Supereruptions catastrophically eject 100s-1000s of km3 of magma to the surface in a matter of days to a few months. In this study, we use zoning in quartz crystals from the Bishop Tuff (California) to assess the timescales over which a giant magma body transitions from relatively quiescent, pre-eruptive crystallization to rapid decompression and eruption. Quartz crystals in the Bishop Tuff hav...

Fluid-inclusion measurements and textural relationships demonstrate that coarse-grained quartz and calcite from the upper part of The Geysers thermal system formed during the transition from liquid-dominated conditions to the modern vapor-dominated regime. The most diagnostic characteristics of these transition assemblages are: 1) evidence of quartz dissolution; 2) contemporaneous trapping of h...

Ž . High-purity aligned multi-walled carbon nanotubes MWNTs were synthesized through the catalytic decomposition of a ferrocene–xylene mixture at ;6758C in a quartz tube reactor and over quartz substrates, with a conversion of ;25% of the total hydrocarbon feedstock. Under the experimental conditions used, scanning electron microscope images reveal that the MWNT array grows perpendicular to the...

The transformation of quartz to stishovite has been studied by X-ray and optical examination of a series of experimentally shock-loaded specimens of a quartz-copper mixture. Shock pressures of 68 to 260 kb and peak temperatures of 320 ø to 870øK wer e achieved. Stishovite was identified from quartz shock-loaded above 90 kb; the quantity increases with increasing pressure, but is not dependent o...

We report the results of an experimental calibration of oxygen isotope fractionation between quartz and zircon. Data were collected from 700 to 1000 C, 10–20 kbar, and in some experiments the oxygen fugacity was buffered at the fayalite–magnetite–quartz equilibrium. Oxygen isotope fractionation shows no clear dependence on oxygen fugacity or pressure. Unexpectedly, some high-temperature data (9...

A detailed review on the development of quartz-enhanced photoacoustic sensors (QEPAS) for the sensitive and selective quantification of molecular trace gas species with resolved spectroscopic features is reported. The basis of the QEPAS technique, the technology available to support this field in terms of key components, such as light sources and quartz-tuning forks and the recent developments ...

The quartz plate calorimeters are considered as hadronic calorimeter options for upgrading Large Hadron Collider experiments. Previous studies have shown that quartz can resist up to 12 MGy of proton irradiation. Using uniformly distributed wavelength shifting fibers embedded the quartz plates are shown to solve the problem of low visible light production on Cherenkov process. Here, we report t...