On our way up Compton Peak the other day, my field crew spotted some fibrous growths of ice growing up and out of the ground (perpendicular to the surface of the mountain): (Joe’s hand lens for scale.) The fibrous habit made me think of asbestos, and then I wondered whether the different shapes of ice … Read more
The final episode of the 10-part “Geology of San Francisco” series concludes with a visit to the spot where the San Andreas Fault runs off the edge of California and down into the sea. Mussel Rock, site of the opening vignette of John McPhee’s “Assembling California” is located there.
In January, a large landslide occurred in the Hunza Valley of Pakistan’s Karakoram Range, near the village of Attabad. Like the Madison River landslide in Montana (1959), or the Gros Ventre landslide in Wyoming (1925), a river was dammed by the slide debris, and the impounded waters began to rise. At Gros Ventre, the landslide-dammed … Read more
Small-scale debris flows as a muddy slurry flowed over weathered-out chunks of the Bishop Tuff. Probably about two days old. Southern edge of the Volcanic Tableland, last September.