Base of Bogus Lavas
Here are three images that show the base of the Bogus lava where it sits on tilted to soupy-looking yellow sediments. These images are from the cleft. That is the spot that led me to the inference that the Bogus lavas were deposited on landslid materials--note the tilted brown stuff evident in the panorama. Everywhere I have since seen the base of the Bogus (upstream) it rests on more obviously in situ volcanic rock or flat-lying soft rocks.