves of the Swabian Alb. The recently discovered cave named Laierhöhle near Geislingen/Steige is a typical 3d-maze providing several horizontal levels. Passage pattern and distinctive corrosion features match with morphologies (feeders, rising wall- and ceiling channels, outlets) characteristical for hypogenic speleogenesis. However, artesian situations, hydrothermal water or confined aquifers as critical conditions for hypogenic speleogenesis can not be verified. Other features like horizontal passages, water table markers, key-hole-features, and massive stratified sediment bodies are pointing to an epigenic, water-table related speleogenesis. In this study therefore a mixed model for speleogenesis of Laierhöhle is presented, assuming a strong initial deep-phreatic corrosion along fractures and fissures, followed by intensive widening at the palaeo water-table resulting in the formation of horizontal passages. Correlations between horizontal cave-levels, valley-bottoms, strath-terraces, local conglomerates and other caves lead to new and more precise data on the fluvial history, changing drainage pattern, and the uplift of parts of southwest Germany.

In the course of Examinations of cave sediments spherical metallic particles were detected. These magnetic spherules are ablation-products from meteorites during impact. After fallout and flushing into karstic voids and caves the spherules got archived till today. Spherules within Laierhöhle, Laichinger Tiefenhöhle and Mordloch are supposed to originate from the impact event producing the impact craters Steinheimer Becken and/or the Nördlinger Ries 14.59 Ma ago. Within most of the cave sediments spherules are accompanied by crystals of titano-magnetite, which built during volcanic activity of the Urach-Kirchheim volcanic field. Both spherules and titano-magnetites are proxies for re-deposited Mid Miocene Sediments. In this study I could correlate speleogenetic with dated geomorphic features and thus came to a chronology of events. The Laierhöhle records five episodes of long-term stability of the karst water table covering the time-span from late Middle Miocene until the Pliocene/Pleistocene transition. The first two stable episodes can be dated to the late Middle Miocene and Late Miocene (horizontal levels 1 and 2a). An episode responsible for the formation of level 2b falls within Early Pliocene time. Levels 3a and 3b are spatially well separated but must have formed within a relatively short timespan towards the end of the Pliocene. In the working area, total depth of penetrative karstification was in the order of 120 m. This penetration has been accomplished over a period of approximately 12 Ma resulting in an average uplift rate of 0.01 mm/a.


Marine seismic-reflection data from the southeastern Florida Platform: a case for hypogenic karst, 2013, Cunningham, Kevin J.

Recent acquisition of twenty marine seismic-reflection profiles suggests a hypogenic karst origin for the Key Biscayne sinkhole located on the seafloor of Miami Terrace at the southeastern part of Florida Platform. Analysis of the seismic-reflection data strongly suggest the submarine sinkhole was produced by dissolution and collapse of Plio(?)-Pleistocene age carbonate strata. A complex fault system that includes compres-sional reverse faults underlies the sinkhole, providing a physical system for the possible exchange of groundwater with the sinkhole. One seismic profile is suggestive of a mas-ter feeder pipe beneath the sinkhole. The feeder pipe is characterized by seismic-reflection configurations that resemble megabreccia and stratal collapse. The sinkhole is located at a depth of about 365 m below sea level. The record of sea-level change dur-ing the Plio(?)-Pleistocene and amount of subsidence of the Florida Platform during this span of time indicates that the sinkhole has always been submerged at a water depth of about 235 m or more. Thus, the near-surface epigenic karst paradigm can be ruled out. Possible hypogenic models for sinkhole formation include ascending fluids along the fault system, such as, dissolution related to the freshwater/saltwater mixing at a regional groundwater discharge site, or processes related to gases derived from gener-ation of hydrocarbons within deep Mesozoic strata. Hydrocarbon-related karstification provides several possible scenarios: (1) oxidation of deep oil-field derived hydrogen sulfide at or near the seafloor to form sulfuric acid, (2) reduction of Cretaceous or Paleocene anhydrite or both by oil-field methane to form hydrogen sulfide and later oxidation to form sulfuric acid, and (3) carbon-dioxide charged groundwater reacting to form carbonic acid. Further, anerobic microbes could form methane outside of a hy-drocarbon reservoir that ascends through anhydrite to form hydrogen sulfide and later oxidized to sulfuric acid.


