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Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

Did you know?

That tube, lava is see lava cave.?

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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 preservation (Keyword) returned 81 results for the whole karstbase:
Showing 1 to 15 of 81
Some Simple Techniques and Apparatus for the Collection and Preservation of Animals from Cave Habitats, 1963, Driver D. B.

Sea Caves of King Island, 1979, Goede Albert, Harmon Russell, Kiernan Kevin

Investigation of two King Island sea caves developed in quartzitic rocks shows them to contain a wealth of clastic and chemical sediments. Clastic sediments consist of wave-rounded cobbles, debris cones, and angular rock fragments produced by frost weathering and crystal wedging. Chemical deposits include a variety of calcium carbonate speleothems and also gypsum occurring as wall crusts and blisters. The latter appear to be a speleothem type of rare occurrence. Growth of gypsum is responsible for some crystal wedging of the bedrock. Three basal stalagmite samples have been dated by the Th/U method indicating Late Pleistocene as well as Holocene speleothem growth. The caves are believed to have formed by preferential wave erosion during the Last Interglacial in altered and fractured quartzites. The evidence for pre-Holocene evolution of sea caves and geos in the Tasman region is summarised. Tasmania and the Bass Strait Islands provide a particularly favourable environment for the preservation of relict landforms on rocky coasts because of Late Quaternary uplift. The potential of further studies of sea caves to test two recently advanced archaeological hypotheses is discussed.


Relation dbit / niveau de la mer de l'mergence littorale d'Almyros Agios Nikolaos (Crte, Grce), 1983, Bezes C. , Joseph C.
RELATION FLOW-SEA LEVEL OF SALT KARSTIC RESURGENCE BY MULTIPLE REGRESSION WITH THE WATER TABLE - The Amlyros Agios Nikolaos spring is a brackish karstic resurgence on the eastern coast of Crete. Its flow varies in the reverse order versus the sea level. The circulation of the out effect recession curve of the spring was done with the building of a multiple regression between the sea level, the spring flow and the water table. An adjustment about the mean sea level ensures the preservation of outflow.

Paleokarst - a Systematic and Regional Review, 1989,

Description
Prepared by some of the world's leading experts in the field, this book is the first summarizing work on the origin, importance and exploitation of paleokarst. It offers an extensive regional survey, mainly concerning the Northern Hemisphere, as well as a thorough analysis of the problems of research into paleokarst phenomena, with particular emphasis on theoretical contributions and practical exploitation. By concentrating on phenomena which have appeared in the course of geological history, the book represents a substantial development in the general theory of paleokarst and demonstrates the advantages of a comprehensive approach to the problem. Considerable emphasis is put on the economic importance of paleokarst phenomena, from the point of view of exploiting significant deposits of mineral raw materials, as well as from a civil engineering and hydrological point of view. Since the publication deals with a boundary scientific discipline, it is intended for specialists from various branches of science: geologists, paleontologists, economic geologists, geographers, mining engineers and hydrogeologists.

Contents
List of Contributors. Foreword.

Part I. Introduction.
Introduction (P. Bosák et al.). Paleokarst as a problem (J. Głazek, P. Bosák, D.C. Ford). Terminology (P. Bosák, D.C. Ford, J. Głazek).

Part II. Regional Review.
Paleokarst of Belgium (Y. Quinif). Paleokarst of Britain (T.D. Ford). Paleokarst of Norway (S.-E. Lauritzen). Paleokarst of Poland (J. Głazek). Paleokarst of Czechoslovakia (P. Bosák, I. Horáček, V. Panoš). Paleokarst of Hungary (G. Bárdossy, L. Kordos). Hydrothermal paleokarst of Hungary (P. Müller). Paleokarst of Italy. Selected examples from Cambrian to Miocene (M. Boni, B. D'Argenio). Paleokarst-related ore deposits of the Maghreb, North Africa (Y. Fuchs, B. Touahri). Paleokarst of Yugoslavia (D. Gavrilović). Paleokarst of Bulgaria (I. Stanev, S. Trashliev). Paleokarst of Romania (M. Bleahu). Paleokarst of the Union of Soviet Socialist Republics (R.A. Tsykin). Paleokarst of China (Zhang Shouyue). Paleokarst of Canada (D.C. Ford). Paleokarst of the United States (M.V. Palmer, A.N. Palmer).

