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Articles 1171 - 1200 of 1881

Full-Text Articles in Earth Sciences

Mammut Borsoni (Hays 1834) From The Early Pliocene Of Husnicioara (Mehedinţi District, Romania), Vlad Codrea, Florina Diaconu Feb 2008

Mammut Borsoni (Hays 1834) From The Early Pliocene Of Husnicioara (Mehedinţi District, Romania), Vlad Codrea, Florina Diaconu

Studia UBB Geologia

A mastodon tooth has been found at Husnicioara coal open pit, in Mehedinţi district (southwestern Romania). It originates from the Lower Pliocene (Dacian) gravel and sand deposits lying just above the coal bed IV, mined in this quarry. The tooth exposing zygodont features undoubtedly belongs to Mammut borsoni (“Borson’s mastodont”). Although this species is very common in the Pliocene vertebrate faunas from this part of Europe, until now it was missing from the Lower Pliocene (Dacian) assemblage’s lists in our country.

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On The Cretaceous Occurrences Of Ammogloborotalia Zheng, 2001 (Foraminifera), Michael A. Kaminski, Claudia Cetean, Andrew Henderson, Sorin Filipescu Feb 2008

On The Cretaceous Occurrences Of Ammogloborotalia Zheng, 2001 (Foraminifera), Michael A. Kaminski, Claudia Cetean, Andrew Henderson, Sorin Filipescu

Studia UBB Geologia

Three species of agglutinated foraminifera from Cretaceous deep-water deposits that have been described as trochamminids are here transferred to the genus Ammogloborotalia ZHENG, 2001. These species are Trochammina abrupta GEROCH, 1959; Trochammina quinqueloba GEROCH, 1959, and Ammoanita globorotaliaeformis Gradstein and Kaminski, 1999. A fourth species, Ammogloborotalia sp.1, which is probably a new species from the Turonian of the southern East Carpathians of Romania is reported here for the first time. We hereby extend the known stratigraphic range of the genus Ammogloborotalia to the Late Jurassic (Tithonian).

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What Is Cczn-Armalcolite? A Crystal-Chemical Discussion And An Ad-Hoc Incursion In The Crichtonite-Minerals Group, Gavril Sabau, Augusta Alberico Feb 2008

What Is Cczn-Armalcolite? A Crystal-Chemical Discussion And An Ad-Hoc Incursion In The Crichtonite-Minerals Group, Gavril Sabau, Augusta Alberico

Studia UBB Geologia

The status of CCZN-armalcolite, commonly still believed to be a variety of armalcolite s.s., is questionable in view of partial evidence suggesting that it would represent a distinct phase, as initially claimed by its discoverers. Because of the rarity of the mineral, combined with its habitual small grain-size, no successful structural investigation could be undertaken so far. Therefore we attempted a chemical overview of existing and original data pertaining to CCZN-armalcolite. With the view of systematizing structure-composition relationships, we analyzed the topology of large cations – bearing close-packed oxides, while extending the nomenclature in use in order to accommodate further …

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Uppermost Jurassic-Lower Cretaceous Carbonate Deposits From Fara San Martino (Maiella, Italy): Biostratigraphic Remarks, Roberta Bruni, Ioan I. Bucur, Alain Preat Feb 2008

Uppermost Jurassic-Lower Cretaceous Carbonate Deposits From Fara San Martino (Maiella, Italy): Biostratigraphic Remarks, Roberta Bruni, Ioan I. Bucur, Alain Preat

Studia UBB Geologia

The Uppermost Jurassic-Lower Cretaceous limestone succession in the Maiella region of Italy has been investigated in a profile covering more than 400 m stratigraphical thickness at Fara San Martino. The succession mainly consists of peritidal limestones, intertidal and supratidal sequences being dominant, together with subtidal lagoonal facies. As a consequence, the microfossil assemblages are generally poorly developed, Microfossils occur within the subtidal lagoonal facies of this suite of restricted sediments. This feature led us to recognise five informal biostratigraphic intervals, which are facies related – instead of biozones, each of the intervals being characterized by specific micropaleontological associations. The occurrence …

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Biostratigraphy Of The Cretaceous Deposits In The Western Transylvanides From Ampoi Valley (Southern Apuseni Mountains, Romania), Ramona Balc, Erika Suciu-Krausz, Florin Borbei Feb 2008

