This is Winter Falls, on the next drainage south from North Falls, so named due to the fact it's more of a steady drip than a waterfall by mid summer. There are at least two Columbia River Basalt flows, with the boundary visible as the recess through the upper middle of this view of the cliff. About halfway up from that is another boundary, but I'm suspicious that's a textural change within a single flow- from hackley jointing to columnar jointing, for example, rather than a third lava flow. Something I hadn't noticed until reviewing the photos, though, is that the upper portion of the lower flow and lower portion of the upper flow appear to have a pillow-like aspect to them... but I can't... quite... tell... at the best resolution of this shot. It's also at a spot where hikers are making a prolonged, steep climb, and all they can think about is "Get me to the top, now!" So not the best spot for thinking about what you're seeing, geologically. But if I ever get back here, pillow basalt is definitely something I'll seek evidence for or against in outcrops closer to the trail where I can get a better look at textures.
Photo unmodified. August 30, 2012.
FlashEarth Location
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