Frozen Basalt Lavafall An interesting view of the west wall of the Lua Poholo 'sub'-pit within Mauna Loa's North Pit. Note how a flow of lava more recent in age than the pit has spilled into it, then solidified.
This image is from the presentation "A Hawaiian Kaleidoscope - The Big Island: Volcanoes, Mauna Loa Climb, Heiaus and Beach Relaxation".