The 2018/19 eruption of Kadovar Volcano, Papua New Guinea - multi-sensor satellite imagery analysis of the growth and collapse of a littoral lava dome

Kurzfassung

Growing lava domes and volcanic islands become structurally unstable, associated with sectoral collapses, explosive volcanism and related hazards. We present the rare case of a growing and collapsing lava dome at Kadovar Volcano, a small inhabited volcanic island which is part of the Schouten Islands, at the western end of the Bismarck Volcanic Arc, north of Papua New Guinea. The first confirmed historical eruption at Kadovar began on January 5, 2018 and was monitored by thermal, synthetic aperture radar (SAR) and optical satellite sensors. Our analysis shows that Kadovar began a new episode of volcanic activity at the central crater and then also at the eastern coast of the island, where the birth of a new emerging lava dome was monitored. We analyze changes occurring on the island and the littoral lava dome and identify that after dome growth, parts of the island and about 80% of the littoral lava dome collapsed eastwardly into the ocean on February 9, 2018. This collapse caused a small tsunami that hit the neighboring islands. The littoral lava dome then re-grew at a slower rate and reached a final area of ~40,000 m² by May 2, 2018, which corresponds to an estimated subaerial volume of the lava dome of ~400,000 m³. This study provides details on the rapid growth and collapse of a peripheral lava dome and a destabilization episode in an island and dome sector. We demonstrate the importance of satellite data for the investigation of remote volcanic islands.