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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. ...

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That farangothes ipoyios thiavasis is see aisle.?

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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 juniper (Keyword) returned 9 results for the whole karstbase:
The vegetation of the high mountains of Crete - a revision and multivariate analysis, 2002, Bergmeier E,
The vegetation at elevations above 1,400 m in the south Aegean island of Crete (Greece) is studied and revised. By means of phytosociological classification (assisted by TWINSPAN) and ordination (Detrended correspondence analysis, DCA), the plant communities and abiotic (environmental, geographical) factors governing the variance in vegetation are described and discussed. The analyses are based on 492 sample plots from the three major mountain ranges of Crete. All published data available, as well as own unpublished releves are included. Since the plots differ much with respect to species number and plot size, and to combine different subsets and different data properties, various data sets are used for DCA ordination. Data on environmental variables are used supplementarily. Ordination results suggest the following factors to be of major effect on the variance in vegetation: Rock type, soil type, altitude, geographical situation, degree of substrate fixation, and inclination. The representation of local and regional endemics in the vegetation increases with altitude and along the habitat type series: phrygana and woodland - fixed slopes - dolines - screes. A synoptic table of 26 columns (vegetation types and subtypes) is presented. The vegetation consists of the tragacanth formation of fixed slopes (8 columns), swards and scrub of doline grounds (9), scree vegetation (4), and rupicolous chasmophytic vegetation (2). Phrygana (2) and woodland vegetation (1) are marginal. A hierarchical conspectus of the syntaxa is provided which includes the following nomenclaturally relevant new or validated names of various ranks (in alphabetic order): Alysso sphaciotici-Valantion apricae, Arenario fragillimae-Silenetum antri-jovis, Arenarion creticae, Astragalion cretici, Berberido creticae-Astragaletum cretici, Cicero incisi-Silenetum variegatae, Colchico cretensis-Cirsion morinifolii, Fumano paphlagonicae-Helianthemetum hymettii, Gypsophilo nanae-Arenarietum creticae, Hyperico kelleri-Anchusetum cespitosae, Lomelosio sphacioticae-Centranthetum sieberi, Paronychio macrosepalae-Juniperetum oxycedri, Saturejo spinosae-Scutella-rietalia hirtae, Sideritido syriacae-Verbascetum spinosi, Verbascion spinosi

Les travertins de Saint-Antonin : squence gobotanique et climato-anthropique holocne (Bouches-du-Rhne, France), 2003, Guendon Jeanlouis, Ali Adam A. , Roiron Paul, Terral Jeanfrdric, Danna Andr, Diazdelolmo Fernando, Baenaescudero Rafael
Travertine deposit of St-Antonin (Bouches-du-Rhne, France): lithostratigraphy, palaeobotany and Holocene palaeoenvironments - Travertines are carbonate deposits formed generally during temperate climatic periods. The travertine of Saint-Antonin was formed during the Holocene in accordance with this model. They usually present a succession of travertinous units and detrital sedimentary levels containing, respectively, leaf impressions and charcoal; snail shells and archaeological material have also been preserved, essentially in detritial levels. Two kinds of plant remains (leaf imprints and charred wood) have been sampled and analysed, allowing the reconstruction of vegetation dynamics based on a well-defined sedimentary sequence. Our results were compared with those of previous malacalogical, archaeological studies and climatic changes. The Preboreal and Boreal sequence, characterised by travertine unites with detritial deposits, is dominated by a riverside vegetation (Populus alba, Salix sp., Phragmites communis) associated with some pubescent oak growing in the plateau. After this first period, detritial levels and hygrophilous species decrease. Correlatively travertinous facies and leaf impressions of mesophilous forest species increase (Quercus pubescent, Acer monspessulanum). They suggest the existence of homeostatic conditions, such as regular river flow, dense vegetation and few disturbances during deposition. The Middle Atlantic period shows optimal travertinisation and maintenance of forest environment. But this period is characterised by the beginning of the Quercus pubescens regression and the dominance of Acer monspessulanum. From the Atlantic to the first part of Subboreal, important detrital sedimentary levels disturb the deposition of carbonate. They contain reworked archaeological material dating to the Neolithic. Vegetation seems to have been profoundly affected by intensive human exploitation. This process has broken up the forested area into different plant communities and favoured the dominance of heliophilous and thermophilous species (Pinus halepensis, Rubus ulmifolius and Juniperus sp.).

