title: Combined chemical separation of Lu, Hf, Sm, Nd, and Rees from a single rock digest: precise and accurate isotope determinations of Lu-Hf and Sm-Nd using multicollector-ICPMS.
abstract: A combined procedure for separating Lu, Hf, Sm, Nd, and rare earth elements (REEs) from a single sample digest is presented. The procedure consists of the following five steps: (1) sample dissolution via sodium peroxide sintering; (2) separation of the high field strength elements from the REEs and other matrix elements by a HF-free anion-exchange column procedure; (3) purification of Hf on a cation-exchange resin; (4) separation of REEs from other matrix elements by cation exchange; (5) Lu, Sm, and Nd separation from the other REEs by reversed-phase ion chromatography. Analytical reproducibilities of Sm-Nd and Lu-Hf isotope systematics are demonstrated for standard solutions and international rock reference materials. Results show overall good reproducibilities for Sm-Nd systematics independent of the rock type analyzed. For the Lu-Hf systematics, the reproducibility of the parent/daughter ratio is much better for JB-1 (basalt) than for two analyzed felsic crustal rocks (DR-N and an Archaean granitoid). It is demonstrated that this poorer reproducibility of the Lu/Hf ratio is truly caused by sample heterogeneity; thus, results are geologically reasonable.
authors.affiliation: Gruppe Isotopengeologie, Mineralogisch-Petrographisches Institut, Universität Bern, Switzerland. ilka@mpi.unibe.ch
authors.forename: Ilka C
authors.initials: IC
authors.lastname: Kleinhanns
authors.forename: Katharina
authors.initials: K
authors.lastname: Kreissig
authors.forename: Balz S
authors.initials: BS
authors.lastname: Kamber
authors.forename: Thomas
authors.initials: T
authors.lastname: Meisel
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Nägler
authors.forename: Jan D
authors.initials: JD
authors.lastname: Kramers