Project Details
Projekt
Viscous flow of magmas from Unzen volcano, Japan - Implications for magma ascent and emplacement
Applicant
Dr. Kai-Uwe Hess
Subject Area
Mineralogy, Petrology and Geochemistry
Term
from 2005 to 2009
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 5447048
The lack in understanding the flow behaviour of ascending highly viscous conduit magmas is a major drawback in forecasting explosive volcanic eruptions. Due to the very recent development of a unique high-load, high-temperature deformation apparatus it is now, for the first time, possible to determine the effective non-Newtonian viscosity of rhyolitic multi-phase magmas at strain rates actually occurring prior to and during volcanic eruptions. This opportunity comes when cores from a section of Unzen’s conduit were recently acquired. Taken together, the new technique and the new sample availability provide a unique opportunity to advance the rheological understanding of Unzen. The new data will enable the elaboration of complete volcanic eruption models at Unzen. Such models have important implications for the interpretation of (a) shallow volcanic earthquakes (e.g. low frequency events) and their potential use as indicators for near-future volcanic eruptions, (b) self-sealing mechanisms of the Unzen conduit, and (c) the poorly understood displacement mechanism of Unzen lava lobes, potentially indicative of non-Newtonian flow behaviour.
DFG Programme
Infrastructure Priority Programmes
Participating Person
Professor Dr. Donald Bruce Dingwell