Do woody plants affect streamflow on semiarid karst rangelands?, 2005, Wilcox B. P. , Owens M. K. , Knight R. W. , Lyons R. K. ,
There is considerable public and political pressure to reduce woody plant cover on rangelands as a means of increasing water yield, despite the lack of studies documenting that such a strategy is effective. In the Texas Hill Country, runoff from the Edwards Plateau recharges the highly productive and regionally vital Edwards Aquifer. The dominant woody plant on the Plateau is Ashe juniper (Juniperus ashei Buchholz). To understand how woody plant cover may affect the amount and timing of runoff in this region, we monitored streamflow from nine small (3- to 6-ha) watersheds over a 13-year period. After the first two years (initial observations), 100% of the shrub cover was removed from three of the watersheds and similar to70% from another three. Following these treatments we continued to monitor runoff for four years, suspended monitoring for four and a half years, and then resumed monitoring for an additional three years. Runoff from these nine first-order watersheds generally accounted for <5% of the total precipitation and occurred entirely as stormflow (there was no baseflow before or after treatment). Some runoff was generated as subsurface flow, as indicated by hydrographs showing prolonged runoff (typically lasting hours longer than the rainfall). We evaluated the influence of woody plant cover on streamflow by comparing streamflow during the four-year treatment period with that during the posttreatment period (when considerable recovery of woody plants had taken place). Our findings indicate that changes in woody plant cover had little influence on the amount, timing, or magnitude of streamflow from these watersheds. On the basis of this work and other observations in the region, we hypothesize that, for small watersheds, changes in shrub cover will have little or no effect on streamflow except where springs are present

Discriminating Sources and Flowpaths of Anthropogenic Nitrogen Discharges to Florida Springs, Streams and Lakes, 2005, Bacchus St, Barile Pj,
Surface discharges of anthropogenic nutrients historically have been the focus of Florida's water-quality regulations. Groundwater contributions to eutrophication of Florida's surface waters are a more recent focus. Florida's naturally oligotrophic springs, streams, and lakes are experiencing significant anthropogenic nutrient contamination resulting from groundwater discharges with elevated nitrate. Sources of nitrate contamination to these surface-water ecosystems include sewage effluent, industrial animal waste (concentrated animal feedlot operations) and inorganic fertilizers. In this study, stable nitrogen isotope ({delta}15N) analysis of freshwater macrophytes was combined with basic knowledge of watershed and springshed land use and aquifer characteristics to provide evidence of nitrogen contamination sources and groundwater flowpaths. Selected naturally oligotrophic ecosystems included springs and a spring-run stream within the Ocala National Forest (ONF) and springs, a blackwater stream, and a sinkhole lake on or adjacent to state lands. Elevated {delta}15N values ([~] 8 to 12{per thousand}) in ONF macrophytes indicated nitrogen contamination from sewage effluent. Underground injections of effluent and other wastes at ONF's Alexander and Juniper Springs Recreation Areas are the sole source of contaminants flowing through the sandy, surficial aquifer at those study areas. Samples from springs on state lands indicated nitrogen contamination from various sources via regional groundwater flowpaths. At Lake Placid's state lands, a dairy-waste lagoon was the groundwater source of nitrogen contamination via the sandy, surficial aquifer. Bulow Creek {delta}15N macrophyte values ([~] 5 to 8{per thousand}) suggested contamination from both cattle and septic tank leachate. Results indicated that uptake of anthropogenic nitrogen occurred in invasive alien and nuisance native macrophytes in the four freshwater ecosystem types evaluated

Sinkholes and the Engineering and Environmental Impacts of Karst, 2005, Beck B. F.

Conference Proceedings

Sinkholes and the Engineering and Environmental Impacts of Karst Contains over 70 papers addressing karst topography which impacts water resources, waste disposal, foundation stability, and a multitude of other geotechnical and environmental issues. These papers were presented at the 10th Multidisciplinary Conference held September 24-28, 2005 in San Antonio, Texas and Sponsored by the Geo-Institute of ASCE, P. E. LaMoreaux & Associates, Inc. and Edwards Aquifer Authority. The goal of this conference was to share knowledge and experience among disciplines by emphasizing practical applications and case studies. This proceedings will benefit environmental and geotechnical engineers, and others involved in water resources, water disposal, and foundation stability issues.

Contents:

Application of Geophysical Logging Techniques for Multi-Channel Well Design and Installation in a Karst Aquifer (by Frank Bogle, ...)

