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Showing 1 to 20 of 91 for “"87Sr/86Sr"”.
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Examining the diagnostic value of 87SR/86SR for midwestern blue-gray chert source determination
Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2023-12-04 without embargo terms
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Investigation of Aztec Wash pluton using 87sr/86sr as a tool to understand mushzone differentiation
Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2023-09-01 without embargo terms
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A background investigation into the feasibility of heavy stable isotopes (87Sr/86Sr) as source tracers of early hominids
Heavy stable strontium isotope ratios (⁸⁷Sr/⁸⁶Sr) may be used to characterize the habitat choices of early hominids. The basis for this approach is that different geological substrata may have a characteristic range of ⁸⁷Sr/⁸⁶Sr ratios in the available soil strontium pool. This range may be …
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Crustal contamination recorded by zoned plagioclase in primitive Karoo flood basalts, Luenha River, Mozambique
… paljastivat näiden pikriittien 87Sr/86Sr suhteen vaihtelevan kondriittisesta radiogeeniseen, eNd arvot ovat lähes kondriittisia. Vaihtelevat 87Sr/86Sr suhteet voivat johtua kiteytymisen jälkeisestä muuttumisesta, kontaminaatiosta, magmojen sekoittumisesta tai lähteen …
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Geochemical Investigations of Mineral Weathering: Quantifying Weathering Intensity, Silicate versus Carbonate Contributions, and Soil-Plant Interactions
… on very different questions. Examination of the 87Sr/86Sr ratios of architectural ponderosa pine in Chaco Canyon, New Mexico confirms a societally complex style of timber procurement from the 10th to the 12th centuries. In El Malpais National Monument, New Mexico, we measured the 87Sr/86Sr ratios …
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Using Strontium Isotopes in Conjunction with Major, and Trace Elements to Identify Water/Rock Interaction in the Upper Kittitas County, Washington
… through water-rock interaction. A wide range of 87Sr/86Sr (0.7040 to 0.7068) in surface waters, springs, and groundwater from wells was found, allowing for identification of the individual signatures of lithologic units. Rock leachates from different lithology were compared to water samples to …
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Groundwater hydrogen, oxygen, and strontium isotope variation of Hout Bay Valley, Cape Town
… were analysed for strontium isotope composition (87Sr/86Sr) to determine the applicability of strontium to trace the source of groundwater. The 87Sr/86Sr ratios in Hout Bay groundwater vary from 0.710 to 0.731. There is a strong negative correlation between 87Sr/86Sr and δ18O (r = -0.91). The low …
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Petrologic Significance of Multiple Magmas in the Quottoon Igneous Complex, NW British Columbia and SE Alaska
… <750 ppm, avg. LaN/YbN = 10.4, and initial 87Sr/86Sr ratios that range from 0.70513 to 0.70717. The suite II rocks have Sr concentrations >750 ppm, avg. LaN/YbN = 23.1, and initial 87Sr/86Sr ratios that range from 0.70617 to 0.70686. This study proposes that the parental QIC magma (initial …
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An aqueous geochemical and hydrologic study of the springs and wells of the Sevilleta National Wildlife Refuge : evaluating hydrochemical pathways
… elements, Cl/Br ratios, δ18O, δD, δ13C, and 87Sr/86Sr ratios) and geochemical modeling along a series of transects within the Sevilleta National Wildlife Refuge. In the rift, several potential flow systems can be envisioned: 1) exogenic fluids in shallow unconfined aquifers with recent …
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Using high resolution Sr isotope data from the Nama Group, South Africa, to constrain global stratigraphic relationships and continental weathering rates in the terminal Ediacaran
… by diagenetic alteration. To ensure that the 87Sr/86Sr ratios generated in this study were reflective of primary seawater signals, a sequential leaching procedure, first proposed by Bailey et al., (2000), was tested on Ediacaran bulk rock carbonate samples. The successful implementation of the …
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Multi-isotope analysis and the reconstruction of prey species palaeomigrations and palaeoecology