Part III. Mineral Deposits Connected With Karst.
An introduction to karst-related mineral deposits (P. Bosák). Pb-Zn ores (S. Dżułyński, M. Sass-Gustkiewicz). Bauxites (G. Bárdossy). Iron ore deposits in paleokarst (G. Bárdossy, Y. Fuchs, J. Głazek). Clays and sands in paleokarst (P. Bosák). The oceanic karst: modern bauxite and phosphate ore deposits on the high carbonate islands (so-called ``Uplifted Atolls'') of the Pacific Ocean (F.G. Bourrouilh-le Jan). Paleokarst-related uranium deposits (Y. Fuchs).

Part IV. Hydrogeology and Engineering Hazards in Paleokarst Areas.
Paleokarst as an important hydrogeological factor (J. Zötl). Hydrogeological problems of opencast and underground mining of mineral deposits encountered during their exploration, development and exploitation stages (P. Bosák). Hydrogeological problems of the Cracow-Silesia Zn-Pb ore deposits (Z. Wilk). Hydrogeological problems of Hungarian bauxite and coal deposits (T. Böcker, B. Vizy). Paleokarst in civil engineering (A. Eraso). Interaction between engineering and environment in the presence of paleokarst: some case histories (J. Głazek).

Part V. Paleokarst as a Scientific Subject.
Special characteristics of paleokarst studies (I. Horáček, P. Bosák). Tectonic conditions for karst origin and preservation (J. Głazek). Problems of the origin and fossilization of karst forms (P. Bosák). Biostratigraphic investigations in paleokarst (I. Horáček, L. Kordos).

Part VI. Conclusions. Part VII. References. Part VIII. Indexes.
Author Index. Geographical Index. Subject Index.

Bibliographic & ordering Information
Hardbound, ISBN: 0-444-98874-2, 726 pages, publication date: 1989
Imprint: ELSEVIER


HALITE SALTERN IN THE CANNING BASIN, WESTERN-AUSTRALIA - A SEDIMENTOLOGICAL ANALYSIS OF DRILL CORE FROM THE ORDOVICIAN-SILURIAN MALLOWA SALT, 1992, Cathro Dl, Warren Jk, Williams Ge,
The Late Ordovician-Early Silurian Mallowa Salt of the Carribuddy Group, Canning Basin, north-west Australia, is the largest halite deposit known in Australia, attaining thicknesses of 800 m or more within an area of approximately 200 000 km2. Study of 675 m of drill core from BHP-Utah Minerals' Brooke No. 1 well in the Willara Sub-basin indicates that the Mallowa Salt accumulated within a saltern (dominantly subaqueous evaporite water body) that was subject to recurrent freshening, desiccation and exposure. Textures and bromine signatures imply a shallow water to ephemeral hypersaline environment typified by increasing salinity and shallowing into evaporitic mudflat conditions toward the top of halite-mudstone cycles (Type 2) and the less common dolomite/anhydrite-halite-mudstone cycles (Type 1). The borate mineral priceite occurs in the capping mudstones of some cycles, reinforcing the idea of an increasing continental influence toward the top of mudstone-capped halite cycles. The rock salt in both Type 1 and Type 2 cycles typically comprises a mosaic of large, randomly orientated, interlocking halite crystals that formed during early diagenesis. It only partially preserves a primary sedimentary fabric of vertically elongate crystals, some with remnant aligned chevrons. Intraformational hiati, halite karst tubes and solution pits attest to episodic dissolution. Stacked Type 2 cycles dominate; occasional major recharges of less saline, perhaps marine, waters in the same area produced Type 1 cycles. The envisaged saltern conditions were comparable in many ways to those prevailing during the deposition of halite cycles of the Permian Salado Formation in New Mexico and the Permian San Andres Formation of the Palo Duro Basin area in Texas. However, in the Canning Basin the cycles are characterized by a much lower proportion of anhydrite, implying perhaps a greater degree of continental restriction to the basin. The moderately high level of bromine in the Mallowa Salt (156.5 43.5 ppm Br for primary halite, 146.1 54.7 ppm Br for secondary halite) accords with evolved continental brines, although highly evaporative minerals such as polyhalite and magnesite are absent. The bromine levels suggest little or no dissolution/reprecipitation of primary halite and yet, paradoxically, there is little preservation of the primary depositional fabric. The preservation of early halite cements and replacement textures supports the idea of an early shutdown of brine flow paths, probably at burial depths of no more than a few metres, and the resultant preservation of primary bromine values in the secondary halite

