Pb isotope analyses of silicate rocks and minerals with Faraday detectors using enhanced-sensitivity laser ablation-multiple collector-inductively coupled plasma mass spectrometry

Abstract

208 Pb. Because of the low concentration of Pb in natural silicate rocks and minerals (typically sub parts per million to tens of parts per million), one or more ion counters (ICs, for Hg isotopes and the minor 204 Pb isotope) and Faraday cup (FC) detectors (for the major 206-208 Pb isotopes) have typically been used for analyses of isotope ratios (Kent, 2008a;

Origins of felsic magmas in Japanese subduction zone: Geochemical characterizations of tephra from caldera‐forming eruptions <5 Ma

“…The SRM612 standard was analyzed for every five unknown samples, and five points were usually analyzed for all of the tephras and standard glasses. The analytical results for the BCR‐2G, BHVO‐2G, and JR‐1 standard glasses correlated well with their reference values [ Chang et al ., ; Jochum et al ., ; Kimura et al ., ] (supporting information Table S3).…”

“…Pb isotope ratios, 207 Pb/ 206 Pb and 208 Pb/ 206 Pb, were analyzed by using an LA‐Multiple Collector (MC)‐ICP‐MS with the same DUV‐FsLA microsampler connected to a modified high‐sensitivity Neptune MC‐ICP‐MS (Thermo Scientific, Bremen, Germany) [ Kimura et al ., ]. All four Pb isotopes, 204 Pb, 206 Pb, 207 Pb, and 208 Pb, in addition to 202 Hg were measured with Faraday collectors equipped with high‐gain amplifiers by using a 10 12 Ω resistor for further improvement of analytical precision [ Kimura et al ., ].…”

“…We applied the standard bracketing method by using National Institute of Standards and Technology (NIST) SRM612 as the bracketing standard for mass bias corrections [Kimura et al, 2013]. Reference values of the Pb isotope ratios in SRM612 were obtained from Kent [2008].…”

Sr–Pb isotope compositions of lawsonites in a Pacheco Pass metagraywacke, Franciscan Complex, California

“…In-situ LA-MC-ICPMS Sr-Pb isotope analyses of lawsonites were performed at JAMSTEC, using an OK Laboratory OK-EX2000 193 nm nanosecond excimer laser with~10 mJ•cm −2 fluence, coupled to a MC-ICPMS (Neptune, Thermo Fisher Scientific) (Kimura et al, 2013a(Kimura et al, , 2013b. In both Sr-Pb isotope analyses, the spot sizes were 200 µm in diameter and the repetition rates were 10 Hz.…”

An improved U–Pb age dating method for zircon and monazite using 200/266 nm femtosecond laser ablation and enhanced sensitivity multiple-Faraday collector inductively coupled plasma mass spectrometry

“…2,[6][7][8] The ICP-MS technique is inferior to SHRIMP mainly from (1) elemental fractionation between U and Pb during laser ablation, 2,7,[9][10][11][12][13][14][15] or in the ICP plasma, 9,16,17 (2) icker noise in the ICP, 2,18 and (3) the non-linear response of the ion counter(s). 6,10,13,19,20 Elemental fractionation during laser ablation (referred to as downhole fractionation) has been examined intensively. Correction methods for downhole elemental fractionation have been examined.…”