While touring Lassen National Volcanic Park last month, we were treated to differing tempos of volcanic activity. The above photo shows Lassen Peak today, from the 1915 "devastated area" below its Mount St. Helens-style sideways blowout. Note the regrowth of trees in less than 100 years. Such scenes are testament to continuing volcanic activity in the Cascade Range.
The second photo shows an "erratic" boulder perched on glacially smoothed volcanic flows, the remarkable point being that this boulder was left behind at near 8.000 feet by a glacier during the retreat of the last glaciation, perhaps 10,000 years ago. The point of interest is that the two photos were taken on the flanks of the same volcano, which managed to leave undisturbed the ice-age erratic when it blew its top in another direction in 1915.
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