title: Thallium as a tracer for preindustrial volcanic eruptions in an ice core record from Illimani, Bolivia.
abstract: Trace element records from glacier and ice sheet archives provide insights into biogeochemical cycles, atmospheric circulation changes, and anthropogenic pollution history. We present the first continuous high-resolution thallium (Tl) record, derived from an accurately dated ice core from tropical South America, and discuss Tl as a tracer for volcanic eruptions. We identify four prominent Tl peaks and propose that they represent signals from the massive explosive eruptions of the "unknown 1258" A.D. volcano, of Kuwae ( approximately 1450 A.D.), Tambora (1815 A.D.), and Krakatoa (1883 A.D.). The highly resolved record was obtained with an improved setup for the continuous analysis of trace elements in ice with inductively coupled plasma sector field mass spectrometry (ICP-SFMS). The new setup allowed for a stronger initial acidification of the meltwater and shorter tubing length, thereby reducing the risk of memory effects and losses of analytes to the capillary walls. With a comparison of the continuous method to the established conventional decontamination and analysis procedure for discrete samples, we demonstrate the accuracy of the continuous method for Tl analyses.
authors.affiliation: Department of Chemistry and Biochemistry, University of Bern, Switzerland. kellerhals@climate.unibe.ch
authors.forename: Thomas
authors.initials: T
authors.lastname: Kellerhals
authors.forename: Leonhard
authors.initials: L
authors.lastname: Tobler
authors.forename: Sabina
authors.initials: S
authors.lastname: Brütsch
authors.forename: Michael
authors.initials: M
authors.lastname: Sigl
authors.forename: Lukas
authors.initials: L
authors.lastname: Wacker
authors.forename: Heinz W
authors.initials: HW
authors.lastname: Gäggeler
authors.forename: Margit
authors.initials: M
authors.lastname: Schwikowski
mesh_terms: D001838:Bolivia; D004784:Environmental Monitoring / Q000379:methods*; D049668:History, 15th Century; D049669:History, 16th Century; D049670:History, 17th Century; D049671:History, 18th Century; D049672:History, 19th Century; D049673:History, 20th Century; D049690:History, Ancient; D049691:History, Medieval; D007053:Ice / Q000032:analysis*; D013793:Thallium / Q000737:chemistry*; D018707:Volcanic Eruptions / Q000266:history*
chemical_list: D007053:Ice; D013793:Thallium