Case Studies of Massive Flow Conduits in Karst Limestone (by Jim L. Lolcama)

A Case Study of the Samanalawewa Reservoir on the Walawe River in an Area of Karst in Sri Lanka (by K. Laksiri, ...)

Characterization and Water Balance of Internal Drainage Sinkholes (by Nico M. Hauwert, ...)

Characterization of Desert Karst Terrain in Kuwait and the Eastern Coastline of the Arabian Penninsula (by Waleed Abdullah, ...)

Characterization of a Sinkhole Prone Retention Pond Using Multiple Geophysical Surveys and Closely Spaced Borings (by Nick Hudyma, ...)

Combining Surface and Downhole Geophysical Methods to Identify Karst Conditions in North-Central Iowa (by J. E. Wedekind, ...)

Complexities of Flood Mapping in a Sinkhole Area (by C. Warren Campbell, P.E.)

Conceptualization and Simulation of the Edwards Aquifer, San Antonio Region, Texas (by R. J. Lindgren, ...)

Database Development and GIS Modeling to Develop a Karst Vulnerability Rating for I-66, Somerset to London, KY (by Michael A. Krokonko, ...)

Design and Construction of the Foundations for the Watauga Raw Water Intake Facility in Karstic Limestone near the City of Johnson City, TN (by Tony D. Canale, P.E., ...)

Detection of Three-Dimensional Voids in Karstic Ground (by Derek V. Morris, P.E., ...)

Development and Evolution of Epikarst in Mid-Continent US Carbonates (by Tony L. Cooley, P.E.)

Dye Tracing Sewage Lagoon Discharge in a Sandstone Karst, Askov, Minnesota (by Emmit Calvin Alexander, Jr., ...)

The Effectiveness of GPR in Sinkhole Investigations (by E. D. Zisman, P.E., ...)

Effects of Anthropogenic Modification of Karst Soil Texture on the Water Balance of ?Alta Murgia? (Apulia, Italy) (by F. Canora, ...)

Environmental Isotope Study on Recharge and Groundwater Residence Time in a covered Ordovician Carbonate Rock (by Zhiyuan Ma, ...)

Error and Technique in Fluorescent dye Tracing (by Chris Smart)

Essential Elements of Estimating Engineering Properties of Karst for Foundation Design (by Ramanuja Chari Kannan, P.E., Fellow, ASCE)

Estimating Grout Quantities for Residential Repairs in Central Florida Karst (by Larry D. Madrid, P.E., ...)

Evaluation of Groundwater Residence Time in a Karstic Aquifer Using Environmental Tracers: Roswell Artesian Basin, New Mexico (by Lewis Land)

Experience of Regional Karst Hazard and Risk Assessment in Russia (by A. L. Ragozin, ...)

Experimental Study of Physical Models for Sinkhole Collapses in Wuhan, China (by Mingtang Lei, ...)

Fractal Scaling of Secondary Porosity in Karstic Exposures of the Edwards Aquifer (by Robert E. Mace, ...)

The Geological Characteristics of Buried Karst and Its Impact on Foundations in Hong Kong, China (by Steve H. M. Chan, ...)

Geophysical Identification of Evaporite Dissolution Structures Beneath a Highway Alignment (by M. L. Rucker, ...)

Geotechnical Analysis in Karst: The Interaction between Engineers and Hydrogeologists (by R. C. Bachus, P.E.)

The Gray Fossil Site: A Spectacular Example in Tennessee of Ancient Regolith Occurrences in Carbonate Terranes, Valley and Ridge Subpovince, South Appalachians U.S.A. (by G. Michael Clark, ...)

Ground-Water Basin Catchment Delineation by Bye Tracing, Water Table Mapping, Cave Mapping, and Geophysical Techniques: Bowling Green Kentucky (by Nicholas C. Crawford)

Groundwater Flow in the Edwards Aquifer: Comparison of Groundwater Modeling and Dye Trace Results (by Brian A. Smith, ...)

Grouting Program to Stop Water Flow through Karstic Limestone: A Major Case History (by D. M. Maciolek)

Highway Widening in Karst (by M. Zia Islam, P.E., ...)

How Karst Features Affect Recharge? Implication for Estimating Recharge to the Edwards Aquifer (by Yun Huang, ...)

Hydrogeologic Investigation of Leakage through Sinkholes in the Bed of Lake Seminole to Springs Located Downstream from Jim Woodruff Dam (by Nicholas C. Crawford, ...)