DISLOCATION OF THE EVAPORITIC FORMATIONS UNDER TECTONIC AND DISSOLUTION CONTROLS - THE MODEL OF THE DINANTIAN EVAPORITES FROM VARISCAN AREA (NORTHERN FRANCE AND BELGIUM), 1993, Rouchy J. M. , Groessens E. , Laumondais A. ,
Within the Franco-Belgian segment of the Hercynian orogen, two thick Dinantian anhydritic formations are known, respectively in the Saint-Ghislain (765 m) and Epinoy 1 (904 m) wells. Nevertheless, occurrences of widespread extended breccias and of numerous pseudomorphs of gypsum/anhydrite in stratigraphically equivalent carbonate deposits (boreholes and outcrops), suggest a larger extent of the evaporitic conditions (fig. 1, 2). The present distribution of evaporites is controlled by palaeogeographical differentiation and post-depositional parameters such as tectonics and dissolution. These latter have dissected the deposits formerly present in all the structural units. By using depositional, diagenetic and deformational characters of these formations, the article provides a model for the reconstruction of a dislocated evaporitic basin. This segment of the Hercynian chain is schematically composed of two main units (fig. 1, 3) : (1) the autochthonous or parautochthonous deposits of the Namur synclinorium, (2) the Dinant nappe thrusted northward over the synclinorium of Namur. The major thrust surface is underlined by a complex fault bundle (faille du Midi) seismically recognized over more than 100 km. A complex system of thrust slices occurs at the Hercynian front. Except for local Cretaceous deposits, most of the studied area has been submitted to a long period of denudation since the Permian. Sedimentary, faunistic and geochemical data argue for a marine origin of the brines which have generated the evaporites interbedded with marine limestones. Sedimentary structures. - The thick evaporitic formations are composed of calcium-sulfates without any clear evidence of the former presence of more soluble salts (with the exception of a possible carbonate-sulfate breccia in the upper part of the Saint-Ghislain formation). As in all the deeply buried evaporitic formations, the anhydrite is the main sulfate component which displays all the usual facies : pseudomorphs after gypsum (fig. 4A, B), nodular and mosaic (fig. 4C), laminated. The gypsum was probably an important component during the depositional phase despite the predominant nodular pattern of the anhydrite. Early diagenetic nodular anhydrite may have grown during temporary emersion of the carbonates (sabkha environments), but this mechanism cannot explain the formation of the whole anhydrite. So, most of the anhydrite structures result from burial-controlled gypsum --> anhydrite conversion and from mechanical deformations. Moreover, a complex set of diagenetic processes leads to various authigenic minerals (celestite, fluorite, albite, native sulfur, quartz and fibrous silica) and to multistaged carbonate <> sulfate replacements (calcite and dolomite after sulfate, replacive anhydrite as idiomorphic poeciloblasts, veinlets, domino-like or stairstep monocrystals...). These mineral transformations observed ill boreholes and in outcrops have diversely been controlled during the complex evolution of the series as : depositional and diagenetic pore-fluid composition, pressure and temperature changes with burial, bacterial and thermochemical sulfate reduction, deep circulations favored by mechanical brecciation, mechanical stresses, role of groundwater during exhumation of the series. Deformational structures. - A great variety of deformational structures as rotational elongation, stretching, lamination, isoclinal microfolding, augen-like and mylonitic structures are generated by compressive tectonic stresses (fig. 4D to J). The similarities between tectonic-generated structures and sedimentary (lamination) or diagenetic (pseudo-nodules) features could lead lo misinterpretations. The calcareous interbeds have undergone brittle deformation the style and the importance of which depend of their relative thickness. Stretching, boudins, microfolds and augen structures F, H. I) affect the thin layers while thicker beds may be broken as large fractured blocks dragged within flown anhydrite leading to a mylonitic-like structure (fig, 4G). In such an inhomogeneous formation made of interlayered ductile (anhydrite) and brittle (carbonate) beds, the