title: Laser Ablation - Accelerator Mass Spectrometry: An Approach for Rapid Radiocarbon Analyses of Carbonate Archives at High Spatial Resolution.
abstract: A new instrumental setup, combining laser ablation (LA) with accelerator mass spectrometry (AMS), has been investigated for the online radiocarbon ((14)C) analysis of carbonate records. Samples were placed in an in-house designed LA-cell, and CO2 gas was produced by ablation using a 193 nm ArF excimer laser. The (14)C/(12)C abundance ratio of the gas was then analyzed by gas ion source AMS. This configuration allows flexible and time-resolved acquisition of (14)C profiles in contrast to conventional measurements, where only the bulk composition of discrete samples can be obtained. Three different measurement modes, i.e. discrete layer analysis, survey scans, and precision scans, were investigated and compared using a stalagmite sample and, subsequently, applied to terrestrial and marine carbonates. Depending on the measurement mode, a precision of typically 1-5% combined with a spatial resolution of 100 μm can be obtained. Prominent (14)C features, such as the atomic bomb (14)C peak, can be resolved by scanning several cm of a sample within 1 h. Stalagmite, deep-sea coral, and mollusk shell samples yielded comparable signal intensities, which again were comparable to those of conventional gas measurements. The novel LA-AMS setup allowed rapid scans on a variety of sample materials with high spatial resolution.
authors.affiliation: Laboratory of Inorganic Chemistry, D-CHAB, ETHZ , Vladimir-Prelog Weg 1, 8093 Zurich, Switzerland.|Laboratory of Ion Beam Physics, ETHZ , Otto-Stern Weg 5, HPK, 8093 Zurich, Switzerland.
authors.forename: Caroline
authors.initials: C
authors.lastname: Welte
authors.affiliation: Laboratory of Ion Beam Physics, ETHZ , Otto-Stern Weg 5, HPK, 8093 Zurich, Switzerland.
authors.forename: Lukas
authors.initials: L
authors.lastname: Wacker
authors.affiliation: Laboratory of Inorganic Chemistry, D-CHAB, ETHZ , Vladimir-Prelog Weg 1, 8093 Zurich, Switzerland.
authors.forename: Bodo
authors.initials: B
authors.lastname: Hattendorf
authors.affiliation: Laboratory of Ion Beam Physics, ETHZ , Otto-Stern Weg 5, HPK, 8093 Zurich, Switzerland.
authors.forename: Marcus
authors.initials: M
authors.lastname: Christl
authors.affiliation: Institute for Environmental Physics, University of Heidelberg , D-69120 Heidelberg, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Fohlmeister
authors.affiliation: Institute of Geology, Mineralogy and Geophysics, Ruhr-University Bochum , D-44801 Bochum, Germany.
authors.forename: Sebastian F M
authors.initials: SF
authors.lastname: Breitenbach
authors.affiliation: School of Earth Sciences, University of Bristol , Bristol BS8 1TH, U.K.
authors.forename: Laura F
authors.initials: LF
authors.lastname: Robinson
authors.affiliation: NOAA Fisheries, Pacific Islands Fisheries Science Center, Honolulu, Hawaii 96818, United States.
authors.forename: Allen H
authors.initials: AH
authors.lastname: Andrews
authors.affiliation: Senckenberg am Meer, Abteilung Meeresforschung, D-26382 Wilhelmshaven, Germany.
authors.forename: André
authors.initials: A
authors.lastname: Freiwald
authors.affiliation: Earth and Environmental Sciences and Lamont-Doherty Earth Observatory, Columbia University , Palisades, New York 10964, United States.
authors.forename: Jesse R
authors.initials: JR
authors.lastname: Farmer
authors.affiliation: Laboratory of Ion Beam Physics, ETHZ , Otto-Stern Weg 5, HPK, 8093 Zurich, Switzerland.
authors.forename: Christiane
authors.initials: C
authors.lastname: Yeman
authors.affiliation: Laboratory of Ion Beam Physics, ETHZ , Otto-Stern Weg 5, HPK, 8093 Zurich, Switzerland.
authors.forename: Hans-Arno
authors.initials: HA
authors.lastname: Synal
authors.affiliation: Laboratory of Inorganic Chemistry, D-CHAB, ETHZ , Vladimir-Prelog Weg 1, 8093 Zurich, Switzerland.
authors.forename: Detlef
authors.initials: D
authors.lastname: Günther