Global Volcanism Program | Image GVP-03146
A major eruption about 6400 years ago produced the large Central Pumice Cone in the center of Newberry caldera, a pumice ring, and obsidian lava flows. The Interlake obsidian flow (on the far side of the left-hand lake, Paulina) originated from a vent on the north caldera wall and flowed onto the caldera floor and divided around Central Pumice Cone. The west lobe (seen here) flowed into Paulina Lake, while the east lobe flowed behind Central Pumice Cone into East Lake. The Game Hut obsidian flow was also erupted at this time.
Photo by Lee Siebert, 1984 (Smithsonian Institution).