style and the intensity of the deformation vary with respect to the relative thickness of each of these components. Such deformational features of anhydrite may have an ubiquitous significance and can result either from compressive constraints or geostatic movements (halokinesis). Nevertheless, some data evidence a relation with regional tangential stresses: (1) increase of the deformation toward the bottom of the Saint-Ghislain Formation which is marked by a deep karst suggesting the presence of a mechanical discontinuity used as a drain for dissolving solutions (fig. 3, 4); (2) structural setting (reversed series, internal slidings) of the Epinoy 1 formation under the Midi thrust. However, tectonic stresses also induce flowing deformations which have contributed to cause their present discontinuity. It can be assumed that the evaporites played an active role for the buckling of the regional structure as detachment or gliding layers and more specifically for the genesis of duplex structures. Breccia genesis. - Great breccia horizons are widely distributed in outcrops as well as in the subsurface throughout the greater part of the Dinant and Namur units (fig. 2). The wide distribution of pseudomorphosed sulfates in outcrops and the stratigraphical correlation between breccia and Saint-Ghislain evaporitic masses (fig. 2) suggest that some breccia (although not all) have been originated from collapse after evaporites solution. Although some breccia may result from synsedimentary dissolution, studied occurrences show that most of dissolution processes started after the Hercynian deformation and, in some cases, were active until recently : elements made of lithified and fractured limestones (Llandelies quarries) (fig. 5A), preservation of pseudomorphs of late replacive anhydrite (Yves-Gomezee) (fig. 5B, C), deep karst associated with breccia (Douvrain, Saint Ghislain, Ghlin boreholes) (fig. 3, 4, 5D)). Locally, the final brecciation may have been favored by a mechanical fragmentation which controlled water circulations (fig. 5E). As postulated by De Magnee et al. [19861, the dissolution started mostly after the Permian denudation and continued until now in relation with deep circulations and surface weathering (fig. 6). So, the above-mentioned occurrences of the breccia are logically explained by collapse after dissolution of calcium-sulfates interbeds of significant thickness (the presence of salt is not yet demonstrated), but other Visean breccia may have a different origin (fig. 5F). So, these data prove the extension of thick evaporitic beds in all the structural units including the Dinant nappe, before dissolution and deformation. Implications. - Distribution of Visean evaporites in northern France and Belgium is inherited from a complicated paleogeographic, tectonic and post-tectonic history which has strongly modified their former facies, thicknesses and limits (fig. IA, 6). Diversified environments of deposition controlled by both a palaeogeographical differentiation and water level fluctuations led to the deposition of subaqueous (gypsum) or interstitial (gypsum, anhydrite) crystallization. Nevertheless, most of the anhydrite structures can be interpreted as resulting from burial conversion of gypsum to anhydrite rather than a generalized early diagenesis in sabkha-like conditions. Deformation of anhydrite caused by Hercynian tangential stresses and subsequent flow mechanisms, have completed the destruction of depositional and diagenetic features. The tectonic deformations allow us to consider the role of the evaporites in the Hercynian deformations. The evaporites supplied detachment and gliding planes as suggested for the base of the Saint-Ghislain Formation and demonstrated by the structural setting of Epinoy 1 evaporites in reverse position and in a multi-system of thrust-slices below the Midi overthrust (fig. 7). So, although the area in which evaporation and precipitation took place cannot be exactly delineated in geographic extent, all the data evidence that the isolated thick anhydritic deposits represent relics of more widespread evaporites extending more or less throughout the different structural units of this Hercynian segment (fig. 1B). Their present discontinuity results from the combination of a depositional differentiation, mechanical deformations and/or dissolution

