April 21, 2023 — Geologist surveys newly exposed lavas and tephra in the wall of Kīlauea caldera

Hawaiian Volcano Observatory geologists documented newly exposed lava flows and tephra layers in the northwest wall of Kīlauea caldera during a field visit the morning of April 21, 2023. These new exposures will help us better understand Kīlauea's long term eruptive history, which alternates between effusive periods (producing lava flows) and explosive periods (producing tephra such as ash). USGS Photo by K. Lynn.