The Hydrologic Function of the soil and Bedrock System at Upland Sinkholes in the Edwards Aquifer Recharge Zone of South-Central Texas (by A. L. Lindley)

An Integrated Geophysical Approach for a Karst Characterization of the Marshall Space Flight Center (by Lynn Yuhr, ...)

Integrated Geophysical Surveys Applied to Karstic Studies Over Transmission Lines in San Antonio, Texas (by Mustafa Saribudak, ...)

Judge Dillon and Karst: Limitations on Local Regulation of Karst Hazards (by Jesse J. Richardson, Jr.)

Karst Groundwater Resource and Advantages of its Utilization in the Shaanbei Energy Base in Shaanxi Province, China (by Yaoguo Wu, ...)

Karst Hydrogeology and the Nature of Reality Revisited: Philosophical Musings of a Less Frustrated Curmudgeon (by Emmit Calvin Alexander, Jr.)

Karst in Appalachia ? A Tangled Zone: Projects with Cave-Sized Voids and Sinkholes (by Clay Griffin, ...)

Karstic Features of Gachsaran Evaporites in the Region of Ramhormoz, Khuzestan Province, in Southwest Iran (by Arash Barjasteh)

Large Perennial Springs of Kentucky: Their Identification, Base Flow, Catchment, and Classification (by Joseph A. Ray, ...)

Large Plot Tracing of Subsurface Flow in the Edwards Aquifer Epikarst (by P. I. Taucer, ...)
Lithology as a Predictive Tool of Conduit Morphology and Hydrology in Environmental Impact Assessments (by George Veni)

Metadata Development for a Multi-State Karst Feature Database (by Yongli Gao, ...)

Micropiling in Karstic Rock: New CMFF Foundation Solution Applied at the Sanita Factory (by Marc Ballouz)

Modeling Barton Springs Segment of the Edwards Aquifer Using MODFLOW-DCM (by Alexander Y. Sun, ...)

Multi-Level Monitoring Well Completion Technologies and Their Applicability in Karst Dolomite (by Todd Kafka, ...)

National-Scale Risk Assessment of sinkhole Hazard in China (by Xiaozhen Jiang, ...)

New Applications of Differential Electrical Resistivity Tomography and Time Domain Reflectometry to Modeling Infiltration and Soil Moisture in Agricultural Sinkholes (by B. F. Schwartz, ...)

Non-Regulatory Approaches to Development on Karst (by Jesse J. Richardson, Jr., ...)

PA State Route 33 Over Bushkill Creek: Structure Failure and Replacement in an Active Sinkhole Environment (by Kerry W. Petrasic, P.E.)

Quantifying Recharge via Fractures in an Ashe Juniper Dominated Karst Landscape (by Lucas Gregory, ...)

Quantitative Groundwater Tracing and Effective Numerical Modeling in Karst: An Example from the Woodville Karst Plain of North Florida (by Todd R. Kincaid, ...)

Radial Groundwater Flow at Landfills in Karst (by J. E. Smith)

Residual Potential Mapping of Contaminant Transport Pathways in Karst Formations of Southern Texas (by D. Glaser, ...)

Resolving Sinkhole Issues: A State Government Perspective (by Sharon A. Hill)

Shallow Groundwater and DNAPL Movement within Slightly Dipping Limestone, Southwestern Kentucky (by Ralph O. Ewers, ...)

Sinkhole Case Study ? Is it or Isn?t it a Sinkhole? (by E. D. Zisman, P.E.)

Sinkhole Occurrence and Changes in Stream Morphology: An Example from the Lehigh Valley Pennsylvania (by William E. Kochanov)

Site Characterization and Geotechnical Roadway Design over Karst: Interstate 70, Frederick County, Maryland (by Walter G. Kutschke, P.E., ...)

Soil Stabilization of the Valley Creek Trunk Sewer Relief Tunnel (by Jeffrey J. Bean, P.E., ...)

Some New Approaches to Assessment of Collapse Risks in Covered Karsts (by Vladimir Tolmachev, ...)

Spectral Deconvolution and Quantification of Natural Organic Material and Fluorescent Tracer Dyes (by Scott C. Alexander)

Springshed Mapping in Support of Watershed Management (by Jeffrey A. Green, ...)

Sustainable Utilization of Karst Groundwater in Feicheng Basin, Shandong Province, China (by Yunfeng Li, ...)