Management of some unusual features in the show caves of the United States., 1994, Gurnee Jeanne
Protection of the unusual features in some of the 200 show caves of the U.S. have required innovative management. The sea caves of both the east and west coasts present the need for special preservation methods. Throughout the nation sometimes glass enclosures, vehicles and boats are used to separate visitors from sensitive cave features. Lighting and cleaning techniques have been studied and altered to discourage growth of algae. Some show caves are protected by double glass entrance and exit doors. Many caves, particularly on public lands, are closed during the hibernation period of endangered bats. In a number of caves, Native Americans have left artifacts and other evidences of their early visits. which have either been preserved in situ or relocated at appropriate archival sites. The paper gives in more details specific caves and methods for the preservation of particular unique features.

ASSOCIATION OF TEPEES AND PALEOKARST IN THE LADINIAN CALCARE-ROSSO (SOUTHERN ALPS, ITALY), 1994, Mutti M. ,
The Ladinian Calcare Rosso of the Southern Alps provides a rare opportunity to examine the temporal relationships between tepees and palaeokarst. This unit comprises peritidal strata pervasively deformed into tepees, repeatedly capped by palaeokarst surfaces mantled by terra rossa. Palaeokarsts, characterized by a regional distribution across the Southern Alps, occur at the base and at the top of the unit. Local palaeokarsts, confined to this part of the platform, occur within the Calcare Rosso and strongly affected depositional facies. Tepee deformation ranges from simple antiformal structures (peritidal tepecs) to composite breccias floating in synsedimentary cements and internal sediments (senile tepees). Peritidal tepees commonly occur at the top of one peritidal cycle, in association with subaerial exposure at the cycle top, while senile tepees affect several peritidal cycles, and are always capped by a palaeokarst surface. Cements and internal sediments form up to 80% of the total rock volume of senile tepees. The paragenesis of senile tepees is extremely complex and records several, superimposed episodes of dissolution, cement precipitation (fibrous cements, laminated crusts, mega-rays) and deposition of internal sediments (marine sediment and terra rossa). Petrographical observations and stable isotope geochemistry indicate that cements associated with senile tepees precipitated in a coastal karstic environment under frequently changing conditions, ranging from marine to meteoric, and were altered soon after precipitation in the presence of either meteoric or mixed marine/meteoric waters. Stable isotope data for the cements and the host rock show the influence of meteoric water (average deltaO-18 = - 5.8 parts per thousand), while strontium isotopes (average Sr-87/Sr-86 = 0.707891) indicate that cements were precipitated and altered in the presence of marine Triassic waters. Field relationships, sedimentological associations and paragenetic sequences document that formation of senile tepees was coeval with karsting. Senile tepees formed in a karst-dominated environment in the presence of extensive meteoric water circulation, in contrast to previous interpretations that tepees formed in arid environments, under the influence of vadose diagenesis. Tepees initiated in a peritidal setting when subaerial exposure led to the formation of sheet cracks and up-buckling of strata. This porosity acted as a later conduit for either meteoric or mixed marine/meteoric fluids, when a karst system developed in association with prolonged subaerial exposure. Relative sea level variations, inducing changes in the water table, played a key role in exposing the peritidal cycles to marine, mixed marine/meteoric and meteoric diagenetic environments leading to the formation of senile tepees. The formation and preservation in the stratigraphic record of vertically stacked senile tepees implies that they formed during an overall period of transgression, punctuated by different orders of sea level variations, which allowed formation and later freezing of the cave infills

