Results 111 to 120 of about 4,976,259 (186)

Dolomitic Microfossil Preservation in a Cryogenian Microbial Reef, Arkaroola (South Australia)

Geobiology, Volume 24, Issue 5, September/October 2026.
ABSTRACT Microbial dolostones that now form the Arkaroola reef, northern Adelaide Rift Complex, and were deposited during the Cryogenian interglacial period, display a wide range of meso‐scale stromatolite morphotypes in outcrop. Microcharacterisation involving optical microscopy, combined scanning electron microscopy and energy dispersive spectroscopy
France Champenois, Maree L. Corkeron, Annette D. George   +2 more
wiley   +1 more source

Uranium Isotope Evidence for Persistent Global Ocean Anoxia Across the Ediacaran–Cambrian Transition in Siberia

Geobiology, Volume 24, Issue 5, September/October 2026.
ABSTRACT The enigmatic Ediacara biota represents Earth's earliest example of macroscopic, complex life, yet the driving forces promoting their mid‐Ediacaran evolution and subsequent extinction across the Ediacaran–Cambrian boundary remain speculative. If these were true animals requiring oxygen for aerobic respiration, their rise has often been linked ...
Andrew D. Doerrler, Tian Gan, Geoffrey J. Gilleaudeau, Matthew G. Pedersen, Natalia Bykova, Vasiliy Marusin, Natalia A. Ivanova, Boris Kochnev, Dimitriy V. Grazhdankin, Karel Kletetschka, Alan J. Kaufman   +10 more
wiley   +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, 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, 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, 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

Journal 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, Bruno V. Ribeiro, Gavril Săbău, Fabricio Caxito, Paulo A. de Paiva‐Silva, Pierre Lanari, George Luvizotto, Mahyra Tedeschi   +7 more
wiley   +1 more source

LA-ICP-MS protocols for U-Pb geochronology and trace element analysis of zircons: Optimized implementation at the PetroChron laboratory. [PDF]

MethodsX
Pârlea M, Ene V, Ducea M, Luffi P, Stremțan C.   +4 more
europepmc   +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

Meteoritics &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, Jeongmin Kim, Sei‐Sun Hong   +2 more
wiley   +1 more source

Tectono-paleogeographic evolution of the Northern Margin of the North China Block based on provenance analysis of Jurassic strata in Liaodong Peninsula. [PDF]

Sci Rep
Xu J, Gao B, Pu C.
europepmc   +1 more source

Direct Detection of Hydrogen Reveals a New Macroscopic Crustal Water Reservoir on Early Mars

Geophysical Research Letters, Volume 53, Issue 16, 28 August 2026.
Abstract The next great leap in Martian exploration is the return of samples to Earth. Maximizing their scientific value requires non‐destructive analytical techniques for early three‐dimensional characterization. Neutron computed tomography (CT), highly sensitive to hydrogen, complements conventional X‐ray CT and enables the detection of hydrous ...
Estrid Buhl Naver, Katrine Wulff Nikolajsen, Martin Sæbye Carøe, Domenico Battaglia, Jens Frydenvang, Martin Bizzarro, Jakob Sauer Jørgensen, Kim Lefmann, Anders Kaestner, David Christian Mannes, Phil Cook, Henrik Birkedal, Thorbjørn Erik Køppen Christensen, Innokenty Kantor, Henning Friis Poulsen, Luise Theil Kuhn   +15 more
wiley   +1 more source

U-Pb dating of volcaniclastic deposits from the Sinj Basin: implications for provenance and the tectono-sedimentary evolution of the External Dinarides. [PDF]

Int J Earth Sci
Šamarija R, Andrić-Tomašević N, Mandic O, Zeh A, Mužek K, Pavelić D, Schwotzer M.   +6 more
europepmc   +1 more source