Take a tour through volcanic history on the edge of the Sierra Nevada near Mammoth Lakes, California. Between the tall granite peaks to the west and the Basin and Range province to the east, overlapping volcanic complexes imprint the landscape with a collection of craters, cones, and calderas. The area, still restless today, draws interest from geologists studying Earth’s processes and from planetary scientists exploring its commonalities with volcanic terrain elsewhere in our solar system.
A string of volcanic features between Mono Lake and Mammoth Mountain is visible along the left side of this Landsat image. Known as the Mono-Inyo Craters, this chain of about three dozen lava domes, lava flows, and tephra rings formed within the past 10,000 years. Explosive eruptions in the area date back even further, but evidence of those older events is no longer apparent at the surface.
Among the most recent activity in this chain, explosive eruptions formed Panum Crater near Mono Lake about 700 years ago. A strombolian eruption deposited a ring of pumice, ash, obsidian fragments, and other material around the vent. After that, a lava dome made of pumice and obsidian built up in the center, creating the concentric-circle pattern visible today.
South of the Mono-Inyo Craters, Mammoth Mountain is perhaps best known for its ample skiable terrain, but it has a volcanic side, as well. The mountain is made up of at least 25 overlapping lava domes. Its last magmatic eruptions took place about 57,000 years ago, but steam-driven phreatic eruptions and other unrest have occurred much more recently.
Scientists believe a magma intrusion beneath the mountain in 19 …