Biostratigraphy Of The Cretaceous Deposits In The Western Transylvanides From Ampoi Valley (Southern Apuseni Mountains, Romania), Ramona Balc, Erika Suciu-Krausz, Florin Borbei

Studia UBB Geologia

The present study is an approach of the issues related to the biostratigraphy of the Western Transylvanides. The research provided exact age data for the Feneş Formation, Valea lui Paul Formation, Bozeş Formation and Râmeţi Formation. The age of the formations was established based on the calcareous nannoplankton assemblages in Barremian-Campanian range. The lithological features together with the new age data allowed us to modify the boundaries between formations; accordingly the knowledge on the structure of South Apuseni Mountains required changes, too. The new data also imply the modification of the existent geological maps of the region. Based on the …

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Early Medieval Ceramics From The Viile Tecii Archaeological Site (Romania): An Optical And Xrd Study, Corina Ionescu, Lucretia Ghergari, Marius Horga, Gabriela Rădulescu Feb 2008

Early Medieval Ceramics From The Viile Tecii Archaeological Site (Romania): An Optical And Xrd Study, Corina Ionescu, Lucretia Ghergari, Marius Horga, Gabriela Rădulescu

Studia UBB Geologia

Mineralogical and petrographic studies of Early Medieval potshards exhumed in the Viile Tecii archaeological site (North Transylvania, Romania) show a ceramic body composed of a microcrystalline to amorphous matrix, various clasts and voids. The microscopical features and XRD patterns indicate that illitic-kaolinitic clays were used as raw materials, together with quartzitic sands as tempering material. The ceramic vessels were obtained with the potter’s wheel, but the fabric is only slightly oriented, due either to the fast modeling or to the coarseness of the clayish paste. The thermal alteration of mineral phases points to relatively high firing-temperatures, between 800 and 900°C.

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The Sarmatian Vertebrates From Draxeni (Moldavian Platform), Vlad Codrea, Laurentiu Ursachi Feb 2008

The Sarmatian Vertebrates From Draxeni (Moldavian Platform), Vlad Codrea, Laurentiu Ursachi

Studia UBB Geologia

Middle Miocene (Sarmatian) vertebrates had been unearthed at Draxeni (Vaslui district). The site is located in the northern area of the Moldavian Platform. There, the sand belonging to Şcheia Formation (Bessarabian) is mined in a restricted open pit. This sand is related to a littoral environment (shoreface and foreshore). Some of its levels are rich in mollusc debris. Vertebrate remains, carried into the Bessarabian brackish basin are present too, but in smaller amounts. Mastodon, rhinoceros, hipparionine, tortoise remains had been collected there over several years. All teeth and bones are isolated and bear the marks of intensive rolling by waves …

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Petrology And Geochemistry Of The Muntele Mare Granitoid (Northern Apuseni Mountains), Romania, Lucretia Ghergari, Cristina Maris Feb 2008

Petrology And Geochemistry Of The Muntele Mare Granitoid (Northern Apuseni Mountains), Romania, Lucretia Ghergari, Cristina Maris

Studia UBB Geologia

The paper brings new data on the petrography and geochemistry of the Muntele Mare Granitoid (MMG), from its northernmost outcropping area (Mănăstireni-Bedeci area, Gilău Massif, Apuseni Mountains), where MM\G is are actively quarried for quartz and feldspar that are used in the ceramics industry. The MMG mined in the Bedeci quarry has a pegmatitic hypidiomorphous – inequigranular fabric, and a low melanocratic index (ca. 7%). It consists of quartz, plagioclase (two generations: acidic andesine-basic oligoclase (34-35% An), and albite (9-11% An)), orthoclase ± perthite in various substitution stages by microcline (intermediary), as well as microcline maximum, muscovite and biotite. Accessories …

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High-Temperature And “Exotic” Minerals From The Cioclovina Cave, Romania: A Review, Bogdan P. Onac, Herta S. Effenberger, Radu C. Breban Feb 2008

High-Temperature And “Exotic” Minerals From The Cioclovina Cave, Romania: A Review, Bogdan P. Onac, Herta S. Effenberger, Radu C. Breban