Emplacement and preservation of vertebrates in caves and fissures, 1994, Simms Michael J. ,
The sediments filling underground cavities and open fissures represent a major source of fossil vertebrate remains. The significance of such sites is disproportionate to the relatively small volume of sediment which they contain, and arises from the enhanced preservation, compared with surface sites, of both bones and sediments and the operation of one or more concentrative processes. Isolation of vertebrate material from temperature and humidity changes, scavenging and soil organisms greatly increases their preservation potential. Three main types of concentrative mechanism can be recognized: where the animals lived and died in that environment (biotic autochthonous); where the animal remains were transported into that environment by some biotic agency, such as a predator (biotic allochthonouns); and where the animal remains were introduced into that environment as a result of some abiotic process, such as flooding (abiotic allochthonous). The precise mechanism operating in a particular case may be deduced from a consideration of faunal composition, taphonomic criteria and geomorphological and sedimentological contexts, with each concentrative process being characterized by a distinctive combination of these

The Speleothem medium of finger flutings and its isotopic geochemistry., 1995, Bednarik Robert G.
The isotopic geochemistry relating to the re-precipitation of calcite in caves is considered, in terms of its theory, natural manifestations, and relationship with questions of radiometric dating of carbonate speleothems. Specific forms of' such deposits are considered, together with the various modification processes they are subjected to. More specifically, particular forms of rock art found within, as well as on or under such deposits are examined, such as finger flutings commonly found in caves of Europe and Australia. Some of the variables relating to their occurrence are elucidated, their preservation and possible dating is reviewed in the light of these factors, and new radiometric data from South Australian caves are introduced and discussed.

BACTERIA, FUNGI AND BIOKARST IN LECHUGUILLA CAVE, CARLSBAD-CAVERNS-NATIONAL-PARK, NEW-MEXICO, 1995, Cunningham Ki, Northup De, Pollastro Rm, Wright Wg, Larock Ej,
Lechuguilla Cave is a deep, extensive, gypsum- and sulfur-bearing hypogenic cave in Carlsbad Caverns National Park, New Mexico, most of which (> 90%) lies more than 300 m beneath the entrance. Located in the arid Guadalupe Mountains, Lechuguilla's remarkable state of preservation is partially due to the locally continuous Yates Formation siltstone that has effectively diverted most vadose water away from the cave. Allocthonous organic input to the cave is therefore very limited, but bacterial and fungal colonization is relatively extensive: (1) Aspergillus sp. fungi and unidentified bacteria are associated with iron-, manganese-, and sulfur-rich encrustations on calcitic folia near the suspected water table 466 m below the entrance; (2) 92 species of fungi in 19 genera have been identified throughout the cave in oligotrophic (nutrient-poor) ''soils'' and pools; (3) cave-air condensate contains unidentified microbes; (4) indigenous chemoheterotrophic Seliberius and Caulobacter bacteria are known from remote pool sites; and (5) at least four genera of heterotrophic bacteria with population densities near 5 x 10(5) colony-forming units (CFU) per gram are present in ceiling-bound deposits of supposedly abiogenic condensation-corrosion residues. Various lines of evidence suggest that autotrophic bacteria are present in the ceiling-bound residues and could act as primary producers in a unique subterranean microbial food chain. The suspected autotrophic bacteria are probably chemolithoautotrophic (CLA), utilizing trace iron, manganese, or sulfur in the limestone and dolomitic bedrock to mechanically (and possibly biochemically) erode the substrate to produce residual floor deposits. Because other major sources of organic matter have not been detected, we suggest that these CLA bacteria are providing requisite organic matter to the known heterotrophic bacteria and fungi in the residues. The cavewide bacterial and fungal distribution, the large volumes of corrosion residues, and the presence of ancient bacterial filaments in unusual calcite speleothems (biothems) attest to the apparent longevity of microbial occupation in this cave

Bibliography of Belizean Caving, 1996, Williams, Nick
Approximately 300 caves have been documented in Belize in the past 100 years. These include 198 registered archaeological sites. Ethnohistoric, ethnographic, iconographic, and archaeological sources indicate the importance of caves in Maya culture over a period spanning at least 1,500 years. The few analyses of ceramics from Belize caves indicate use predominantly during the Late/Terminal Classic and Early Postclassic (A.D. 600-1100). A wide array of archaeological evidence such as ceremonial dumps, burials, art, and artificial construction support the idea that caves were used primarily for ceremonial activities. Looting is a major problem, and lack of funding seriously compromises not only the protection of cave sites, but also the preservation of materials and publication of the information recovered by archaeological research.

