An HVO geologist looks through a thermal camera at Kīlauea's summit crater

An HVO geologist looks through a thermal camera at Kīlauea's summit crater lake during fieldwork on December 18. HVO has used thermal cameras for many years to better understand volcanic processes, such as emplacement and advancement of pāhoehoe lava flows, and activity at the lava lake that was present at Kīlauea's summit from 2008-2018. With the appearance of water at Kīlauea's summit, HVO geologists have an opportunity to study another type of process via thermal imagery, growth of a crater lake. Note the flat areas of lava flow surfaces beyond and above the lake. These are former sections of the floor of Halema‘uma‘u that subsided hundreds of meters (yards) during the 2018 collapse event. Yellow areas are regions of significant sulfur precipitation. HVO fieldwork in this closed area of Hawai‘i Volcanoes National Park is done with permission of the National Park Service to support public safety and further scientific understanding of Kīlauea Volcano. USGS photo by K. Mulliken.