Transport of Colloidal and Solute Tracers in Three Different Types of Alpine Karst Aquifers ? Examples from Southern Germany and Slovenia (by N. Göppert, ...)

Use of the Cone Penetration Test for Geotechnical Site Characterization in Clay-Mantled Karst (by T. C. Siegel, ...)

The Utility of Synthetic Aperture Radar (SAR) Interferometry in Monitoring Sinkhole Subsidence: Subsidence of the Devil?s Throat Sinkhole Area (Nevada, USA) (by Rana A. Al-Fares)

Void Evolution in Soluble Rocks Beneath Dams Under Limited Flow Condition (by Emmanuel S. Pepprah, ...)


Impacts of Juniper Vegetation and Karst Geology on Subsurface Flow Processes in the Edwards Plateau, Texas, 2006, Dasgupta S, Mohanty Bp, Kohne Jm,
Impacts of Ashe juniper (Juniperus ashei J. Buchholz) and karst geology on the regional water cycle in the Edwards plateau region of Texas are complex and not well understood. The objective of our study was to gain a comprehensive understanding of the subsurface flow processes occurring at a juniper woodland site on the Edwards Plateau near Honey Creek State Natural Area. A 2.3-m-deep, 7-m-long trench was excavated at the downslope end of a 7 by 14 m experimental plot, and time domain reflectometry (TDR) probes were installed at various locations within the trench face to measure volumetric water contents. A multi-port telescopic boom type rainfall simulator was used to provide artificial rainfall on the plot. Six rainfall simulations and two dye-tracer tests were conducted on the plot during a 7-mo period. Subsurface flow was visually inspected at various locations on the trench face during artificial rainfall experiments and water content was monitored near slow and fast flow regions using TDR probes. The total volume of subsurface flow was also recorded after each rainfall simulation event. Results demonstrated that subsurface flow occurred in a bimodal manner, consisting of preferential/macropore flow around juniper root channels and planar fractures in the limestone, and pseudo-matrix flow through the soil matrix (water flowing primarily through the intermediate layers and lenses of soil between the rock layers). Preferential/macropore flow at the trench face depended on imposed boundary conditions and was independent of antecedent moisture content in the soil matrix. Pseudo-matrix flow response time decreased with high rainfall. During large rainfall events (>200 mm), water exchange was observed between the fractures and soil matrix. No apparent water exchange occurred between fractures and the soil matrix during small rainfall events. The dye studies indicated that fractures and juniper root channels are primary pathways for preferential/macropore flow occurring within the plot

Monitoring the disappearance of a perennial ice deposit in Merrill Cave, 2007, Fuhrmann K.
Merrill Cave, part of a Pleistocene lava flow within Lava Beds National Monument, is the site of ice deposits that have fluctuated widely in volume between the Pleistocene and Holocene Epochs. Remnant mineral deposition from ice levels on the walls in the lower level of the cave provides insight into the depth of the ice during this time. The disappearance of a large perennial ice deposit in the lower level of the cave was tracked using historical photographs and modern photographic and ice-level monitoring techniques. A major change in airflow patterns and temperatures in an as yet unexplored lower level of the cave are suspected to have initiated the decline in ice levels. Measurements taken of the elevation of the surface of the ice deposit show a loss of over 1.25 m of ice in eight years. Surface and interior losses of ice from evaporation and/or sublimation have resulted in the near total loss of the large main perennial ice pond in the lower level of the cave. Photographs also document a drastic change in ice volume and levels during the same period of time. Several theories for the disappearance of ice have been suggested. One possible explanation for the loss of ice is related to a significant seismic event in the region in 1993 that may have caused rock fall in another, inaccessible section of the cave and precipitated the loss of ice in the accessible lower level. The dramatic loss of ice may also be the result of climate changes that, over time, indirectly influenced ice levels in Merrill Cave. Visitor impacts to the ice deposit after a large cavity breached the surface of the deposit contributed to the decline of ice conditions. Lastly, the presence of western juniper (Juniperus occidentalis) in the terrestrial environment above the cave may influence the hydrology of the cave environment.

