The Volcanic Tableland south of Long Valley Caldera (and north of Bishop, California) is composed of Bishop Tuff erupted about 76,000 years ago during the formation of the caldera. One pathological feature of this area is Pleistocene-aged drainage channels (it was wetter then) that flowed across the top of the tuff’s welded upper layer, but then were disrupted by faulting of the Volcanic Tableland since the Pleistocene.

There’s a lot of other stuff going on in this area. Zoom out a bit to see beautiful suites of en echelon normal faults disrupting these relatively young volcanic rocks.

Flash Earth Location here.