Japan Geoscience Union Meeting 2019

Presentation information

[E] Poster

S (Solid Earth Sciences ) » S-VC Volcanology

[S-VC34] Connecting magma dynamics in vent-conduit system with surface expression of volcanic eruption

Thu. May 30, 2019 3:30 PM - 5:00 PM Poster Hall (International Exhibition Hall8, Makuhari Messe)

convener:Takahiro Miwa(National research institute for earth science and disaster prevention), Nobuo Geshi(Geological Survey of Japan, The National Institute of Advanced Industrial Science and Technology)

[SVC34-P03] Eruptive trends and dynamics of remote volcanoes detected form space-based thermal data and SO2 emissions: a comparative analysis of Stromboli, Batu Tara and Tinakula volcanoes

*Corrado CIGOLINI1, Marco Laiolo1, Francesco Massimetti1,2, Maurizio Ripepe2, Diego Coppola1 (1.Department of Earth Sciences, University of Torino, Italy, 2.Department of Earth Sciences, University of Firenze, Italy)

Keywords:Remote volcanoes, satellite datasets, Volcanic Radiative Power, SO2 emissions, volcanic risk

South-Eastern Pacific has a large number of unmonitored volcanoes that may potentially produce large-scale eruptive events capable to affect highly-populated areas. Therefore, forecasting changes in volcanic activity in the light of historical time-series is a rather intriguing challenge for the space-based earth observations.
Batu Tara (Indonesia) and Tinakula (Solomon Island) are two poorly known volcanic islands with morphologies and reported short-term activities rather similar to the ones observed at Stromboli volcano (Italy). However, thanks to over a decade-long satellite data we are able to effectively compare the activity occurring at Stromboli (a unique natural laboratory and “open-vent” system) with those taking place at the above volcanoes.
We process and analyse the radiant flux (thermal activity) coupled with SO2 emissions (degassing activity) at these three volcanoes for over a decade. The combined analysis of Volcanic Radiant Power (from MODIS data) and SO2 burden (from OMI data) reveals different long-term eruptive trends, and contrasting ratio of gas vs. thermal emissions. In fact, the persistent open-vent explosive activity of Stromboli volcano is interrupted by flank effusions that periodically drain the degassed magma stored at shallow levels. On the other hand, the long-lasting exponential decay of both thermal and gas emissions observed at Batu Tara is consistent with the eruption of an “undegassed magma” from a deep, and likely a “closed” magma chamber. Finally, Tinakula volcano exhibits multiple year-long eruptive phases, characterised by evolving gas vs. thermal ratio correlated with an increasing eruptive intensity: thus suggesting the involvement of a volatile-zoned magma chamber with periodic phases of gas/magma accumulations.
Our results suggest that the combined analysis of satellite thermal/gas data is a useful tool for better understanding long-term volcanic dynamics and interpreting volcanic processes occurring at a shorter time-scale. We also stress that large satellite datasets on active volcanoes, available from different platforms, greatly enhance the opportunity to efficiently monitor remote volcanic targets in the attempt to mitigate volcanic risk.