Results 141 to 150 of about 51,804 (265)

Provenance Constraints on Early India–Asia Collision: Evidence From the Late Cretaceous–Early Cenozoic Sulaiman–Katawaz Basin Fill

open access: yesBasin Research, Volume 38, Issue 5, September‐October 2026.
Integrated detrital zircon U–Pb, Nd–Sr isotopes and thermochronology record western Indian‐margin provenance reorganisation. Late Cretaceous–Palaeocene sediment supply was Indian‐affinity; Asian‐affinity input appeared across the Palaeocene–Eocene transition (~56.5–54.7 Ma), suggesting India–Asia collision was underway, while mixed provenance persisted
Nowrad Ali   +8 more
wiley   +1 more source

Red to Green: A Lipid Biomarker Record of Tonian‐Ediacaran Algae in Siberia

open access: yesGeobiology, Volume 24, Issue 5, September/October 2026.
ABSTRACT Multiple lines of evidence point to a major diversification of Eukarya in the late Tonian period, ca. 800–720 Ma ago. Regular steranes, lipid biomarkers primarily sourced from eukaryotes, are first unambiguously reported from multiple sites. Here, we present lipid biomarker stratigraphic records from two drill‐cores from the Lena‐Anabar Basin ...
Adriana I. Rizzo   +7 more
wiley   +1 more source

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

open access: yesGeostandards and Geoanalytical Research, Volume 50, Issue 3, Page 601-624, September 2026.
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   +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

open access: yesGeostandards and Geoanalytical Research, Volume 50, Issue 3, Page 625-647, September 2026.
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

(Ultra)high‐Pressure Metamorphism in Sedimentary Versus Basaltic Rocks: Insights From a Variscan Mélange in the South Carpathians

open access: yesJournal of Metamorphic Geology, Volume 44, Issue 8, Page 585-610, September 2026.
ABSTRACT Reconstructing the pressure–temperature–time (P–T–t) evolution of (ultra)high‐pressure rocks is essential for constraining subduction and collisional dynamics. Subduction zones are often investigated using basic eclogites, whereas nonbasic high‐pressure rocks remain comparatively understudied, potentially hindering a comprehensive ...
Otavio S. G. Silva   +7 more
wiley   +1 more source

Characterization of coesite‐bearing impact melt glass from the Hapcheon crater, Korea: Trimodal phase architecture, shock metamorphism, and implications for 40Ar/39Ar geochronology

open access: yesMeteoritics &Planetary Science, Volume 61, Issue 9, Page 2233-2257, September 2026.
Abstract We present the first micrometer‐scale, phase‐resolved compositional characterization of impact melt glass from the Hapcheon crater (~1.4 km apparent diameter), the first confirmed impact structure on the Korean Peninsula, integrating EPMA‐WDS (5 μm spot), confocal Raman spectroscopy (<1 μm spot), XRD, and 40Ar/39Ar step‐heating geochronology ...
Jin‐Young Lee   +2 more
wiley   +1 more source

Zircon Internal Deformation and Its Effect on U-Pb Geochronology: A Case Study from the Himalayan High-Pressure Eclogites

open access: yes
Zircon, with a chemical formula of ZrSiO4, is a widely used mineral for determining the crystallization age of igneous rocks. It is also used to constrain the timing of metamorphic events from its overgrowth or recrystallized domains.
Hafiz U. Rehman
core   +1 more source

Conditions of formation of the Gubanov intrusion of rapakivi granites (Wiborg massif)

open access: yesЗаписки Горного института
The article is devoted to determining the P-T conditions and formation mechanisms of the Gubanov intrusion (Wiborg rapakivi granite massif) using a suite of petrographic and geochemical methods combined with thermodynamic modelling (rhyolite-MELTS ...
Alexey V. Berezin   +3 more
doaj  

A calcite reference material for LA‐ICP‐MS U‐Pb geochronology

open access: yes, 2017
N. Roberts   +5 more
semanticscholar   +1 more source

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