December 5, 2022 — Mauna Loa Fissure 3 Lava Flows Crossing Road

This image, taken midday during a helicopter overflight of Mauna Loa's eruption on December 5, 2022, shows a lava flow branching after it cuts across the Mauna Loa Access Road. The large blocks in channel are called lava boats. These are termed lava balls or lava boats and form when portions of the fissure 3 cone or levees break away and are rafted down stream. As they move along in the channel, additional lava can cool to their surface to form accretionary lava balls. USGS image by L. Gallant.