A couple weeks ago, I gave a presentation on the geology of the Willamette Valley. I prefer to simply use slides and talk to the audience directly, rather than powerpointing them to death. My own personal feeling is that Powerpoint kills spontaneity, takes the focus off the speaker and content, and enforces a linearity of thinking I find offensive. On the other hand, the style I use means I can never give the same talk twice, nor necessarily be able to recapture certain moments, no matter how much I'd like to (and we did have a couple of those, which I'll bring up in later parts). On the other other hand, I'm free to come up with new "perfect moments" whenever inspiration hits.
So I've decided to attempt, not to recapture that talk, but to post the
images I used, reiterate some of the important points, mention locations
when appropriate, and include some links to relevant material. Most of the links will be from a post last week, but they'll be better
organized by topic in this series.
The talk was organized into several segments, including Ice Age Floods, Stream Processes and Fluvial Landforms, Rock Materials of the Willamette Valley and Environs, and a brief overview of (what we were expecting to see at) Silver Falls State Park Geology. A final portion that I was not able to cover during the talk was on non-tectonic geologic hazards (Bob Lille covered earthquakes and volcanoes), with emphasis on mass movement and flooding. (Note: all the images will get much larger if you click on them, and you may find it more convenient to right click and open images in new tabs, so you don't need to reload the whole blog when you come back)
FlashEarth. Above is a satellite imagery map of Washington, Northern Oregon, Northern Idaho and Western Montana. Almost the entirety of the area affected by Glacial Lake Missoula and the Missoula floods is shown. Since I'm not entirely certain how far east the lake extended, it may have gone off the right edge of the image.
I commented in an older post that this is, to me, the single most staggering and incomprehensible statistic I know of regarding these floods... to stand on Crown point, look across the gorge, and picture everything up to that point under water is mind-blowing.
The deposit to the south is called Alameda Ridge, and I-84 to the lower left is following Sullivan's Gulch, a drainage channel that the floods created.
terroir, I'll point out that my understanding is that for Pinot Noir grapes, at least, the lateritic soils developed on highly weathered Columbia River Basalt produces a better flavor
argillte, and particularly the section on the Belt supergroup, which is the likely source of this rock)
Photo from (though not by) Dana Hunter.This was from the last day of Dana's visit in July of this year, and if you click for the full-size photo, you can get a good sense of how terribly exhausted I was at this point. But happy.
The upper cross hair is just onto this rock in this FlashEarth link)
A Bright Moon Impact
1 day ago