Or at least Rattlesnake Ridge
http://www.yakimaherald.com/news/local/watch-aerial-video-shows-rattlesnake…
If you read the articles listed below the video you'll get more detail.
I've had email conversations with Steve Reidel. Nick couldn't answer my question so he told me to ask Steve. 😉 He is a local expert on our "Big Black Boring Rock", i.e. the basalt that covers much of Washington & Oregon.