INVESTIGATIONS INTO THE POTENTIAL FOR HYPOGENE SPELEOGENESIS IN THE CUMBERLAND PLATEAU OF SOUTHEAST KENTUCKY, U.S.A., 2013, Florea Lee J.

 

This manuscript offers preliminary geochemical evidence that investigates the potential for hypogene speleogenesis in the Cumberland Plateau of southeastern Kentucky, U.S.A. The region was traditionally considered a classic example of epigenic karst, but new insights have uncovered tantalizing observations that suggest alternatives to simple carbonic acid speleogenesis. Such first-order observations have included natural petroleum seeps at the surface and in caves, occasional cave morphologies consistent with action of hypogene fluids, and prolific gypsum within cave passages. To this point, geochemical data from caves and springs verify carbonic acid as the primary dissolutional agent; however, these same analyses cannot rule out sulfuric acid as a secondary source of dissolution. In this paper, Principal Component Analysis of ionic data reveals two components that coordinate with parameters associated with “karst water” and shallow brine. In contrast, molar ratios of Ca+ and Mg+ as compared to HCO3 - and SO4 2- closely follow the reaction pathway stipulated by the carbonate equilibria reactions. Despite these data, the role, if any, of hypogene speleogenesis in the karst of the Cumberland Plateau remains inconclusive. It is very likely that carbonic acid dominates speleogenesis; however, contributions from sulfuric acid may influence our understanding of “inception” and carbon flux within these aquifers.


‘Looping caves’ versus ‘water table caves’: The role of base-level changes and recharge variations in cave development, 2014, Gabrovšek Franci, Häuselmann Philipp, Audra Philippe

The vertical organisation of karst conduit networks has been the focus of speleogenetic studies for more than a century. The four state model of Ford and Ewers (1978), which still is considered as the most general, relates the geometry of caves to the frequency of permeable fissures. The model suggests that the ‘water table caves’ are common in areas with high fissure frequency, which is often the case in natural settings. However, in Alpine karst systems, water table caves aremore the exception than the rule. Alpine speleogenesis is influenced by high uplift, valley incision rates and irregular recharge. To study the potential role of these processes for speleogenesis in the dimensions of length and depth, we apply a simple mathematical model based on coupling of flow, dissolution and transport.We assume a master conduit draining thewater to the spring at a base level. Incision of the valley triggers evolution of deeper flow pathways,which are initially in a proto-conduit state. Themaster conduit evolves into a canyon following the valley incision,while the deep pathways evolve towards maturity and tend to capture the water fromthe master conduits. Two outcomes are possible: a) deep pathways evolve fast enough to capture all the recharge, leaving the master conduit dry; or b) the canyon reaches the level of deep pathways before these evolve to maturity. We introduce the Loop-to-Canyon Ratio (LCR), which predicts which of the two outcomes is more likely to occur in certain settings. Our model is extended to account for transient flow conditions. In the case of an undulating master conduit, floodwater is stored in troughs after the flood retreat. This water seeps through sub-vertical fractures (‘soutirages’) connecting the master conduitwith the deep pathways. Therefore, the loops evolve also during the dry season, and the LCR is considerably increased. Although themodel is based on several approximations, it leads to some important conclusions for vertical organisation of karst conduit networks and stresses the importance of base-level changes and transient recharge conditions. It therefore gives an explanation of speleogenesis that relies much more on the dynamic nature of water flow than on the static fracture density


Fingerprinting water-rock interaction in hypogene speleogenesis: potential and limitations of isotopic depth-profiling, 2014, Spötl Ch, Dublyansky Y.

Dissolution processes in karst regions commonly involve (meteoric) water whose stable isotopic (O, H, C) composition is distinctly different from that of the paleowaters from which the host rock (limestone, dolostone) formed. This, in theory, should lead to isotopic alteration of the host rock beyond the active solution surface as the modern karst water is out of isotopic equilibrium with the carbonate rock. No such alteration has been reported, however, in epigenetic karst systems. In contrast, isotopic alteration, commonly referred to as isotopic halos or fronts, are known from various hypogene systems (ore deposits, active hydro­thermal systems, etc.). These empirical observations suggest that stable isotope data may be a diagnostic tool to identify hypogene water-rock interactions particularly in cave systems whose origin is ambiguous.

