The rapid heating, defocused beam technique: a CO2-laser-based method for highly precise and accurate determination of δ18O values of quartz

Spicuzza, Michael J.; Valley, John W.; Kohn, Matthew J.; Girard, Jean‐Pierre; Fouillac, Anne‐Marie

doi:10.1016/s0009-2541(97)00131-9

Cited by 91 publications

(54 citation statements)

References 17 publications

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“…Oxygen isotope ratios (δ 18 O, per mil notation) of 26 fresh, microphenocryst-free glass chips, covering the range of rock types (Table 1), were determined at the CO 2 -laser-fluorination laboratory at the University of Wisconsin, Madison, following methods described in Valley et al (1995) and Spicuzza et al (1998). Aliquots of 2.4-3.2 mg were treated with BrF 5 overnight, and then individually heated with a CO 2 laser in the presence of BrF 5 .…”

Section: Oxygen Isotope Analyses and Resultsmentioning

confidence: 99%

Volatile abundances and oxygen isotopes in basaltic to dacitic lavas on mid-ocean ridges: The role of assimilation at spreading centers

et al. 2011

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a b s t r a c t a r t i c l e i n f oMost geochemical variability in MOR basalts is consistent with low-to moderate-pressure fractional crystallization of various mantle-derived parental melts. However, our geochemical data from MOR highsilica glasses, including new volatile and oxygen isotope data, suggest that assimilation of altered crustal material plays a significant role in the petrogenesis of dacites and may be important in the formation of basaltic lavas at MOR in general. MOR high-silica andesites and dacites from diverse areas show remarkably similar major element trends, incompatible trace element enrichments, and isotopic signatures suggesting similar processes control their chemistry. In particular, very high Cl and elevated H 2 O concentrations and relatively light oxygen isotope ratios (~5.8‰ vs. expected values of~6.8‰) in fresh dacite glasses can be explained by contamination of magmas from a component of ocean crust altered by hydrothermal fluids. Crystallization of silicate phases and Fe-oxides causes an increase in δ 18 O in residual magma, but assimilation of material initially altered at high temperatures results in lower δ 18 O values. The observed geochemical signatures can be explained by extreme fractional crystallization of a MOR basalt parent combined with partial melting and assimilation (AFC) of amphibole-bearing altered oceanic crust. The MOR dacitic lavas do not appear to be simply the extrusive equivalent of oceanic plagiogranites. The combination of partial melting and assimilation produces a distinct geochemical signature that includes higher incompatible trace element abundances and distinct trace element ratios relative to those observed in plagiogranites.

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Section: Oxygen Isotope Analyses and Resultsmentioning

confidence: 99%

Volatile abundances and oxygen isotopes in basaltic to dacitic lavas on mid-ocean ridges: The role of assimilation at spreading centers

et al. 2011

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“…Oxygen was cryogenically purified and converted to CO 2 for analysis with a Finnigan MAT 251 mass spectrometer (Valley et al, 1995;Spicuzza et al, 1998). All analyses are standardized using the Gore Mountain Garnet standard (UWG-2) and the accepted d 18 O value of 5.8‰ (Valley et al, 1995).…”

Section: Analysis By Laser Fluorinationmentioning

confidence: 99%

“…Laser fluorination is a useful compliment to in situ analysis, especially given its high analytical accuracy and precision (0.07‰, 1SD; Valley et al, 1995;Spicuzza et al, 1998), however; this method requires 1-2 mg of sample per analysis (100-150 grains of quartz at 150-300 lm diameter). Thus, laser fluorination cannot measure single detrital grains or fine-scale (10-20 lm) zoning of d 18 O within the 10-100 lm overgrowths, which has been reported in the St. Peter Sandstone (Graham et al, 1996).…”

Section: Introductionmentioning

confidence: 99%

Optically continuous silcrete quartz cements of the St. Peter Sandstone: High precision oxygen isotope analysis by ion microprobe

Kelly

Kita

et al. 2007

Geochimica et Cosmochimica Acta

107

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“…Oxygen was converted to CO 2 gas, and analyzed on a MAT 253 mass spectrometer integrated with the laser line. Quartz grains were measured using the rapid heating defocused beam technique which was demonstrated to produce d 18 O values independent of grain size (Spicuzza et al, 1998). Quartz grains showed no crystal jumping, which suggests they were largely free of fluid inclusions, and yields were $100%, similar to Bishop Tuff quartz.…”

mentioning

confidence: 99%

Experimental calibration of oxygen isotope fractionation between quartz and zircon

Trail

Bindeman

Watson

et al. 2009

Geochimica et Cosmochimica Acta

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The rapid heating, defocused beam technique: a CO2-laser-based method for highly precise and accurate determination of δ18O values of quartz

Cited by 91 publications

References 17 publications

Volatile abundances and oxygen isotopes in basaltic to dacitic lavas on mid-ocean ridges: The role of assimilation at spreading centers

Volatile abundances and oxygen isotopes in basaltic to dacitic lavas on mid-ocean ridges: The role of assimilation at spreading centers

Optically continuous silcrete quartz cements of the St. Peter Sandstone: High precision oxygen isotope analysis by ion microprobe

Experimental calibration of oxygen isotope fractionation between quartz and zircon

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