New insights into the carbon isotope composition of speleothem calcite: An assessment from surface to subsurface, 2012, Meyer, Kyle William

The purpose of this study was to provide new insights into the interpretation of speleothem (cave calcite deposit) δ13C values. We studied two caves in central Texas, which have been actively monitored for over 12 years. We compared δ13C values of soil CO2 (δ13Cs), cave drip water (δ13CDIC), and modern cave calcite (δ13Ccc). Measured average δ13C values of soil CO2 were -13.9 ± 1.4‰ under mixed, shallowly-rooted C3-C4 grasses and were -18.3 ± 0.7‰ under deeply-rooted ashe juniper trees (C3). The δ13CDIC value of minimally-degassed drip water in Natural Bridge Caverns was -10.7 ± 0.3‰. The carbon isotope composition of CO2 in equilibrium with this measured drip water is -18.1 ± 0.3‰. The agreement between juniper soil CO2 and drip water (within ~0.2‰) suggests that the δ13C value of drip water (δ13CDIC) that initially enters the cave is controlled by deeply-rooted plants and may be minimally influenced by host-rock dissolution and/or prior calcite precipitation (PCP). At Inner Space Caverns, δ13CDIC values varied with vegetation above the drip site, distance from the cave entrance, and distance along in-cave flow paths. Whereas CO2 derived from deeply-rooted plants defines the baseline for drip water δ13CDIC entering the caves, kinetic effects associated with the degassing of CO2 and simultaneous precipitation of calcite account for seasonal variability in δ13CDIC and δ13Ccc. We documented increases in δ13CDIC at a rate of up to 0.47‰/hour during the season of peak degassing (winter), suggesting that δ13CDIC variations may be controlled by total elapsed time of CO2 degassing from drip water (Ttotal). We also observed seasonal shifts in the δ13C values of modern calcite grown on glass substrates that are correlated with shifts in drip water δ13CDIC values and drip-rate. Therefore, we suggest that increased aridity at the surface above a given cave results in, slower drip-rates, higher Ttotal, and therefore higher δ13CDIC values. We propose that large variability (>2‰) in speleothem δ13Ccc values dominantly reflect major vegetation changes, and/or increasing Ttotal by slowing drip-rates. Based on these findings, variability in speleothem carbon isotope records may serve as a proxy for paleoaridity and/or paleovegetation change.


New insights into the carbon isotope composition of speleothem calcite : an assessment from surface to subsurface, 2012, Meyer, Kyle William

The purpose of this study was to provide new insights into the interpretation of speleothem (cave calcite deposit) δ13C values. We studied two caves in central Texas, which have been actively monitored for over 12 years. We compared δ13C values of soil CO2 (δ13Cs), cave drip water (δ13CDIC), and modern cave calcite (δ13Ccc). Measured average δ13C values of soil CO2 were -13.9 ± 1.4‰ under mixed, shallowly-rooted C3-C4 grasses and were -18.3 ± 0.7‰ under deeply-rooted ashe juniper trees (C3). The δ13CDIC value of minimally-degassed drip water in Natural Bridge Caverns was -10.7 ± 0.3‰. The carbon isotope composition of CO2 in equilibrium with this measured drip water is -18.1 ± 0.3‰. The agreement between juniper soil CO2 and drip water (within ~0.2‰) suggests that the δ13C value of drip water (δ13CDIC) that initially enters the cave is controlled by deeply-rooted plants and may be minimally influenced by host-rock dissolution and/or prior calcite precipitation (PCP). At Inner Space Caverns, δ13CDIC values varied with vegetation above the drip site, distance from the cave entrance, and distance along in-cave flow paths. Whereas CO2 derived from deeply-rooted plants defines the baseline for drip water δ13CDIC entering the caves, kinetic effects associated with the degassing of CO2 and simultaneous precipitation of calcite account for seasonal variability in δ13CDIC and δ13Ccc. We documented increases in δ13CDIC at a rate of up to 0.47‰/hour during the season of peak degassing (winter), suggesting that δ13CDIC variations may be controlled by total elapsed time of CO2 degassing from drip water (Ttotal). We also observed seasonal shifts in the δ13C values of modern calcite grown on glass substrates that are correlated with shifts in drip water δ13CDIC values and drip-rate. Therefore, we suggest that increased aridity at the surface above a given cave results in, slower drip-rates, higher Ttotal, and therefore higher δ13CDIC values. We propose that large variability (>2‰) in speleothem δ13Ccc values dominantly reflect major vegetation changes, and/or increasing Ttotal by slowing drip-rates. Based on these findings, variability in speleothem carbon isotope records may serve as a proxy for paleoaridity and/or paleovegetation change.


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