Results 81 to 90 of about 29,661 (201)

Zircon ages in granulite facies rocks: decoupling from geochemistry above 850 °C? [PDF]

open access: yes, 2018
Granulite facies rocks frequently show a large spread in their zircon ages, the interpretation of which raises questions: Has the isotopic system been disturbed? By what process(es) and conditions did the alteration occur?
A Boriani   +120 more
core   +1 more source

Late Paleozoic oxygenation of marine environments supported by dolomite U-Pb dating

open access: yesNature Communications
Understanding causal relationships between evolution and ocean oxygenation hinges on reliable reconstructions of marine oxygen levels, typically from redox-sensitive geochemical proxies.
Michal Ben-Israel   +5 more
doaj   +1 more source

Rapid Exhumation of Earth's Youngest Exposed Granites Driven by Subduction of an Oceanic Arc

open access: yesGeophysical Research Letters, 2019
Exhumation of plutonic systems is driven by a range of mechanisms including isostatic, tectonic, and erosional processes. Variable rates of plutonic exhumation in active subduction systems may be driven by idiosyncrasies of regional geology or by first ...
C. J. Spencer   +7 more
doaj   +1 more source

U–Th whole rock data and high spatial resolution U–Th disequilibrium and U–Pb zircon ages of Mt. Erciyes and Mt. Hasan Quaternary stratovolcanic complexes (Central Anatolia)

open access: yesData in Brief, 2020
Thirty-eight lava and pyroclastic samples were collected from Mt. Erciyes and Mt. Hasan, the two largest stratovolcanic complexes of the Central Anatolian Volcanic Province in Turkey.
Bjarne Friedrichs   +3 more
doaj   +1 more source

Zircon dissolution in a ductile shear zone, Monte Rosa granite gneiss, northern Italy [PDF]

open access: yes, 2008
The sizes, distributions and shapes of zircon grains within variably deformed granite gneiss from the western Alps have been studied. Zircon shows numerous indicators of a metamorphic response in both the host gneiss and a 5 cm wide continuous ductile ...
Dal Piaz   +14 more
core   +1 more source

Detrital zircon geochronology of Neoproterozoic to Middle Cambrian miogeoclinal and platformal strata: Northwest Sonora, Mexico [PDF]

open access: yesGeofísica Internacional, 2000
Eighty-five detrital zircon grains from Mesoproterozoic and/or Neoproterozoic to Middle Cambrian sedimentary strata in northwest Sonora, Mexico, have been analyzed to determine source terranes and provide limiting depositional ages of the units.
George E. Gehrels   +2 more
doaj  

U-Pb chronology of the Solar System's oldest solids with variable 238 U/ 235 U

open access: yes, 2016
Accurate determination of the absolute ages of the oldest Solar System objects - chondrules and Ca-Al-rich inclusions (CAIs), requires knowledge of their 238U/235U ratios.
Amelin, Yuri   +6 more
core   +1 more source

Shoshonitic enclaves in the high Sr/Y Nyemo pluton, southern Tibet: Implications for Oligocene magma mixing and the onset of extension of the southern Lhasa terrane [PDF]

open access: yes, 2020
Post-collisional potassic and high Sr/Y magmatism in the Lhasa terrane provides critical constraints on the timing and mechanism of subduction of Indian lithosphere and its role in the uplift of the Tibetan Plateau.
Asimow, Paul D.   +8 more
core  

Extensional faulting on Tinos island, Aegean sea, Greece: How many detachments? [PDF]

open access: yes, 2007
Zircon and apatite fission track (ZFT and AFT) and (U-Th)/He, 40Ar/39Ar hornblende, and U-Pb zircon ages from the granites of Tinos Island in the Aegean Sea, Greece, suggest, together with published ZFT data, that there are three extensional detachments ...
Altherr   +79 more
core   +3 more sources

Contributions of U-Th-Pb dating on the diagenesis and sediment sources of the Lower Group (BI) of the Mbuji-Mayi Supergroup (Democratic Republic of Congo) [PDF]

open access: yes, 2017
In this paper, we present new age constraints for the lower part of the Meso-Neoproterozoic sedimentary Mbuji-Mayi Supergroup (Democratic Republic of Congo, DRC).
Baudet, Daniel   +6 more
core   +2 more sources

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