The Kilauea 2018 eruption: Insight from surface deformation and topography change observations
Abstract
The 2018 eruption of Kīlauea volcano represents one of its most significant sequence of events in the past 200 years. As of the writing of this abstract large-scale summit caldera collapse and fissure lava effusion in the lower East Rift Zone (ERZ) are ongoing. We present preliminary data analysis of surface deformation (e.g. GPS, InSAR) and topography change (e.g. lava effusion, caldera collapse) from a number of instruments. Interferometric synthetic aperture radar (InSAR) surface deformation data are from: the Canadian Space Agency's RADARSAT-2, the European Space Agency's Sentinel-1A/B, the Italian Space Agency's COSMO-SkyMed, and the Japan Aerospace Exploration Agency's ALOS-2 satellites. We also include GPS data analysis from the local network. Surface topography changes are being acquired from a NASA G-III jet with the GLISTIN-A instrument: a single-pass interferometric, Ka-band, SAR. To date there have been six acquisitions between May 18 and June 18, with more acquisitions likely later in 2018. As of June 18 we calculated roughly 250 million m3 lava effusion. We derived this through an estimation of the pre-eruption vegetation height via the pre-eruption GLISTIN topography relative to a LiDAR bare earth topography model, a mask of the flow footprint at each date, and the GLISTIN height change relative to the pre-eruption topography. The geodetic data constrain the temporal and spatial evolution of the eruption from the initial InSAR-observed deflation of the middle ERZ on May 1, with dike propagation toward the initial fissure eruption location that began on May 3. An M6.9 earthquake, May 4, beneath the south flank further enriches the sequence of events while also complicating the InSAR deformation interpretation and modeling. Preliminary data reveal that the ALOS-2 InSAR are especially important in the lower ERZ where the fissure eruptions have occurred, while RADARSAT-2 has provided important constraints on the initial pre-eruption magma movement in the middle ERZ. As the eruption has endured, Kīlauea summit deflation has become an increasing part of the story. We will present preliminary source models constrained by the InSAR and GPS geodetic data to infer changes in the magma plumbing system. We will compare these source model volume change estimates with the airborne InSAR topography change measurements of the lava flow volumes as well as independent estimates of lava effusion rates. Future work will use the geodetic and effusion data to constrain physical models for the entire system.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFM.V21B..05L
- Keywords:
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- 8499 General or miscellaneous;
- VOLCANOLOGY