Studia UBB Geologia

This paper reports on the identification of four rare minerals in the phosphate deposit in Cioclovina Cave, Romania. Berlinite, AlPO4 and hydroxylellestadite, Ca5[(Si,P,S)O4]3(OH,F,Cl) are minerals that can form only at high temperatures, and would not be expected in a sedimentary environment. In this study we review the characteristics of berlinite and hydroxylellestadite from a heated sedimentary sequence in Cioclovina Cave (Romania) and refine their structure from single-crystal X-ray data. Two other minerals, churchite-(Y), YPO4⋅2H2O and foggite, CaAl(PO4)(OH)2⋅H2O are, for the first time, described from a cave environment. The minerals were documented by means of single-crystal X-ray investigations, X-ray powder diffraction, …

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Rethinking Early Earth Phosphorus Geochemistry, Matthew A. Pasek Jan 2008

Rethinking Early Earth Phosphorus Geochemistry, Matthew A. Pasek

School of Geosciences Faculty and Staff Publications

Phosphorus is a key biologic element, and a prebiotic pathway leading to its incorporation into biomolecules has been difficult to ascertain. Most potentially prebiotic phosphorylation reactions have relied on orthophosphate as the source of phosphorus. It is suggested here that the geochemistry of phosphorus on the early Earth was instead controlled by reduced oxidation state phosphorus compounds such as phosphite (HPO3 2−), which are more soluble and reactive than orthophosphates. This reduced oxidation state phosphorus originated from extraterrestrial material that fell during the heavy bombardment period or was produced during impacts, and persisted in the mildly reducing atmosphere. …

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Locating Suitable Habitats For West Nile Virus-Infected Mosquitoes Through Association Of Environmental Characteristics With Infected Mosquito Locations: A Case Study In Shelby County, Tennessee, Esra Ozdenerol, Elzbieta Bialkowska-Jelinska, Gregory N. Taff Jan 2008

Locating Suitable Habitats For West Nile Virus-Infected Mosquitoes Through Association Of Environmental Characteristics With Infected Mosquito Locations: A Case Study In Shelby County, Tennessee, Esra Ozdenerol, Elzbieta Bialkowska-Jelinska, Gregory N. Taff

School of Geosciences Student Publications

Background: Since its first detection in 2001, West Nile Virus (WNV) poses a significant health risk for residents of Shelby County in Tennessee. This situation forced public health officials to adopt efficient methods for monitoring disease spread and predicting future outbreaks. Analyses that use environmental variables to find suitable habitats for WNV-infected mosquitoes have the potential to support these efforts. Using the Mahalanobis Distance statistic, we identified areas of Shelby County that are ecologically most suitable for sustaining WNV, based on similarity of environmental characteristics to areas where WNV was found. The environmental characteristics in this study were based on …

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The Role Of The Epikarst In Karst And Cave Hydrogeology: A Review, Paul W. Williams Jan 2008

The Role Of The Epikarst In Karst And Cave Hydrogeology: A Review, Paul W. Williams

International Journal of Speleology

The epikarst (also known as the subcutaneous zone) comprises highly weathered carbonate bedrock immediately beneath the surface or beneath the soil (when present) or exposed at the surface. Porosity and permeability are higher near the surface than at depth, consequently after recharge percolating rainwater is detained near the base of the epikarst, the detention ponding producing an epikarstic aquifer. Such an aquifer is found only where the uppermost part of the vadose zone is very weathered compared to the bedrock at depth. Sometimes this contrast in porosity and permeability does not occur either because the epikarst has been scraped off …

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Contribution Of Artificial Galleries To The Knowledge Of Karstic System Behaviour In Addition To Natural Cavern Data, Benjamin Garry, Thibaut Blondel, Christophe Emblanch, Christophe Sudre, Séverine Bilgot, Alain Cavaillou, Daniel Boyer, Michel Auguste Jan 2008

Contribution Of Artificial Galleries To The Knowledge Of Karstic System Behaviour In Addition To Natural Cavern Data, Benjamin Garry, Thibaut Blondel, Christophe Emblanch, Christophe Sudre, Séverine Bilgot, Alain Cavaillou, Daniel Boyer, Michel Auguste

International Journal of Speleology

The study of karstic systems is mainly based on hydrodynamic and hydrochemical data collected at system inlets (rainfall) and outlets (springs). Indeed, some complementary data base coming from speleological and hydrogeological explorations of natural cavities exist. However, they are not completely representative of all the types of flows. These kinds of flow which have a large part in general hydrodynamics of a system are already the result of a structured organization of karst due to complex phenomena of limestone dissolution. Artificial galleries have the advantage to be easily accessible. Moreover, they cut randomly flows which are much less structured or …

