American Geophysical Union Meeting San Francisco

  • Martin Menzies (Participant)

Activity: Participating in or organising an eventParticipation in conference

Description

Tephra layers provide valuable isochronous markers in continental-marine correlations. Such correlations are only possible if the diagnostic chemistry of tephras are known, allowing them to be distinguished in time and space. Laser Ablation Inductively Coupled Plasma (LA-ICP-MS) is ideally suited for the analysis of volcanic tephra (i.e., vesicular glass) and the selection of diagnostic chemical parameters that allow proximal-distal matches. However tephras present an analytical challenge due to their size, the presence of microcrysts, vescicularity and the occurrence of stretched vesicles resulting in “thin” samples. LA-ICP-MS offers a solution with (a) high spatial resolution, with the ability to analyse 30-200 micron particles; (b) sensitivity and (c) low detection limits. We report the analytical precision and accuracy achieved in the MPI-DING reference glasses and in natural tephra samples using a number of different data reduction strategies. New micro-analytical data is presented for proximal deposits of the Thorsmork Ignimbrite (Tindorfajokull, Iceland) and compared to tephra from the North Atlantic marine cores.

The application of LA-ICP-MS to tephrochronology: advantages and methodology
PeriodDec 2009
Event typeOther
Sponsor