Results 71 to 80 of about 37,639 (216)
Key Points A new magnetite reference material (PF21mt) is available for δ18O measurements by SIMS. Reproducibility of measurement results in two laboratories suggest orientation bias of ±2‰ (2s) at 20 keV. Repeatability improves to ±1‰ (2s) when using a 13 keV protocol, suggesting reduced orientation bias. In situ isotope ratio measurements provide the
Michelle Ulrich +4 more
wiley +1 more source
The \textit{Spitzer}/Infrared Spectrograph spectra of three spectroscopically anomalous galaxies (IRAS~F10398+1455, IRAS~F21013-0739 and SDSS~J0808+3948) are modeled in terms of a mixture of warm and cold silicate dust, and warm and cold carbon dust ...
Hao, Lei +3 more
core +1 more source
Abstract We report new results from a study of shock‐related features in the L6 ordinary chondrites Northwest Africa (NWA) 4672 and NWA 12841. Our observations confirm the occurrence of eight high‐pressure (HP) minerals in each meteorite, namely, ringwoodite, majorite, akimotoite, wadsleyite, albitic jadeite, lingunite, tuite, and xieite.
I. Baziotis +5 more
wiley +1 more source
The structure and petrology of the Cnoc nan Cuilean Intrusion, Loch Loyal Syenite Complex, NW Scotland [PDF]
In NW Scotland, several alkaline intrusive complexes of Silurian age intrude the Caledonian orogenic front. The most northerly is the Loch Loyal Syenite Complex, which is divided into three separate intrusions (Ben Loyal, Beinn Stumanadh and Cnoc nan ...
Goodenough, Kathryn M. +5 more
core +3 more sources
Small‐scale elemental abundance variations in Ryugu particles from touchdown 1
Abstract Ryugu materials closely resemble CI chondrites' mineralogical, chemical, and isotopic compositions; yet minor but resolvable differences in certain elemental abundances are evident. In this study, the bulk chemical compositions of eight individual Ryugu particles (1.5–4.3 mg) from the first touchdown site (TD1) were determined using triple ...
Karina López García +6 more
wiley +1 more source
This study presents the first detailed investigation of pyroxene zoning within polymetallic skarn zones of the Elazığ region. Skarns develop along contacts between plutonic rocks (diorite and granite) and carbonate rocks, forming two main zones ...
Necla Koprubasi +2 more
doaj +1 more source
Petrography and mineral chemistry of Northeast Africa 053—A remnant of Martian crystal mush
Abstract In Earth's igneous systems, crystal mushes, crystal‐rich frameworks permeated by silicate melt, represent a common and fundamental stage in the evolution of magma bodies. However, whether crystal mushes occur within Martian igneous systems and play a comparable role is unknown. Here, we present a comprehensive petrography and mineral chemistry
Xhonatan Shehaj +2 more
wiley +1 more source
Biotite composition constrains Tongling skarn Cu–Au mineralization, eastern China
Skarn Cu, Au deposits are most important deposit-type in the Tongling region, eastern China, where skarn Au deposits are closely associated with pyroxene monzodiorite, and skarn Cu deposits are genetically related to quartz monzodiorite and granodiorite.
Sujuan Zhou +7 more
doaj +1 more source
Diffusion kinetics of 3He in pyroxene and plagioclase and applications to cosmogenic exposure dating and paleothermometry in mafic rocks [PDF]
In this study, we investigate the diffusivity of cosmogenic 3He in a variety of plagioclase and pyroxene compositions, and its application to paleothermometry and exposure dating in these minerals, through stepwise degassing experiments. While cosmogenic
M. Bergelin +5 more
doaj +1 more source
Al-Mg systematics of hibonite-bearing Ca,Al-rich inclusions from Ningqiang [PDF]
Hibonite-bearing Ca,Al-rich inclusions (CAIs) usually occur in CM and CH chondrites and possess petrographic and isotopic characteristics distinctive from other typical CAIs.
Guan, Yunbin, Hsu, Weibiao, Wang, Ying
core