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Tracer Tests In Karst Hydrogeology And Speleology, Nico Goldscheider, Joe Meiman, Michiel Pronk, Christopher Smart Jan 2008

Tracer Tests In Karst Hydrogeology And Speleology, Nico Goldscheider, Joe Meiman, Michiel Pronk, Christopher Smart

International Journal of Speleology

This article presents an introduction to the fundamentals of tracing techniques and their application in cave and karst environments, illustrated by case studies from the Mammoth Cave, USA, and a small experimental site in Switzerland. The properties and limitations of the most important artificial tracers are discussed, and the available methods of tracer injection, sampling, online monitoring and laboratory analysis are presented. Fully quantitative tracer experiments result in continuous or discrete concentration-time data series, i.e. breakthrough curves, and concomitant discharge data, which make it possible to obtain detailed information about groundwater flow and contaminant transport. Within the frame of speleological …

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Epigene And Hypogene Gypsum Karst Manifestations Of The Castile Formation: Eddy County, New Mexico And Culberson County, Texas, Usa, Kevin W. Stafford, Raymond Nance, Laura Rosales-Lagarde, Penelope J. Boston Jan 2008

Epigene And Hypogene Gypsum Karst Manifestations Of The Castile Formation: Eddy County, New Mexico And Culberson County, Texas, Usa, Kevin W. Stafford, Raymond Nance, Laura Rosales-Lagarde, Penelope J. Boston

International Journal of Speleology

Permian evaporites of the Castile Formation crop out over ~1,800 km2 in the western Delaware Basin (Eddy County, New Mexico and Culberson County, Texas, USA) with abundant and diverse karst manifestations. Epigene karst occurs as well-developed karren on exposed bedrock, while sinkholes dominate the erosional landscape, including both solutional and collapse forms. Sinkhole analyses suggest that more than half of all sinks are the result of upward stoping of subsurface voids, while many solutional sinks are commonly the result of overprinting of collapsed forms. Epigene caves are laterally limited with rapid aperture decreases away from insurgence, with passages developed …

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Annually Laminated Speleothems: A Review, Andy Baker, Claire L. Smith, Catherine Jex, Ian J. Fairchild, Dominique Genty, Lisa Fuller Jan 2008

Annually Laminated Speleothems: A Review, Andy Baker, Claire L. Smith, Catherine Jex, Ian J. Fairchild, Dominique Genty, Lisa Fuller

International Journal of Speleology

This review of annually laminated speleothems firstly considers the four types of annual laminae found within speleothems: fluorescent laminae formed by annual variations in organic matter flux; visible or petrographic laminae, formed by annual variations in calcite texture or fabric; calcite-aragonite couplets; and finally trace element laminae. The methods available to confirm the annual nature, or otherwise, of lamina deposition are reviewed. We consider the use of annual laminae in chronology building, with particular relevance to palaeoclimate reconstructions. Finally, the use of annual lamina width as a palaeoclimate proxy is reviewed.

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Groundwater Contamination In Caves: Four Case Studies In Spain, Monserrat Jiménez-Sánchez, Heather Stoll, Iñaki Vadillo, Manolo López-Chicano, María Domínguez-Cuesta, Wenceslao Martín-Rosales, Mónica Meléndez-Asensio Jan 2008

Groundwater Contamination In Caves: Four Case Studies In Spain, Monserrat Jiménez-Sánchez, Heather Stoll, Iñaki Vadillo, Manolo López-Chicano, María Domínguez-Cuesta, Wenceslao Martín-Rosales, Mónica Meléndez-Asensio

International Journal of Speleology

Groundwater quality was monitored in four Spanish caves using concentrations of nitrate, potassium, phosphorus and in some cases total organic carbon. Three of the caves are located in NW Spain and contain prehistoric cave paintings and hence have special conservation interest. Of these, two are open show caves (Tito Bustillo and Pindal Caves), while the other one (Herrerías Cave) is not managed for tours and is partially closed off to public access. The fourth cave (Las Maravillas Cave) is located in SW Spain and is opened to the public because of its geological features and natural beauty. In this paper, …

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Surface Corrosion Of An Alpine Karren Field: Recent Measures At Innerbergli (Siebenhengste, Switzerland), Philipp Häuselmann Jan 2008

Surface Corrosion Of An Alpine Karren Field: Recent Measures At Innerbergli (Siebenhengste, Switzerland), Philipp Häuselmann

International Journal of Speleology

29 year old rock paintings in the Alpine karren field of Innerbergli (Siebenhengste, Switzerland) prevented the underlying rock from corrosion, while the surface nearby was corroded. Measurement of the steps indicates an average recent corrosion rate of 0.014 (±0.007) mm/a. This denudation rate is very similar to those observed in other comparable places and with other means.

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Late Pleistocene Cryogenic Calcite Spherolites From The Malachitdom Cave (Ne Rhenish Slate Mountains, Germany): Origin, Unusual Internal Structure And Stable C-O Isotope Composition, Detlev Konrad Richter, Dana Felicitas Christine Riechelmann Jan 2008

Late Pleistocene Cryogenic Calcite Spherolites From The Malachitdom Cave (Ne Rhenish Slate Mountains, Germany): Origin, Unusual Internal Structure And Stable C-O Isotope Composition, Detlev Konrad Richter, Dana Felicitas Christine Riechelmann

International Journal of Speleology

Cryogenic calcites yielded U-series ages in the range from 15.61±0.20 ka to 14.48±0.12 ka, which is the youngest age obtained so far for this type of cryogenic cave carbonates in Europe. Most of these particles of the Malachitdom Cave (NE Brilon, Sauerland, North Rhine-Westphalia) are complex spherolites usually smaller than 1 cm. They show δ13C-values between –1 and –5 ‰ VPDB and δ18O-values ranging from –7 to –16 ‰ VPDB, the δ13C-values increase and the δ18O-values decrease from centre to border. The complex spherolites are interpreted to be formed in slowly freezing …

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Report Of A Three-Year Monitoring Programme At Heshang Cave, Central China, Chaoyong Hu, Gideon M. Henderson, Junhua Huang, Zhenghong Chen, Kathleen R. Johnson Jan 2008

Report Of A Three-Year Monitoring Programme At Heshang Cave, Central China, Chaoyong Hu, Gideon M. Henderson, Junhua Huang, Zhenghong Chen, Kathleen R. Johnson

International Journal of Speleology

Heshang Cave is situated in central China (30°27’N, 110°25’E; 294 m) in the middle reaches of the Yangtze Valley, a region strongly impacted by the East Asian Monsoon. It contains large annually-laminated Holocene and late Pleistocene stalagmites which capture past monsoon behaviour with seasonal resolution, and could enhance understanding of the amplitude and frequency of monsoon behaviour in different climate states. In this paper, we present results of a 3-year monitoring programme at Heshang. T loggers outside the cave agree closely with T data from nearby meteorological stations. T at the site of growth of the largest recovered stalagmite averages …

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Palaeoclimate Research In Villars Cave (Dordogne, Sw-France), Dominique Genty Jan 2008

Palaeoclimate Research In Villars Cave (Dordogne, Sw-France), Dominique Genty

International Journal of Speleology

Villars Cave is a typical shallow cave from South-West France (45.44°N; 0.78°E; 175 m asl) that has provided several speleothem palaeoclimatic records such as the millennial scale variability of the Last Glacial period and the Last Deglaciation. Monitoring the Villars cave environment over a 13-year period has helped in the understanding of the stable isotopic speleothem content and in the hydrology. For example, it was demonstrated that most of the calcite CaCO3 carbon comes from the soil CO2, which explains the sensitivity of the δ13C to any vegetation and climatic changes. Drip rate monitoring, carried …

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Some Applications Of Geochemical And Isotopic Techniques To Hydrogeology Of The Caves After Research In Two Sites (Nerja Cave-S Spain And Fourbanne System-French Jura), Jacques Mudry, Bartolomé Andreo, Arnaud Charmoille, Cristina Liñán, Francisco Carrasco Jan 2008

Some Applications Of Geochemical And Isotopic Techniques To Hydrogeology Of The Caves After Research In Two Sites (Nerja Cave-S Spain And Fourbanne System-French Jura), Jacques Mudry, Bartolomé Andreo, Arnaud Charmoille, Cristina Liñán, Francisco Carrasco