A tentative classification of paleoweathering formations based on geomorphological criteria, 1996, Battiauqueney Y,
A geomorphological classification is proposed that emphasizes the usefulness of paleoweathering records in any reconstruction of past landscapes. Four main paleoweathering records are recognized: 1. Paleoweathering formations buried beneath a sedimentary or volcanic cover. Most of them are saprolites, sometimes with preserved overlying soils. Ages range from Archean to late Cenozoic times; 2. Paleoweathering formations trapped in karst: some of them have buried pre-existent karst landforms, others have developed simultaneously with the subjacent karst; 3. Relict paleoweathering formations: although inherited, they belong to the present landscape. Some of them are indurated (duricrusts, silcretes, ferricretes,...); others are not and owe their preservation to a stable morphotectonic environment; 4. Polyphased weathering mantles: weathering has taken place in changing geochemical conditions. After examples of each type are provided, the paper considers the relations between chemical weathering and landform development. The climatic significance of paleoweathering formations is discussed. Some remote morphogenic systems have no present equivalent. It is doubtful that chemical weathering alone might lead to widespread planation surfaces. Moreover, classical theories based on sea-level and rivers as the main factors of erosion are not really adequate to explain the observed landscapes

Late Wisconsinan deglaciation of Alberta: Processes and paleogeography, 1996, Mandryk C. A. S. ,
The scarcity of lake basins in Alberta dating earlier than 11,000 BP has been interpreted as indicating the continued presence of active glacial ice. Because of the related implication that the presence of ice precludes the existence of an ice-free corridor, it is useful to examine this issue more closely. Due to the effects of deglaciation, many areas of Alberta were dominated by chaotic ice-stagnation conditions, with continual reversal of topography and rapid transformation of the surface. The dynamic nature of the environment affects arguments regarding the existence of an ice-free corridor as well as having implications for archeological site formation, preservation and discovery. Deglaciation models utilizing paradigms of active ice retreat may result in dichotomous depictions of the land surface as either ice covered or deglaciated. Due to the insulating properties of supraglacial debris, stagnant ice results in a situation that is simultaneously neither and both of the above conditions. While the landscape is ice covered and thus not 'ice-free', an accessible landscape characterized by glacial karst topography exists on top of the stagnating ice surface. General reconstructions of the impact of stagnant ice and glacial karst topography on the paleogeography of Alberta are presented for discussion. Copyright (C) 1996 INQUA/Elsevier Science Ltd

Thermodynamic equilibrium, kinetics, activation barriers, and reaction mechanisms for chemical reactions in Karst Terrains, 1997, White W. B. ,
Chemical reactions pertinent to karst systems divide broadly into (a) speciation reactions within aqueous solutions, (b) dissolution/precipitation and other acid/base reactions between aqueous solutions and solid minerals, and (c) redox reactions involving various carbon and sulfur-bearing species. As a backdrop against which other chemistry can be evaluated, selected phase diagrams and equilibrium speciation diagrams were calculated for the system Ca--Mg--O--H--C--S. The kinetics of reactions within this system span time scales from milliseconds for homogeneous reactions in solution through hundreds of hours for carbonate mineral dissolution reactions, to geologic time scales for reactions such as the aragonite/calcite inversion or the oxidation/reduction of native sulfur. In purely inorganic systems, kinetic barriers, typically on the order of tens of kJ/mole, are set by nucleation processes and by activated complex formation. Biological processes impact the purely inorganic chemistry by the following mechanisms: (a) Secretions and waste products from biological activity or consumption of CO2 by organisms changes the chemistry in the microenvironments of reaction surfaces. Oxidation potentials, pH, and ion activities may be modified, thus shifting equilibria. (b) Reaction rates may be increased due to modification of activated complexes and thus the activation barriers to reaction. (c) Organic compounds or microorganisms may act as substrates, thus lowering nucleation barriers. The preservation of microorganisms in cave deposits does not necessarily prove a cause and effect relationship

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