The 2019 Eruption Dynamics and Morphology at Ebeko Volcano Monitored by Unoccupied Aircraft Systems (UAS) and Field Stations

Abstract

Vulcanian explosions are hazardous and are often spontaneous and direct observations are therefore challenging. Ebeko is an active volcano on Paramushir Island, northern Kuril Islands, showing characteristic Vulcanian-type activity. In 2019, we started a comprehensive survey using a combination of field station records and repeated unoccupied aircraft system (UAS) surveys to describe the geomorphological features of the edifice and its evolution during ongoing activity. Seismic data revealed the activity of the volcano and were complemented by monitoring cameras, showing a mean explosion interval of 34 min. Digital terrain data generated from UAS quadcopter photographs allowed for the identification of the dimensions of the craters, a structural architecture and the tephra deposition at cm-scale resolution. The UAS was equipped with a thermal camera, which in combination with the terrain data, allowed it to identify fumaroles, volcano-tectonic structures and vents and generate a catalog of 282 thermal spots. The data provide details on a nested crater complex, aligned NNE-SSW, erupting on the northern rim of the former North Crater. Our catalog of thermal spots also follows a similar alignment on the edifice-scale and is also affected by topography on a local scale. This paper provides rare observations at Ebeko volcano and shows details on its Vulcanian eruption style, highlighting the relevance of structural and morphologic control for the geometry of craters and tephra fallout as well as for structurally controlled geothermal activity.

Mechanism of the historical and the ongoing Vulcanian eruptions of Ebeko volcano, Northern Kuriles

“…We also placed a geophone seismometer and time-lapse monitoring cameras to record occurrence of explosions. More details on location and type of the instrumentation as well as the processing methods and geophysical records are provided in Walter et al ( 2020 ).…”

“…16–17, 2011 2011–2015 2015–Oct. 2016 Bread-crust bombs 5 years Kotenko et al 2019 , 2020 ; Walter et al 2020 2016–2020 Oct. 19, 2016–2020 (continues) …”

“…4c ). It gradually enlarged and was named “new north crater” by Walter et al ( 2020 ). Since August 2018, all the explosive activity of Ebeko occurs only inside the new north crater (Figs.…”

“…Vent locations of 1958, 1963, and 1965 after Khramova ( 1987 ). Locations of fumaroles and hot springs (yellow diamonds) were identified by the thermal camera of UAS (Walter et al 2020 ). Green triangles indicate sampling sites of fresh bread-crust bombs.…”

“…We sampled the erupted pyroclasts, installed seismometers and monitoring cameras, and mapped the terrain using unoccupied aircraft systems (UAS) together with optical and infrared cameras. The seismical and UAS data have shown dimensions and structures of the newly forming crater as well as the distribution and deposition of erupted materials (Walter et al 2020 ).…”