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Showing 1 to 20 of 29 for “"Speleothems"”.
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Investigating Mexican paleoclimate with precisely dated speleothems
Speleothems, or sedimentary rocks formed in caves, act as valuable archives of past climate change due to their suitability for U-series dating and high-resolution proxy analysis. These records can provide insights into water availability and controls on hydrology prior to the instrumental record. …
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Investigating Mexican paleoclimate with precisely dated speleothems
Speleothems, or sedimentary rocks formed in caves, act as valuable archives of past climate change due to their suitability for U-series dating and high-resolution proxy analysis. These records can provide insights into water availability and controls on hydrology prior to the instrumental record. …
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Rates of natural climate change : a study of speleothems
Speleothems (cave calcite) provide many different proxy indicators for palaeoclimatic changes during the Quaternary era. Generally, the occurrence of growing speleothems is a strong proxy for global palaeoclimate, both geographically and through time. A database of speleothem U-Th ages shows some …
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Interpretations of Paleoclimate and Speleogenesis from Speleothems in Donnehue's Cave, Indiana
… conditions are cave deposits, especially speleothems (stalagmites and flowstones). A major obstacle in the overall understanding of continental climatic fluctuations in the Midwest is the scarcity of the well-dated paleoclimate records. This investigation provides additional data from the …
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GEOCHEMISTRY AND PETROGRAPHY OF SPELEOTHEMS FROM TURKEY AND IRAN: PALAEOCLIMATE AND DIAGENESIS
Abstract Speleothems contain key archives of palaeoclimatic information, which can be interpreted through multiple geochemical and petrographic proxies, and precisely dated by Uranium Series dating. As U/Th dating is only viable for samples up to approximately 700 kyr of age, U/Pb dating must be …
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Organic complexation in karst cave systems: implications for transition metal incorporation into speleothems
… record, secondary cave carbonate deposits, or speleothems, have proven to present particularly valuable archives of numerous environmental processes over a range of temporal and spatial scales. In this context, trace elements included in speleothems are increasingly used to bolster …
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Deep-lake carbonates and speleothems as high-resolution archives of paleohydrology in the Bonneville Basin, UT
… records Mg/Ca ratios and [delta]13C values of speleothems from Lehman Caves, NV, located on the western edge of the Bonneville Basin. These records suggest that the onset of mid- Holocene drying in the Great Basin was at 8.2 ka, coincident with the collapse of the Laurentide Ice Sheet.
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Physical and geochemical response in cave drip waters to recent drought, central Texas, USA : implications for drought reconstruction using speleothems
… a given cave may allow for the identification of speleothems that are most likely to be geochemically responsive to changes in climate, making the speleothem sampling process more informed and less destructive.
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Speleothem climate capture of the Neanderthal demise
… was to construct a palaeoclimate record using speleothems from Matienzo, northern Iberia, across the period encapsulating the Neanderthal demise. Contemporary cave monitoring of Cueva de las Perlas has demonstrated the potential for speleothems to be used as indicators of past climate and …
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Cave air and dripwater variability in Cathedral Caverns, Alabama
… influencing deposition and δ18O chemistry of speleothems within the cave. Cave dripwater (δ18O and δD) isotope values for the Southeast, US are thought to be consistent with a yearly average. Cave monitoring of Cathedral Caverns, however, indicates that dripwater values are biased towards the …
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CHARACTERIZATION OF THE NORTHERN HEMISPHERE GLACIAL CYCLE-II AND TERMINATION FROM HIGH RESOLUTION SPELEOTHEM ISOTOPE AND TRACE ELEMENTAL TIME-SERIES DATA, SOUTHWEST UNITED STATES
Absolute dated high-resolution records from two speleothems from the southwestern United States (SW USA) are used to constrain the timing and character of the Penultimate Glacial period (NH Glacial-II) and the following glacial termination (T-II) in the northern hemisphere (NH). Speleothems FS-TR3 …
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An examination of trace element concentrations across calcite/aragonite transitions in a Madagascan stalagmite
Calcite and aragonite speleothems have been used for the past few decades to provide paleoclimate information, but in speleothems of mixed mineralogy the signal of mineral changes can complicate understanding of climate signals also present. This mineral signal must therefore be examined and …
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Paleoclimate reconstructions over the last century from a tropical speleothem on Niue Island, South Pacific
The study examines the question whether speleothems from Niue Island (19°00'S, 169°50'W), a large carbonate platform located at the edge of West Pacific Warm Pool, can serve as archives of hydroclimate controlled by El-Niño/Southern Oscillation (ENSO) and of catastrophic cyclones that frequent the …
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Recent extreme events in a tropical stalagmite: Multi-proxy records and analysis of ecosystem delta carbon-13 value sensitivity to weak climate forcing
<p>Speleothems are emerging as important and detailed chronological records of environmental change. Integrating exploration of modern speleothem records of environmental variability, related forcing factors, and understanding and suggests new potential proxies. This dissertation demonstrates the …
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The terrestrial carbon cycle in transition: tracking changes using novel tracers on multiple timescales
… Zealand’s palaeo-environmental archives (e.g. speleothems and lake sediments) provide a unique opportunity to reconstruct the concentrations and characteristics of DOC under changing climate conditions over centennial/millennial timescales. New Zealand was uninhabited by humans until the 13th …
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Estudo geomorfológico em ambiente subterrâneo: gruta do Lobo Guará, município de Santa Rita, Paraíba.
… of cement and lime in it the presence of speleothems is almost nil, and its flora and fauna prove to be quite fragile, and these highly adapted to the site. Thus, it is concluded that despite being the first exploratory study in the cavity, it is important to emphasize that conducting …
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A 20,000 year flowstone record of Gulf of Mexico sourced moisture in Texas
… GoM moisture source since the LGM and that speleothems in the region might record this signal. Furthermore, this study developed a novel workflow that could be applied to other flowstone samples, which would allow for greater spatial coverage of speleothem-based paleoclimate reconstructions …
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Geochemistry of cave pools in the Guadalupe Mountains, NM : implications for geomicrobiology
… and presence of biothems (biogenically mediated speleothems, including pool fingers). Infiltrating waters dominant the character of the cave pool waters. Variations in geochemistry of the cave pools can be explained by several geochemical processes: 1) infiltrating water-rock interactions 2) …
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