International Journal of Speleology

Caves constitute privileged sampling spots to investigate the hydrochemical behaviour of infiltration, but the representative nature of samples can limit their reach. Taking this into account many results can be obtained from chemistry of water sampled in the caves. Carbonate tracers enable to reconstruct the ‘history’ of drip water water, including rainfall and temperatures. Moreover, permanent drip waters prove durability of water stored in the unsaturated zone over the cave, and lags between rain inputs and drip output enable to evaluate transit time through the unsaturated zone. The comparison of input/output concentrations can also contribute to estimate the local water …

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The Environmental Features Of The Monte Corchia Cave System (Apuan Alps, Central Italy) And Their Effects On Speleothem Growth, L. Piccini, G. Zanchetta, R. N. Drysdale, J. Hellstrom, I. Isola, A. E. Fallick, G. Leone, M. Doveri, M. Mussi, F. Mantelli, G. Molli, L. Lotti, A. Roncioni, E. Regattieri, M. Meccheri, L. Vaselli Jan 2008

The Environmental Features Of The Monte Corchia Cave System (Apuan Alps, Central Italy) And Their Effects On Speleothem Growth, L. Piccini, G. Zanchetta, R. N. Drysdale, J. Hellstrom, I. Isola, A. E. Fallick, G. Leone, M. Doveri, M. Mussi, F. Mantelli, G. Molli, L. Lotti, A. Roncioni, E. Regattieri, M. Meccheri, L. Vaselli

International Journal of Speleology

The Monte Corchia cave system, one of the most famous and popular caves in Italy, has in recent times been the subject of investigation on its speleothems as paleoclimate archives. This paper describes the geology, geomorphology and water chemistry of the cave system with the aim to elucidate the processes that have generated these speleothems and the properties they contain that are so useful for paleoclimatology. Some general conclusions can be drawn: i) the Corchia system is a cave developed over different altitudes during progressive uplift of the mountain chain in which it is located, probably under drainage conditions very …

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Carbon Dioxide Concentration In Air Within The Nerja Cave (Malaga, Andalusia, Spain), Cristina Liñán, Iñaki Vadillo, Francisco Carrasco Jan 2008

Carbon Dioxide Concentration In Air Within The Nerja Cave (Malaga, Andalusia, Spain), Cristina Liñán, Iñaki Vadillo, Francisco Carrasco

International Journal of Speleology

From 2001 to 2005 the CO2 concentration of the air in the interior and exterior of the Nerja Cave was studied and its relation with the air temperature and visitor number. The average annual CO2 concentration outside of the cave is 320 ppmv, whilst inside, the mean concentration increases to 525 ppmv during autumn and winter, and in the order of 750 ppmv during spring and summer. The temporal variation of CO2 content in the air of the cave is strongly influenced by its degree of natural ventilation which is, in turn, determined by the difference between …

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Environmental Monitoring In The Mechara Caves, Southeastern Ethiopia: Implications For Speleothem Palaeoclimate Studies, Asfawossen Asrat, Andy Baker, Melanie J. Leng, John Gunn, Mohammed Umer Jan 2008

Environmental Monitoring In The Mechara Caves, Southeastern Ethiopia: Implications For Speleothem Palaeoclimate Studies, Asfawossen Asrat, Andy Baker, Melanie J. Leng, John Gunn, Mohammed Umer

International Journal of Speleology

The interpretation of palaeoclimate records in speleothems depends on the understanding of the modern climate of the region, the geology, the hydrology above the caves, and the within-cave climate. Monitoring within-cave climate variability, geochemistry of speleothem-forming drip waters, and associated surface and groundwater, provides a modern baseline for interpretation of speleothem palaeohydrological and palaeoclimate records. Here, we present results of such monitoring of the Mechara caves in southeastern Ethiopia, conducted between 2004 and 2007. Results show nearly constant within-cave climate (temperature and humidity) in all caves, which generally reflects the surface climate. Groundwater and surface water geochemistry is similar across …

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Hydrodynamic Aspect Of Caves, Mitja Prelovšek, Janez Turk, Franci Gabrovšek Jan 2008

