Results 101 to 110 of about 153,773 (348)
Vertical profiling of shock attenuation at the Rochechouart impact structure, France
Abstract Rochechouart, south‐west France, is a complex impact structure. Here, we present the first report of shock barometry of quartz from what are likely parautochthonous basement units at depth, based on samples from the 2017 C.I.R.I.R drilling campaign. The crystallographic orientations of 725 sets of PDFs in 512 quartz grains in samples from four
P. Struzynska +4 more
wiley +1 more source
U-Pb dating by LA ICP-MS is one of the most popular and successful isotopic techniques available to the Earth Sciences to constrain timing and rates of geological processes thanks to its high spatial resolution, good precision (absolute U/Pb age ...
Laura Bracciali
doaj +1 more source
Anomalous supply of bioessential molybdenum in mid-Proterozoic surface environments [PDF]
We are grateful to A. Sandison and W. Thayalon for skilled technical support, and Mike Porter and an anonymous reviewer, who helped to clarify the manuscript.Peer ...
Lindgren, Paula, Parnell, John
core +1 more source
Abstract Libyan Desert Glass (LDG) is an ~29 million years old, silica‐rich glass found in Western Egypt. Whether this glass formed in an impact cratering context associated with the hypervelocity collision of a cometary/asteroidal body or radiative heating during an airburst is debated. Determination of the formation temperatures and pressures of rare
Niccolò Magnani +6 more
wiley +1 more source
Zircons and zircon’s geochronology of gabbro Nurali massif (the Southern Urals)
Object. In the article presents the the results of mineralogy, geochemistry and isotope-chronological investigation of zircons from gabbro Nurali massif. Materials and methods . Amphibole gabbro is the fine-grained and massive texture rock, which cosists
Artur A. Krasnobaev, Petr M. Valizer
doaj +1 more source
Ancient tin production: Slags from the Iron Age Carvalhelhos hillfort (NW Iberian Peninsula) [PDF]
Provenance and production of tin in the Ancient World has since long been a major topic of discussion among archaeologists. In Western Europe, where significant tin ore (cassiterite) deposits are known, only a few remains of ancient tin production, such ...
Figueiredo, Elin +5 more
core +1 more source
Sensitive High-Resolution Ion Microprobe (SHRIMP) U-Pb analyses of zircons from Paleoarchean (~3.4 Ga) tonalite-gneiss called the Older Metamorphic Tonalitic Gneiss (OMTG) from the Champua area of the Singhbhum Craton, India, reveal 4.24-4.03 Ga ...
T. Chaudhuri +4 more
semanticscholar +1 more source
Moon's volcanic history revealed in glassy spherules from Apollo 17 soil 76501
Abstract Rapidly quenched droplets of pyroclastically erupted lava are common in lunar regolith at landing sites proximal to the maria. Here, we document the U‐Pb chronologies, major element, and trace element compositions of picritic glassy particles from Apollo 17 regolith sample 76501. These particles are dominated by high‐Ti compositions similar to
Alexander A. Nemchin +9 more
wiley +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]
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
Abundance and Partitioning of OH in a High-pressure Magmatic System: Megacrysts from the Monastery Kimberlite, South Africa [PDF]
Concentrations of OH, and major and trace elements were determined in a suite of mantle-derived megacrysts that represent the crystallization products of a kimberlite-like magma at ~5 GPa and ~1400–1100°C.
Bell, David R. +2 more
core +1 more source

