Results 51 to 60 of about 4,118 (239)

Evidence of hydrological control of Sr behavior in stream water (Strengbach catchment, Vosges mountains, France) [PDF]

, 2002
Strontium and particularly 87Sr/86Sr ratios in stream water have often been used to calculate weathering rates in catchments. Nevertheless, in the literature, discharge variation effects on the geochemical behavior of Sr are often omitted or considered ...
Aubert, Dominique, Stille, Peter, Viville, Daniel, Probst, Anne   +3 more
core   +1 more source

Assessment and Correction of Non‐Linearity Effects for In Situ Rb‐Sr Geochronology Applied to High 87Rb/86Sr Mica

Geostandards and Geoanalytical Research, EarlyView.
Key Points Measurement of 86Sr at count rates < 1500 cps can result in statistical bias. Non‐linear signals in analogue detection mode (e.g., Rb) present a challenge for accurately dating high 87Rb/86Sr mica (> 1000). Accounting for these considerations, high 87Rb/86Sr mica are dated here with accuracies of ∼ 1%.
Duane C. Petts, William J. Davis, Simon E. Jackson, Jamie A. Cutts, Janina Czas, Alfredo Camacho   +5 more
wiley   +1 more source

Resolving Micrometre‐Scale Zircon Growth in Silicic Systems by 7 μm LA‐MC‐ICP‐MS U‐Pb Dating: Linking Petrology and Geochronology in Silicic Volcanic and Granitic Rocks from Victoria, Australia

Geostandards and Geoanalytical Research, EarlyView.
Key Points 7 μm spot‐diameter LA‐MC‐ICP‐MS analyses yield accurate zircon U‐Pb ages. 1013 Ω amplifier resistors improve low‐signal Pb measurements. Saturn correction protocols minimise down‐hole fractionation effects. We present a systematic evaluation of high spatial‐resolution zircon U‐Pb dating using a Thermo Scientific Neoma multi‐collector ICP‐MS ...
Cristiano Lana, John D. Clemens
wiley   +1 more source

Zooming into the Mediterranean outflow fossil moat during the 1.2–1.8 million years period (Early-Pleistocene): an approach by radiogenic and stable isotopes [PDF]

, 2015
The fossil Alvarez Cabral erosive Moat contains hemipelagite, contourite and turbidite facies where oceanography changes in the Mediterranean outflow are archived over the 1.2-1.8 Myr time period. Here we used Pb and Sr radiogenic isotopes to trace water
Antón López, Laura Ángela, Barrado, Ana Isabel, Fernández Díaz, Marta, Yllera de Llano, Abel, Reguera García, M. Isabel, Conde Vilda, Estefanía, Martín Lebreiro, Susana   +6 more
core   +1 more source

Thorium determination in seawater by inductively coupled plasma mass spectrometry: Method development and oceanographic applications

Talanta Open
Thorium isotopes in the ocean (including radiogenic isotopes and terrigenous-derived 232Th) serve as key tracers for studying land-derived material transport. While high-sensitivity and high-resolution inductively coupled plasma mass spectrometry (ICP-MS)
Yingjie Zou, Peng Wang, Lei Xu, Hong Ren, Yiyao Cao   +4 more
doaj   +1 more source

First isotope analysis and new radiocarbon dating of Trypillia (Tripolye) farmers from Verteba Cave, Bilche Zolote, Ukraine

Documenta Praehistorica, 2017
This paper presents an analysis of human and animal remains from Verteba cave, near Bilche Zolote, western Ukraine. This study was prompted by a paucity of direct dates on this material and the need to contextualise these remains in relation both to the
Malcolm C. Lillie, Chelsea E. Budd, Inna D. Potekhina, Douglas Price, Mykhailo Sokhatsky, Alexey G. Nikitin   +5 more
doaj   +1 more source

Subduction Initiation and Early Subduction Zone Development: Insights From the P–T–t Path of the Bay of Islands Metamorphic Sole

Journal of Metamorphic Geology, EarlyView.
ABSTRACT The processes involved during subduction initiation (SI) remain poorly constrained, in part due to the rarity of geological archives. Ophiolites and their underlying metamorphic soles are thought to form during subduction zone infancy and may thus provide critical constraints. Metamorphic soles are derived from oceanic crust of the lower plate
François Fournier‐Roy, Carl Guilmette, Mark Coleman, Kyle Larson, Douglas K. Tinkham, Alana M. Hinchey, John Wakabayashi, Jean H. Bédard, Louise Mérit, Philippe Agard, Loïc Labrousse, Antoine Godet   +11 more
wiley   +1 more source

Thermal histories of El Médano 300 (EM 300) and Northwest Africa 8155 (NWA 8155): Implications for the diversity of IAB‐ungrouped iron meteorites and their parent bodies

Meteoritics &Planetary Science, EarlyView.
Abstract This study provides the first petrographic, crystallographic, and chemical comparison between El Médano 300 (EM 300) and Northwest Africa 8155 (NWA 8155), two particular IAB‐ungrouped iron meteorites. Both contain exceptionally large graphite nodules and “flowers”, providing unique insights into carbon behavior in metallic melts and cooling ...
L. Perez, M. Roskosz, F. Danoix, L. Kern, V. Megevand, C. Brillatz, B. Devouard, J. Gattacceca, M. Gounelle   +8 more
wiley   +1 more source

Radiogenic Strontium‐ and Uranium‐Isotope Tracers of Water‐Rock Interactions and Hydrothermal Flow in the Upper Geyser Basin, Yellowstone Plateau Volcanic Field, USA

Geochemistry, Geophysics, Geosystems
Natural radiogenic isotopes (primarily 87Sr/86Sr) from hot springs in the Upper Geyser Basin of the Yellowstone Plateau volcanic field and associated rocks were used to evaluate groundwater flow patterns, water‐rock reactions, and the extent of mixing ...
James B. Paces, Shaul Hurwitz, Lauren N. Harrison, Jacob B. Lowenstern, R. Blaine McCleskey   +4 more
doaj   +1 more source

Radiogenic isotope investigation of the St‐Robert H5 fall [PDF]

Meteoritics & Planetary Science, 2004
Abstract— The St‐Robert H5 chondrite yields a mineral/whole‐rock Pb‐Pb age of 4565 ± 23 Ma (2σ) comparable to the accepted age of most chondrites. The regression of chondrule data give a similar age of 4566 ± 7 Ma (2σ). These results imply that no major perturbation affected the Pb‐Pb systematics of this meteorite's parent body within the first few ...
Poirier, André, Doucelance, Régis, Gariépy, Clément   +2 more
openaire   +2 more sources