Earthwatch scientist Dr. Hazel Rymer
Dr. Hazel Rymer, a volcanologist at The Open University, is presenting scientific evidence to suggest that Askja, an active volcano in North Iceland, is showing signs of a build-up to an eruption.
Dr. Rymer has measured gravity at Iceland's Askja volcano since 1985. Until 2007, the patterns were consistent; deflation of the ground (relaxation) and gravity decreases, which she interprets in terms of drainage of magma out of the Askja system. In 2008 this changed. The deflation reduced slightly and gravity began to increase, which she interprets as being due to new magma intruding beneath the volcano. This trend was confirmed in 2009.
Dr. Rymer says: "The results are consistent with seismicity which has been seen in the area since 2008. New magma accumulating beneath a volcano is what happens before an eruption. A critical amount needs to accumulate and we cannot say what that is. I can say that the rate of intrusion far exceeds the previous rate of drainage. For the last few hundred years, Askja has erupted every 40 years or so. It last erupted in 1961.
"In 1875, Askja erupted explosively, hurling ash as far as Scotland and Scandinavia and coated a large portion of Iceland in tephra (pumice). The crater left by this eruption is 200m deep and 5km wide."
This research was funded by Earthwatch and the Natural Environment Research Council (NERC).
VIDEO - Dr Rymer has for many years worked with Earthwatch volunteers and other researchers to understand and predict volcanic activity in Costa Rica and Nicaragua.”
Biography: Dr Hazel Rymer
Dr Hazel Rymer is presently Senior Lecturer in Environmental Geophysics based in the Department of Earth & Environmental Sciences at The Open University. She is also Associate Dean Science for Planning, External Relations & Media.