3) Leif Karlstrom

Leif Karlstrom, Associate Professor, University of Oregon

Monday September 25th; 3 PM

Host: Jeffrey Johnson

Title: Excitation and resonance of very long period seismicity at Kīlauea volcano

Abstract: The study of volcanoes involves spatial and temporal scales that are often hidden and outside the human experience. As a result, the field of volcanology is built around a wide range indirect methods to infer dynamics. In this talk I will discuss the problem of inferring geometry of and fluid motion within conduit and crack structures beneath the surface of the Earth. In particular, I will discuss the phenomenology of fluid resonance in elastic-walled tubes and cracks containing bubbly magma, and a prolonged (10 year) eruptive sequence at Kīlauea volcano, Hawaii. This eruptive sequence was characterized by nearly continuous open vent volcanism with an active lava lake, culminating with caldera collapse in 2018. During the eruption, rockfalls from the summit crater walls onto the lava lake excited resonant oscillations with remarkable characteristics in the “Very Long Period” frequency band between ~3-40 seconds. We have developed a physics-based modeling framework to invert thousands of these seismic signals along with a variety of other observables during the eruption, resulting in inference of variable magma temperature and volatile contents from days to years. In particular, we infer that the conduit and shallow magma reservoir cooled by tens of degrees between 2008-2018, and regularly exhibited volatile contents far in excess of equilibrium solubility. Throughout the talk I will make liberal use of “sonification”, highlighting how a combined auditory and visual representation of data can lead to new insights and appreciation of the hidden dynamics of volcanoes.

Bio: Leif Karlstrom is an Earth Scientist at the University of Oregon. He studies the fluid and solid mechanics of volcanoes, glaciers, and landscapes. He leads the “Volcano Listening Project”.


Journal Article: 

PAPER_sciadv_Crozier_2022.pdf