Introduction: Apatite is one of the minerals that is rarely utilized in U-Pb geochronology, compared to some other U-rich accessory phases. Relatively low U concentration, commonly high proportion of common Pb and low closure temperature of U-Pb system of apatite inhibit its application as geochronological tool when other minerals such as zircon are widely available. However, zircon appear to b...

Introduction: Highly refractory micro-minerals such as zircon, monazite and baddeleyite can survive and record intense shock metamorphism, and occasionally recrystallize to date impact events. Their microscale records have the potential to be used to deduce the timing and magnitude of large impacts in ex-situ solar system samples (i.e. meteorites, crystal clasts in breccias) provided we have a ...

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Meteoritic zircons are rare, but some are documented to occur in asteroidal meteorites, including those of the howardite–eucrite–diogenite (HED) achondrite clan (Rubin, A. [1997]. Meteorit. Planet. Sci. 32, 231– 247). The HEDs are widely considered to originate from the Asteroid 4 Vesta. Vesta and the other large main belt asteroids record an early bombardment history. To explore this record, w...

Zircons found in mantle-sourced kimberlite provide probes into the isotopic chemistry of the asthenosphere and subcontinental lithospheric mantle. However, little is known about the conditions of formation of these zircons. A suite of 88 zircons found in kimberlites from Africa, Siberia, Brazil, and the United States have been analyzed for their Ti concentration and selected zircons were analyz...

Benthic foraminifera are single-celled eukaryotes that make a protective organic, agglutinated or calcareous test. Some agglutinated, single-chambered taxa, including Psammophaga Arnold, 1982, retain mineral particles in their cytoplasm, but the selective mechanism of accumulation is not clear. Here, we report the ability of a foraminiferal species to select and accumulate zircons and other hea...

Zircon and monazite from three restitic enclaves and one host dacite have been dated by ion microprobe (SHRIMP), with the aim of characterising their Miocene history and defining the timing relationships between crustal melting and eruption in the high-K calc-alkaline volcanics of the Neogene Volcanic Province of SE Spain. The studied samples are from the volcanic edifices of El Joyazo (Cerro d...

In a recent paper, we used Li concentration profiles and U-Th ages to constrain the thermal conditions of magma storage. Wilson and co-authors argue that the data instead reflect control of Li behavior by charge balance during partitioning and not by experimentally determined diffusion rates. Their arguments are based on (i) a coupled diffusion mechanism for Li, which has been postulated but ha...

U-Th zircon SHRIMP and U-Th-total Pb monazite CHIME ages of 6 typical samples were established among different rock types outcropped into the Chah-Dozdan batholith from Iran. The zircon population displays simple internal structures in samples of the Chah-Dozdan batholith. The zircon crystals have well-preserved magmatic characteristics. In all population, the rims display younger ages than the...

We present geochronological evidence in the eastern Himalayan syntaxis (Namche Barwa) for high-pressure (HP) granulite-facies metamorphism and explain its importance for understanding both the deep continental subduction of the Indian plate beneath Asia and its subsequent exhumation. The timing of peak and retrograde metamorphism in part constrains these processes but is debated. We present zir...