We have been testing the applicability of this assumption to karst settings by studying the isotopic composition of carbonate host rocks in a variety of caves showing clear-cut hypogene morphologies. Cores drilled into the walls of cave chambers and galleries were stud­ied petrographically and the C and O isotope composition was analyzed along these cores, which typically reached a depth of 0.5 to 1.2 m. We identified three scenarios: (a) no isotopic alteration, (b) a sigmoidal isotope front within a few centimeters of the cave wall, and (c) pervasive isotope alteration throughout the entire core length. Type (a) was found in caves where the rate of cave wall retreat apparently outpaced the rate of isotopic alteration of the wall rock (which is typical, for example, for sulfuric acid speleogenesis). Type (c) was observed in geologically young, porous limestone showing evidence of alteration zones up to 5 m wide. The intermediate type (b) was identified in hypogene karst cavities developed in tight limestone, dolostone and marble.

Our data in conjunction with evidence from speleothems and their geochemical and fluid-inclusion composition suggest that the spa­tial extent of the isotopic alteration front depends on the porosity and permeability, as well as on the saturation state of the water. Wider alteration zones primarily reflect a higher permeability. Shifts are most distinct for oxygen isotopes and less so for carbon, whereby the amplitude depends on a number of variables, including the isotopic composition of unaltered host rock, the isotopic composition of the paleofluid, the temperature, the water/rock ratio, the surface of water-rock contact, the permeability of the rock, and the time available for isotope exchange. If the other parameters can be reasonably constrained, then semi-quantitative temperature estimates of the paleowater can be obtained assuming isotopic equilibrium conditions.

If preserved (scenarios b and c), alteration fronts are a strong evidence of hypogene speleogenesis, and, in conjunction with hypogene precipitates, allow to fingerprint the isotopic and physical parameters of the altering paleofluid. The reverse conclusion is not valid, however; i.e. the lack of evidence of isotopic alteration of the cave wall rock cannot be used to rule out hypogene paleo-water-rock interaction.


HYPOGENE SPELEOGENESIS AND CO2: SUGGESTIONS FROM KARST OF ITALY, 2014, Menichetti, M.

The carbon dioxide produced in the soil and dissolved in the percolation water is considered as the main agent for karstification in the carbonate rocks. Superficial morphologies and underground caves are product of the corrosion of the limestone, while carbonate speleothems is the other end member of the process.
Hypogene speleogenesis driven by deep seated fluids is the cave formation processes for the main karst systems in the Apennines of Italy. Hydrogen sulfide and endogenic carbon dioxide are the main agents for underground karst corrosion and the soil carbon dioxide plays a secondary rule. The limestone corrosion driven by hydrogen sulfide produces gypsum deposits in caves that could be assumed as the indicator of the hypogene speleogenesis. The action of endogenic carbon dioxide in the cave formation, especially if it operates at lower temperature, is not easy to detect and the resulting cave morphology is not helpful to recognize the cave formation process.
The main sources of carbon dioxide in the underground karst system in the Apennines of Italy can be related to different processes driven by the endogenic fluids emissions. The crustal regional degassing seems to be the prevalent source for carbon dioxide in the karst massifs with the main release in the groundwater. Hydrogen sulfide and methane oxidation, possibly mediated by bacteria activity, are other sources in the buried Cenozoic sediments. Releasing of carbon dioxide along the faults and in the fractures occurring in the carbonate rocks is an important source, especially in the seismically active area. Finally, thermogenic reactions with carbonate rocks are well known as one of the main production mechanism of carbon dioxide released in the atmosphere.
Data from carbon dioxide monitoring in several caves show a relevant contribution of the endogenic carbon dioxide (about 75 %) in the karst system which drives the speleogenesis reactions and shapes the underground morphologies.


Geologic constraints and speleogenesis of Cova des Pas de Vallgornera, a complex coastal cave from Mallorca Island (Western Mediterranean), 2014, Ginés J. , Fornós J. J. , Ginés A. , Merino A. , Gràcia F.

The flat areas of eastern and southern Mallorca host a remarkable coastal karst, where Cova des Pas de Vallgornera stands out due to its length (more than 74 km) and its special morphological suite. The pattern of the cave is quite heterogeneous showing sharp differences produced by the architecture of the Upper Miocene reef: spongework mazes and collapse chambers dominate in the reef front facies, whereas joint-guided conduits are the rule in the back reef carbonates. Regarding the speleogenesis of the system, a complex situation is envisaged involving three main agents: coastal mixing dissolution, drainage of meteoric diffuse recharge, and hypogene basal recharge related to local geothermal phenomena. The cave system is disposed in two main tiers of passages, of which geomorphologic interpretations are derived from their elevation data. The evolutionary trends as well as the chronology of the different cave sections are difficult to establish owing to the frequent shifting of the coastal base level during the Plio-Quaternary. In this respect, the genesis and evolution of the cave were fully controlled by sea-level fluctuations in the Western Mediterranean basin, with the main phases of cave formation, based on vertebrate paleontological data, going back to mid-Pliocene times.


Earliest evidence of pollution by heavy metals in archaeological sites, 2015, Guadalupe Monge, Francisco J. Jimenezespejo, Antonio Garcíaalix, Francisca Martínezruiz, Nadine Mattielli, Clive Finlayson, Naohiko Ohkouchi, Miguel Cortés Sánchez, Jose María Bermúdez De Castro, Ruth Blasco, Jordi Rosell, José Carrión, Joaquí

Homo species were exposed to a new biogeochemical environment when they began to occupy caves. Here we report the first evidence of palaeopollution through geochemical analyses of heavy metals in four renowned archaeological caves of the Iberian Peninsula spanning the last million years of human evolution. Heavy metal contents reached high values due to natural (guano deposition) and anthropogenic factors (e.g. combustion) in restricted cave environments. The earliest anthropogenic pollution evidence is related to Neanderthal hearths from Gorham's Cave (Gibraltar), being one of the first milestones in the so-called “Anthropocene”. According to its heavy metal concentration, these sediments meet the present-day standards of “contaminated soil”. Together with the former, the Gibraltar Vanguard Cave, shows Zn and Cu pollution ubiquitous across highly anthropic levels pointing to these elements as potential proxies for human activities. Pb concentrations in Magdalenian and Bronze age levels at El Pirulejo site can be similarly interpreted. Despite these high pollution levels, the contaminated soils might not have posed a major threat to Homo populations. Altogether, the data presented here indicate a long-term exposure of Homo to these elements, via fires, fumes and their ashes, which could have played certain role in environmental-pollution tolerance, a hitherto neglected influence.


Hypogene speleogenesis in dolomite host rock by CO2-rich fluids, Kozak Cave (southern Austria), 2015,

A growing number of studies suggest that cave formation by deep-seated groundwater  (hypogene) is a more common process of subsurface water-rock interaction than previously  thought. Fossil hypogene caves are identified by a characteristic suite of morphological  features on different spatial scales. In addition, mineral deposits (speleothems) may provide  clues about the chemical composition of the paleowater, which range from CO2-rich to  sulfuric acid-bearing waters. This is one of the first studies to examine hypogene cave  formation in dolomite. Kozak Cave is a fossil cave near the Periadriatic Lineament, an area  known for its abundance of CO2-rich springs. The cave displays a number of macro-, mesoand  micromorphological elements found also in other hypogene caves hosted in limestone,  marble or gypsum, including cupolas, cusps, Laughöhle-type chambers and notches. The  existance of cupolas and cusps suggests a thermal gradient capable of sustaining free  convection during a first phase of speleogenesis, while triangular cross sections (Laughöhle  morphology) indicate subsequent density-driven convection close to the paleowater table Notches mark the final emergence of the cave due to continued rock uplift and valley  incision. Very narrow shafts near the end of the cave may be part of the initial feeder system,  but an epigene (vadose) overprint cannot be ruled out. Vadose speleothems indicate that the  phreatic phase ended at least about half a million years ago. Drill cores show no evidence of  carbon or oxygen isotope alteration of the wall rock. This is in contrast to similar studies in  limestone caves, and highlights the need for further wall-rock studies of caves hosted in  limestone and dolomite


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