Results 41 to 50 of about 2,698 (196)

Evaluating maturity of organic matter in hydrated C1 and CM‐like clasts and a dehydrated clast within a polymict eucrite and a howardite

Meteoritics &Planetary Science, EarlyView.
Abstract Volatile‐rich xenolithic clasts in different types of brecciated meteorites represent unique pristine solar system material. This study investigates the maturity and thermal history of organic matter using Raman spectroscopy and aqueous alteration effects using infrared spectroscopy in the matrix of 15 volatile‐rich clasts (C1 and CM‐like ...
Swarna Prava Das, Alessandro Maturilli, Aurélie Van den Neucker, Markus Patzek, Dipak Kumar Panda, Gopal K. Pradhan, Guneshwar Thangjam, Surya Snata Rout   +7 more
wiley   +1 more source

Initialer Magmatismus und seine Erzbildung in der Beleuchtung des Koli-Kaltimogebiets [PDF]

Bulletin of the Geological Society of Finland, 1969
In the Koli—Kaltimo area, North Karelia, Finland, the initial igneous activity of the Karelidic zone has produced diabase dikes and spilitic sills. Some of the sills have differentiated forming spilitic rock associations, which range from peridotite to ...
T. Piirainen
doaj   +1 more source

The Ames impact structure, Oklahoma: New radioisotopic constraints and implications for North American impact chronology

Meteoritics &Planetary Science, EarlyView.
Abstract The Ames impact structure (Oklahoma) is thought to have formed during the Ordovician Meteor Event, based on conodont biostratigraphy of its crater fill. Here, U–Pb zircon dates from its impact‐melt portion, conducted using secondary ion mass spectrometry and laser ablation–inductively coupled plasma–mass spectrometry (n = 37 spots), yield a ...
Elizabeth J. Catlos, Andrew F. Parisi, Michael E. Brookfield, Timmons Erickson, Sean P.S. Gulick, Axel K. Schmitt, Daniel F. Stockli, Daniel P. Miggins, Ben Ruchte, Mark Cloos   +9 more
wiley   +1 more source

Lithium Kolmozero deposit of rare metal pegmatites: New data on rare element composition (Kola Peninsula)

Литосфера, 2018
The article is devoted to studies the rare element composition of albite-spodumene pegmatites of the lithium with associated Be, Nb, Ta Kolmozero deposit.
Lyudmila N. Morozova
doaj   +1 more source

Origin and formation of a chondritic xenolith in Krymka (LL3.2, breccia): Indications for a late formation of the accretionary breccia

Meteoritics &Planetary Science, EarlyView.
Abstract An unusual chondritic xenolith was found in two sequentially prepared thin sections of a sample from the Krymka (LL3.2) chondrite. The xenolith has a rounded, slightly deformed shape of about 5 mm in apparent diameter and is partially surrounded by a double rim made of an inner fine‐grained silicate‐rich rim and an outer sulfide‐rich rim.
Aelita Girich, Addi Bischoff, Samuel Ebert, Kazuhide Nagashima, Andreas Morlok, Harald Hiesinger, Jasper Berndt   +6 more
wiley   +1 more source

Potassium isotopic compositions and exposure ages of evolved and silica‐rich achondrites

Meteoritics &Planetary Science, EarlyView.
Abstract Some of the oldest igneous rocks in the Solar System include evolved and silica‐rich achondrites that originate from parent bodies less than 1000 km in diameter, referred to as planetesimals. While Earth was initially in a molten state and required continental crust formation and plate tectonics to generate andesite bulk compositions, evolved ...
Z. Vaci, Z. Tian, P. Koefoed, M. Habermann, M. Humayun, K. Ziegler, H. Busemann, D. Krietsch, J. M. D. Day, K. Wang   +9 more
wiley   +1 more source

Nature, origin, and phosphorylation potential of the phosphorus/sulfur‐bearing nanoscale multiphasic assemblages in the CM chondrites Murchison and Murray

Meteoritics &Planetary Science, EarlyView.
Abstract Carbonaceous chondrites contain phosphorus, whose speciation and thus history remain to be investigated. Phosphorus/sulfur‐bearing assemblages have been reported in carbonaceous CM chondrites, but there is no consensus about their exact compositions and origins.
Valentine Megevand, Sylvain Bernard, Corentin Le Guillou, Roberto Conconi, François Guyot   +4 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

Meteoritics &Planetary Science, EarlyView.
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

Ionoluminiscencia de silicatos de utilización en cerámica a temperaturas criogenicas

Boletín de la Sociedad Española de Cerámica y Vidrio, 2004
Requirements on accurate physical properties need new characterization techniques for structural defects. The use of light ions such as H+ and He+ with MeV energies allows penetration to a depth of several microns in most materials producing strong ...
García-Guinea, J., Hole, D., Finch, A., Correcher, V., Valle-Fuentes, F. J., Can, N., Townsend, P. D.   +6 more
doaj  

Geophysical update of the diameter of the Zhamanshin impact structure, Kazakhstan

Meteoritics &Planetary Science, EarlyView.
Abstract The rim of the 0.9‐Ma‐old Zhamanshin impact crater in Kazakhstan is considered to be almost completely exposed via a series of hills surrounding a central flat area, indicating an apparent diameter of 14 km. This would make Zhamanshin the second largest impact crater of the Quaternary period. However, the overall geometry of these hills is not
Yoann Quesnel, Dilyara M. Kuzina, Jérôme Gattacceca, Minoru Uehara, Ayrat G. Kharisov, Dmitry D. Badyukov, Pierre Rochette   +6 more
wiley   +1 more source