Saturday, February 23, 2013

Geo 365: Feb. 23, Day 54: Winter Rim, Summer Lake

Winter Rim rises over the town of Summer Lake, Oregon. The actual lake, Summer Lake, is behind us in this view, taken from a city park/wayside that's almost as large as the town itself. I've never been able to tell exactly what's going on in that outcrop up on the rim. I think the lighter layers are tuffaceous sediments, and the darker material lava flows, but from this distance- and I've never been closer than this spot- I'd rather not speculate any further than that.

Photo unmodified. August 20, 2011. FlashEarth location.

Followup: Commenter Lyle left a link to a field trip abstract, that like so much in geology, sounds dry and technical. But if you understand it, crazy scary and amazing. Quake-induced landslides, with volumes in the range of cubic kilometers and run-outs in the range of kilometers. My response was that "Summer Lake just got a whole lot more dangerous-looking!"

2 comments:

Lyle said...

I found an abstract that confirms your hypothesis, it discusses the landslides that result from the lave overlying the tuffaceous sediments:
http://fieldguides.gsapubs.org/content/15/203.abstract

Lockwood said...

Whoa! Thanks for that link, Lyle. Scary stuff. Summer Lake just got a whole lot more dangerous-looking!