Hydrodynamic Aspect Of Caves, Mitja Prelovšek, Janez Turk, Franci Gabrovšek

International Journal of Speleology

From a hydrological point of view, active caves are a series of connected conduits which drain water through an aquifer. Water tends to choose the easiest way through the system but different geological and morphological barriers act as flow restrictions. The number and characteristics of restrictions depends on the particular speleogenetic environment, which is a function of geological, geomorphological, climatological and hydrological settings. Such a variety and heterogeneity of underground systems has presented a challenge for human understanding for many centuries. Access to many underground passages, theoretical knowledge and recent methods (modeling, water pressure-resistant dataloggers, precise sensors etc.) give us …

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Hydrogeochemical Processes As Environmental Indicators In Drip Water: Study Of The Cueva Del Agua (Southern Spain), Angel Fernandez-Cortes, Jose Maria Calaforra, Francisco Sánchez-Martos Jan 2008

Hydrogeochemical Processes As Environmental Indicators In Drip Water: Study Of The Cueva Del Agua (Southern Spain), Angel Fernandez-Cortes, Jose Maria Calaforra, Francisco Sánchez-Martos

International Journal of Speleology

Karst caves exhibit a wide range of hydrological and hydrochemical responses to infiltration events, due to their physical heterogeneity in space and dynamic variability over time, and due to non-Gaussian inputs (rain) and outputs (discharge). This paper reviews different approaches of studying seepage water in caves, in order to understand the infiltration regimen in the non-saturated zone of karst areas. As an illustration, we describe a four-year study of the active carbonate-water system in the Cueva del Agua (Granada, southern Spain) that automatically logs the discharge from a stalactite. The results indicate that: (1) the drip water regime is not …

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The Origin Of The Bemaraha Tsingy (Madagascar), Márton Veress, Dénes Lóczy, Zoltán Zentai, Gábor Tóth, Roland Schläffer Jan 2008

The Origin Of The Bemaraha Tsingy (Madagascar), Márton Veress, Dénes Lóczy, Zoltán Zentai, Gábor Tóth, Roland Schläffer

International Journal of Speleology

On Madagascar the most representative occurrences of tsingy are at Ankarana and Bemaraha. The tsingy are built up of giant grikes developed along cracks as well as karren features of much smaller size which cover the surfaces between grikes. We investigated the Bemaraha tsingy of Madagascar (surveyed profiles, measured grike directions, etc.) in order to reconstruct their development. The observations indicate that the majority of grikes of the tsingy are created from caves formed under the karst water table and subsequently opened up to the surface. The predominant processes may have been downward progressing dissolution or the collapse of cave …

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An Investigation Of Meromixis In Cave Pools, Lechuguilla Cave, New Mexico, David B. Levy Jan 2008

An Investigation Of Meromixis In Cave Pools, Lechuguilla Cave, New Mexico, David B. Levy

International Journal of Speleology

Chemical characteristics of permanent stratification in cave pools (meromixis) may provide insight into the geochemical origin and evolution of cave pool waters. The objective of this study was to test the hypothesis that some pools in Lechuguilla Cave may be subject to ectogenic meromixis, where permanent chemical stratification is induced by input of relatively saline or fresh water from an external source. However, because organic C concentrations in Lechuguilla waters are low (typically < 1 mg L-1), biogenic meromixis resulting in O2(g)-depleted subsurface waters is not expected. Four pools at various depths below ground surface (0 m) were studied: (1) …

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Monitoring Climatological, Hydrological And Geochemical Parameters In The Père Noël Cave (Belgium): Implication For The Interpretation Of Speleothem Isotopic And Geochemical Time-Series, Sophie Verheyden, Dominique Genty, Guy Deflandre, Yves Quinif, Eduard Keppens Jan 2008

Monitoring Climatological, Hydrological And Geochemical Parameters In The Père Noël Cave (Belgium): Implication For The Interpretation Of Speleothem Isotopic And Geochemical Time-Series, Sophie Verheyden, Dominique Genty, Guy Deflandre, Yves Quinif, Eduard Keppens

International Journal of Speleology

Père Noël cave climatology (air and water temperature, PCO2), hydrology (drip rate, conductivity) and geochemistry of water and calcite deposits (δ18O, δ13C, Mg/Ca and Sr/Ca) where studied to better interpret stable isotopic and trace element variations of speleothems. Results of an automated monitoring station and of manual sampling between 1991 and 1998 have demonstrated the highly seasonal signal of drip rate, its control by water excess and rainfall, and, at a shorter scale to air pressure changes. The modern calcite deposit study suggests a relationship between cave calcite isotopic composition (δ18O and …

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