You can still see the ash layer from the soon-to-be-Crater Lake eruption hundreds of miles away on hillsides and in gullies. [0] It's as much as 8 inches thick

You can still see the ash layer from the soon-to-be-Crater Lake eruption hundreds of miles away on hillsides and in gullies. [0] It's as much as 8 inches thick in the Okanogan in Washington State. That's 400+ miles away. [0] https://en.wikipedia.org/wiki/Mazama_Ash https://en.wikipedia.org/wiki/Mazama_Ash