… analysis of teeth and bone, including strontium (87Sr/86Sr), oxygen (d18O), carbon(d13C), nitrogen (d15N) and sulphur (d34S). Teeth (enamel and dentine) were sequentially-sampled in order to reconstruct time-series isotopic profiles at an intra- and inter-individual scale, allowing an assessment …
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Strontium isotope tracing of prehistoric human mobility in France
… explores the use of strontium isotope ratios (87Sr/86Sr) to trace prehistoric human mobility patterns. Strontium isotope ratios vary across the landscape based on the age and composition of the underlying geology. Through diet humans incorporate strontium into their skeletal tissues such as …
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Strontium isotope tracing of prehistoric human mobility in France
… explores the use of strontium isotope ratios (87Sr/86Sr) to trace prehistoric human mobility patterns. Strontium isotope ratios vary across the landscape based on the age and composition of the underlying geology. Through diet humans incorporate strontium into their skeletal tissues such as …
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Geochemical Analysis of Mississippian Cherts and Devonian-Mississippian Novaculites, Southern Midcontinent Region
… source. Sr isotope ratios of the Boone samples (87Sr/86Sr ~ 0.7089) largely reflect Mississippian seawater Sr (87Sr/86Sr ~ 0.7080), while the novaculite samples contain more radiogenic Sr (87Sr/86Sr ~ 0.7121), likely reflecting Sr exchange from the detrital component within the Arkansas …
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Isotopic characterization of bedrock, sediments, and minerals as provenance tools: Examples from an inselberg in the Mojave Desert of SE California
… potential fingerprint for detrital provenance. 87Sr/86Sr ratios and (U-Th)/He ages are two independent isotopic signatures. The first provides the diagnostic magmatic signature, while the second provides a low temperature thermochronometer, which describes the exhumation or cooling history of …
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Diagenetic controls on porosity, thermal history, and hydrocarbons in the Wolfcamp A, eastern Midland Basin, Texas
… and SEM-EDS microscopy, as well as δ18O, δ13C, 87Sr/86Sr, and fluid inclusion analyses were performed. The diagenetic history could be divided into stages: Early Stage occurred near the sediment-water interface; Burial Stage occurred during burial and before tectonic fracturing; and Fracturing …
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The Development of Chemical and Biological Profiling for the Forensic Provenancing of Norfolk Soils
… have been carried out on a single source sample. 87Sr/86Sr ratios have been measured using MC-ICP-MS, and trace element concentrations measured using ICP-MS. The 87Sr/86Sr ratios are significantly different at each of the sample locations; although there is some variation in the replicates …
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The timing, composition, and source of subsurface diagenetic waters responsible for sulfide and carbonate mineralization in solution cavities of the ordovician galena group limestone, North Aurora, Illinois, USA
… in conjunction with changes in isotopic (87Sr/86Sr) and elemental concentrations (Ca, Na, Sr, Fe, Mg, and Mn) in calcite growth zones, suggest changes in the fluid chemistry and the source of the subsurface diagenetic waters that were responsible for dissolution and mineralization. The …
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Geochemical records in travertine veins at the Green River CO2 seeps (Utah)
… fluids they form from: trace metals, δ234Ui and 87Sr/86Sr. Laser ablation methods were developed to analyse these samples, allowing for rapid, high spatial resolution analysis. Accurate and precise show external reproducibility of ±42 x10-6 (2σ) for 87Sr/86Sr, 7 x10-7 (2σ) for 230Th/238U and ±1.3 …
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Origin of geochemical heterogeneity in the mantle : constraints from volcanism associated with Hawaiian and Kerguelen mantle plumes
… a depleted component (i.e., relatively low 87Sr/86Sr with high 143Nd/144Nd and 176Hf/177Hf), probably related to Southeast Indian Ocean mid-ocean ridge basalt, but possibly intrinsic to the Kerguelen plume, and an enriched Kerguelen plume component. From -34 Ma to <1 Ma, on average the …
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