Outside The Interzone: Anniversaries

Showing posts with label Anniversaries. Show all posts

Monday, September 22, 2014

Geo 730: September 22, Day 630: Dana Makes Contact

Jumping ahead a bit in covering our July trip this year, I realized that in the two previous anniversary posts, I should have included at least one photo of Dana. And since this is one of my favorite photos from our recent trip, here you go. Why favorite? Because she's so obviously happy to be here, pointing at the contact above her head, like Vanna White doing a show called "Wheel of Earth History."

But there's some very pleasing geology here, too. Regular readers may remember that in last year's series, I posted a couple of photos of Elephant Rock, at Seal Rock State Park. I was initially frustrated in trying to explain vertical jointing in a vertically tabular sheet of basalt, but I finally generated an idea of how that could happen: it wasn't a dike, as I'd long thought, but an eroded mass that was originally horizontally cylindrical. I couldn't support that with evidence, but it was plausible, and explained those vertical columns.

Now I have evidence! Dana is standing in front of (Miocene) Astoria Formation, and above and to the left of where she's pointing, you can see the lower contact of a Columbia River Basalt flow. AND... it's tilted just as one would expect if that invasive episode was originally cylindrical! (There are also some nice cross-beds in the lower right, but I have better photos of those for later.)

So not only did this make Dana happy, it made me happy, too.

Photo unaltered. July 15, 2014. FlashEarth Location.

Sunday, September 21, 2014

Geo 730: September 21, Day 629: Anniversary Beach

Here we're at Sutton Beach/Creek, a recreation area on Siuslaw National Forest land. We're looking north to the headlands between Florence and Yachats, which are composed of Yachats Basalt, about 35-30 million years old. I've just realized, looking through these photos, that I haven't included many of them from this area on this trip, although I did thoroughly cover a later stop at Cape Perpetua (April 8 to 28 in the Geo 365 Series), about 15 miles north of here. So there's geology in the background, but is there any in the foreground? Yes, though you'd need a bit more context to see that. I chose this photo because I like the dramatically windswept tree, but if I had turned 90 degrees to the left, you'd see a stream and open beach; this area has only been colonized by plants within the past couple of centuries. There's no higher ground between here and the ocean, thus nothing protecting the vegetation from fierce storm winds, which are frequent and persistent in the winter. If you're unfamiliar with the area, this isn't necessarily evident from this photo, but if you have spent any time along the Oregon Coast, this sort of setting has clear implications for the geologic context where it's found. If you want to get a sense of what the solid earth materials are doing, you have to have a strong understanding of what the other earth components- living, liquid and gaseous- are doing, too.

Photo run through Paint.net's AutoLevel routine for contrast and saturation. September 20, 2010. FlashEarth Location.

Saturday, September 20, 2014

Geo 730: September 20, Day 628: Anniversary Tyee

Four years ago today, I met Dana Hunter for the first time. We went up Marys Peak to get a good look at a transect of Oregon's Coast Range Geology. So I'm interrupting the current series in the Newport area for a couple of days. (The following day, we went to Florence and the headlands between Florence and Yachats.) Above, we see steeply dipping beds of Tyee Formation along Route 34, a couple miles east of Alsea Pass. This outcrop is close to the Corvallis Fault; it lies just to the west here, and crosses the Coast Range crest on the west side of Alsea Pass.

Photo unaltered. September 20, 2010. FlashEarth Location.