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Flagg Ranch exposure of the Lava Creek Tuff

November 2023 (approx.)

Detailed Description

Flagg Ranch exposure showing lower unknown ignimbrite (ash flow), the Lava Creek Tuff (LCT) ash fall deposit, and upper ignimbrite of the LCT. Thanks to work by Montana State University geologists, it is now known that the unknown ignimbrite was deposited immediately prior to the ash fall, with no significant time gap in between. Photo by Stacy Henderson (PhD student in Montana State University’s MOnSTER lab).


Public Domain.