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Showing 1 to 16 of 16 for “"stable oxygen isotope"”.
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Stable oxygen isotope variability in seawater: Insights into past and present ocean circulation and hydroclimate
Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2025-02-04 without embargo terms
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Water balance and productivity of a Mediterranean oak woodland : Quantifying understory vegetation impacts by development of a stable oxygen isotope partitioning approach
… technique were combined with a novel stable oxygen isotope partitioning approach. Stable oxygen isotopes are valuable tracers for water movements within the ecosystem, but due to methodological restrictions in the past, it was necessary to validate modeling approaches and derive field …
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A late quaternary history of Agulhas-Benguela interactions from two sediment cores on the western continental slope of South Africa
… River continental slopes of South Africa. The stable oxygen isotope record of the benthic foraminifer, Cibicidoides wuellerstorfi, and the planktonic taxon, Globorotalia inflata, provide the stratigraphic framework from which the age models were created. The results indicate that biotic …
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Development and application of the mollusc Arctica islandica as a paleoceanographic tool for the North Atlantic ocean
… reflects the ambient temperature in its stable oxygen isotope (δ180) composition. However, the stable carbon isotope (δ13C) composition of the A. islandica shell likely is not a good recorder of ambient DIC δl3C, and likely responds to physiological controls. Four Δ14C time histories are …
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Paleoenvironmental Reconstruction of the Late Cretaceous Eastern Gulf Coastal Plain in Georgia and Alabama
… considerably warmer than modern terrestrial MAT. Stable oxygen isotope data from molluscan carbonate indicate mean sea surface temperature (SST) of 26.8 °C for the Santonian, 23.5°C for the early Campanian, and 28.8°C for the late Campanian. These paleotemperature compare with the modern Gulf …
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Advances in the reconstruction of temperature history, physiology and paleoenvironmental change : evidence from light stable isotope chemistry
The rationale of this study is to apply light stable isotope chemistry towards investigations that require temporally high-resolution data. High-resolution (or high sampling frequency) data sets, are critical for testing environmental and/or paleoenvironmental hypotheses that seek to explain …
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Evaluating the efficacy of Tridacna derasa and Hippopus hippopus for measuring ENSO signatures in Palau
… (SST) and salinity through variations in oxygen isotopes (δ18O). Their potential for reconstructing past climate variability makes them a critical tool for understanding El Niño Southern Oscillation (ENSO), the primary source of interannual climate variability on Earth. In this study, we …
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Lake Sediment-Based Reconstructions of Late-Holocene Lowland Environments of Dominican Republic and Barbuda, Northern Caribbean
… we interpreted, from sediment lithology and stable oxygen isotope data, at least ten storm events over the past 1,000 years, producing the first long record of storm activity from the island. During the Little Ice Age (1400−1800 CE), we interpreted an increased frequency of hurricane …
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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
… a weekly-monthly record of stalagmite stable isotope ratios showed low stable oxygen isotope excursions that corresponded to the historical record of tropical storm strikes in the region. Furthermore, excursion amplitude was related to the maximum intensity of storms prior to landfall. …
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Clams and climate: implications for measuring seasonality in the marine bivalve, saxidomus gigantea
… in select species of bivalves may complement stable oxygen isotope analysis, together providing a more precise paleoclimate reconstruction. This research utilizes the growth of Saxidomus gigantea, abundant both on modern and ancient coastlines to provide information about the length of its …
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Coccoliths and oxygen isotope observations from the sediment surface of the southwest Indian Ocean
… resistant microfossils below this depth. Stable oxygen isotope ratios in a planktonic foraminifera and percent abundances of E. huxleyi reveal that apart from cores taken in the Agulhas Passage, most of the core-top samples are probably less than 85,000 yrs. BP. Lightest isotope ratios of …
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Neogene to quaternary foraminifera from the western margin of southern Africa
… to Pleistocene phosphatic sediments. Strontium isotope stratigraphy and planktic foraminifera biostratigraphy provide age control of the Namibian shelf sediments. The planktic indicator species Globoquadrina dehsicens and Globigerinoides bisphericus support strontium isotope stratigraphy results …
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Seasonal Influences on the Carbon-Water Relations in Ponderosa Pine Forests in the Northern Boundary of the North American Monsoon System
… of the spatial and temporal variability of the stable carbon and oxygen isotopes in the cellulose of subsections of the tree rings (e.g., earlywood and latewood) collected from a network of thirteen sites along a latitudinal gradient extending from southern Arizona and New Mexico, through …
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The Mechanism and Timescales of Soil Formation in the Hyper-arid Atacama Desert, Chile
… cap-delta 17O) was calibrated using the stable oxygen isotope measurements in nitrates from four deserts with different mean annual precipitation rates. The paleo-precipitation history for the formation of the 225-cm deep trench soil profile was then reconstructed based on the soil …
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Climate change, water stress and agriculture in the Indus Civilisation, 3000-1500 BC
… agricultural stress. These techniques are first, oxygen isotope analysis of faunal bones and teeth; and second, stable carbon isotope analysis of crop remains. The oxygen analyses provide detailed records of monsoon intensity at a local, human scale, while the carbon analyses provide an empirical …