نتایج جستجو برای: zircon

تعداد نتایج: 3386  

2006
E. R. VANCE

Further lines of the anomalous optical absorption spectrum in low metamict zircon have been observed in the infra-red. Low-temperature polarization studies have enabled a clear distinction to be made between lines due to the anomalous spectrum and those due to the normal spectrum of U ~in zircon. Magnetic circular dichroism measurements showed, for the anomalous spectrum, only contributions due...

Journal: :Southern Spaces 2016

2017
William R. Guenthner Peter W. Reiners Henrik Drake Mikael Tillberg

Craton cores far from plate boundaries have traditionally been viewed as stable features that experience minimal vertical motion over 100–1000 Ma time scales. Here we show that the Fennoscandian Shield in southeastern Sweden experienced several episodes of burial and exhumation from ~1800 Ma to the present. Apatite, titanite, and zircon (U-Th)/He ages from surface samples and drill cores constr...

2017
AAron J. Lussier sergei rouvimov Peter C. Burns Antonio simonetti

The intense heat and pressure resulting from the detonation of the world’s first nuclear device in the New Mexico desert, July 16, 1945, severely altered the arkosic sand, producing the fused, glassy material referred to as Trinitite. The study of Trinitite is key to the development of nuclear forensic techniques that can provide crucial information about a nuclear event, such as device composi...

2000
Ming Zhang Ekhard K H Salje Gian Carlo Capitani Hugues Leroux Andrew M Clark Jochen Schlüter

Recrystallization and structural recovery in α-decay damage in zircon samples have been studied using Raman spectroscopy. Fifteen zircon samples with different degrees of radiation damage have been thermally annealed between 600 K and 1800 K for up to 28 days and 8 hours. The experimental results from this study reveal that recrystallization in the damaged zircon samples is a multi-stage proces...

2017
Björn Baresel François-Xavier d’Abzac Hugo Bucher Urs Schaltegger

Accurate and precise dating of individual volcanogenic beds that spread across multiple sedimentary successions is a powerful tool to untangle stratigraphic age contradictions, since these horizons are deposited synchronously. In this study, we show that combining apatite chemistry with zircon age, Th/U ratio, and Hf isotope composition leads to reliable lateral correlation of volcanic horizons...

Journal: :Journal of physics. Condensed matter : an Institute of Physics journal 2017
Alka B Garg D Errandonea P Rodríguez-Hernández A Muñoz

The high-pressure (HP) behaviour of scandium vanadate (ScVO4) is investigated under non-hydrostatic compression. The compound is studied by means of synchrotron-based powder x-ray diffraction (XRD) and optical-absorption techniques. The occurrence of a non-reversible phase transition is detected. The transition is from the zircon structure to the fergusonite-type structure and takes place aroun...

2010
E. Climent Pascual J. M. Gallardo R. Sáez Puche M. Castro N. Taira J. Romero de Paz L. C. Chapon

The scheelite form of the TbCrO4 oxide has been obtained by treating TbCrO4-zircon at 4 GPa and 823 K. X-ray and neutron diffraction data reveal that the high-pressure polymorph of TbCrO4 crystallizes with tetragonal symmetry space group I41 /a and lattice parameters a=5.036 74 10 Å and c=11.3734 4 Å. Although bisdisphenoids TbO8 and tetrahedra CrO4 are present in both scheelite and zircon poly...

2005
ENCARNACIÓN PUGA MARK FANNING MIGUEL NIETO

Eclogites formed during the Eo-alpine metamorphic event are common within the ophiolitic unit of the Mulhacén complex, which forms part of the Betic Cordillera in southeastern Spain. A detailed study with cathodoluminescence (CL) images of zircon from these eclogites has revealed three types of domains, confirmed by some differences in their REE patterns and ages. There are a) igneous domains, ...

2015
B. P. Kohn M. E. Wagner Tim M. Lutz T. M. Lutz

A total of 17 sphene and 45 zircon fission track ages (FTA) are reported from the Piedmont Province of Pennsylvania, Delaware, and Maryland, the Reading Prong of New Jersey, and the Newark Basin of Pennsylvania. With the exception of one sphene sample, FTA fall within a relatively restricted age range: sphene 190-217 Ma (average 199 Ma) and zircon 143-218 Ma (average 184 Ma). Near concordance o...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید