HR: 15:25h
AN: V12E-08 INVITED     [PDF]
TI: Quantifying Volcanic Emissions of Trace Elements to the Atmosphere: Ideas Based on Past Studies
AU: * Rose, W I
EM: raman@mtu.edu
AF: Geological Engineering \& Sciences, Michigan Technological University, 1400 Townsend Dr, Houghton, MI 49931 United States
AB: Extensive data exist from volcanological and geochemical studies about exotic elemental enrichments in volcanic emissions to the atmosphere but quantitative data are quite rare. Advanced, highly sensitive techniques of analysis are needed to detect low concentrations of some minor elements, especially during major eruptions. I will present data from studies done during low levels of activity (incrustations and silica tube sublimates at high temperature fumaroles, from SEM studies of particle samples collected in volcanic plumes and volcanic clouds, from geochemical analysis of volcanic gas condensates, from analysis of treated particle and gas filter packs) and a much smaller number that could reflect explosive activity (from fresh ashfall leachate geochemistry, and from thermodynamic codes modeling volatile emissions from magma). This data describes a highly variable pattern of elemental enrichments which are difficult to quantify, generalize and understand. Sampling in a routine way is difficult, and work in active craters has heightened our awareness of danger, which appropriately inhibits some sampling. There are numerous localized enrichments of minor elements that can be documented and others can be expected or inferred. There is a lack of systematic tools to measure minor element abundances in volcanic emissions. The careful combination of several methodologies listed above for the same volcanic vents can provide redundant data on multiple elements which could lead to overall quantification of minor element fluxes but there are challenging issues about detection. For quiescent plumes we can design combinations of measurements to quantify minor element emission rates. Doing a comparable methodology to succeed in measuring minor element fluxes for significant eruptions will require new strategies and/or ideas.
DE: 0370 Volcanic effects (8409)
DE: 8404 Ash deposits
DE: 8409 Atmospheric effects (0370)
DE: 8494 Instruments and techniques
SC: Volcanology, Geochemistry, Petrology [V]
MN: 2003 Fall Meeting