Outside The Interzone: Oct 20, 2013

Saturday, October 26, 2013

Geo 365: Oct. 26, Day 299: Devils Punchbowl Terrace

Here, as at Shore Acres, we see sandy- likely, beach- deposits over a flat terrace on Astoria Formation sediments. It's not obvious in this view, but these rocks are dipping to the northwest, so the contact between the semi-consolidated sand and the underlying Miocene rock is an angular unconformity of sorts. As I mentioned at the above link, it's not clear to me whether "angular unconformities" necessarily require both the tilted and overlying material to be fully lithified. It should be pretty clear from the ease with which the sand is eroded by spray from breaking waves that it can't really be considered "rock."

Yaquina Head photobombs the left horizon as well, another example of CRB reaching the location of the modern coastline. If you look closely, you may be able to pick out the lighthouse there.

Photo unmodified. May 6, 2013. FlashEarth location.

Friday, October 25, 2013

Geo 365: Oct. 25, Day 298: Otter Rock From Devils Punchbowl

After we left Hatfield Marine Science Center, we headed north to Devils Punchbowl, prior to driving up to Otter Rock- the high point in the left-middle of this panorama. (size options here- right click on the image) There's a lot going on in this photo. The most extraordinary aspect is the ring dike, displayed as a series of sea stacks outward and to the south (toward the viewer) of Otter Rock, where Columbia River Basalt reached the Pacific Ocean, flowed out onto the then-accumulating sediments of the Astoria Formation, and plunged into them, creating so-called invasive dikes. Not visible from this viewpoint, but clearly shown by the photo at the first link, there is actually a pair of ring dikes and some radial dikes as well. The sediments of the Astoria Formation have been tilted to the west at this location, and two generations of marine terraces have been developed on those rocks. What appears to be sandy beach deposits create an angular unconformity on the elevated terrace, where The Inn at Otter Crest has been built. In addition to the elevated terrace of Otter Crest, it looks as if there's a somewhat more poorly developed terrace at roughly the same elevation in the CRB headland beyond Otter Rock. A small waterfall drops to the beach this side of the stairway from the inn. Finally, I can't see enough detail to be absolutely certain, but there are number of linear grooves that are likely faults across the modern, sea-level terrace.

Like I said, a lot going on here.

Photo unmodified. May 6, 2013. FlashEarth location.

Thursday, October 24, 2013

Geo 365: Oct. 24, Day 297: Lava Shelf

A rock younger than me... a first for this series, I think. I'm pretty sure we're looking at the lower side- that is, down-facing side- of the shelf here, based on the morphologies of the "drips." As I mentioned yesterday, I only got a few photos here; the other of interest, a black smoker, can be seen in the May 6 Geo 365.

Photo unmodified. May 6, 2013. FlashEarth location.

Wednesday, October 23, 2013

Geo 365: Oct. 23, Day 296: Abalone

I hadn't been into the Hatfield Marine Science Center in years, and I was pretty impressed. I think abalones are grazers, crawling along on hard, rocky substrates, eating algae growing on those surfaces. I had never seen live ones before, and even without the mother-of-pearl for which they're known visible, I thought they were quite beautiful.

There are many displays on various aspects of oceanography here, especially the biological and geological ones. I only took a few photos, and we sort of rushed through. The facility has a lot more than I recalled, and deserves more time than we had to give it that day.

Photo unmodified. May 6, 2013. FlashEarth location.

Tuesday, October 22, 2013

Geo 365: Oct. 22, Day 295: Inside the Dock

Since the Tohoku tsunami dock was cut in to sections to facilitate removal, the section now displayed as a memorial to the victims of that disaster is open in the back. Here Dana stands in its cavernous interior, providing a sense of scale. Incidentally, in addition to yesterday's photo, the exterior and a better overview of the entire exhibit can be seen in the May 7 post.

Photo unmodified. May 6, 2013. FlashEarth location.

Monday, October 21, 2013

Geo 365: Oct. 21, Day 294: The Dock

The tsunami dock that floated across the Pacific Ocean following the March 11, 2011 Tohoku earthquake has not lost its power to stop me in my tracks. In being cut up and put into a more formal "shrine" sort of setting, I think it lost some of its raw power, but I can't see it without being reminded of the devastation and lives lost. That said, I do wish there had been time and resources available to find a way to anchor it in the location where it actually made landfall.