Saturday, June 21, 2014

Saturd80's: True Stories Edition

From David Byrne's (along with Talking Heads) 1986 movie, True Stories. The studio album was done by Talking Heads, but in the movie, many of the songs were sung by the actors.

Puzzling Evidence

Wild Wild Life

Radio Head (I hadn't realized the group named themselves after this song)

Geo 730: June 21, Day 537: Cold Basin

I thought this "windmill" looked pretty wimpy for electricity generation, and was wondering what it could realistically contribute, given the height of the peaks around this basin. I also didn't notice the propane tank at its base, which, really, should have been a giveaway. While this area is not too high in elevation (I'm estimating between 600-1000 feet; the closest value I can find with resources at hand is for Roseburg, at 528 feet), cold air tends to accumulate on the valley floor. Inversions are common in Oregon's western valleys, but the air, by definition, is warmer higher up. The "windmill" is simply to stir up the cold air when there's a danger of frost, and mix it with warmer overlying air. I'm also guessing there's a burner associated with the propane tank to warm everything a bit.

Photo unmodified. March 9, 2012. FlashEarth location.

Geo 730: June 20, Day 536: Giardet

This is the Giardet Vineyard and Winery. The central Willamette Valley is the better-known area for Oregon wineries, but we found on this trip that there is a rapidly growing wine area around- particularly to the west of- Roseburg. I'm not wine-knowledgeable, and don't know what the terroir of this area does for grapes, but the number and apparent success of vineyards in this area suggests that there's something pretty good about it. And the approach that this particular vineyard uses to get their soils was new and very interesting to me...

Photo unmodified. March 9, 2012. FlashEarth location.

Friday, June 20, 2014

Geo 730: June 19, Day 535: Cut and Fill?

After looking more carefully at Tuesday's photo, I'm no longer convinced that this is Tyee... It *might* be Lookingglass Formation. The former is derived from either the Idaho Batholith or something similar nearby. Lookingglass is derived from erosion of the Klamath terranes. If this was Tyee, I'd expect a larger proportion of granite/granite-like clasts, and I'm just not seeing them. Add to that, I'm almost certain that our next stop, a winery, is on Lookingglass, so that may very well be what we're on here, too.

I'm not at all certain about this, but I think that on the left, about midway up the face, I'm seeing a cut-and-fill channel structure. It's also visible in yesterday's photo, in the right middle. That increases my confidence, but between the general fuzzing of the rockfall netting, as well as the poor definition of the beds, I'm not convinced enough to call it from 2+ years away.

Photo unmodified. March 9, 2012. FlashEarth location. (This is probably accurate to within 10-20 miles. Sorry, no clue.)

Geo 730: June 18, Day 534: Netting the Rock

Looking across the highway to the outcrop, you can see what looks like a vague haze over most of the outcrop. This is roughly the equivalent of hurricane fencing, and helps prevent smaller to moderate rockfalls from reaching the pavement. With larger falls, well, not so much. If you click through to that article, you can see that that outcrop, along the Sandy River near the Columbia River Gorge, had also been screened, but when the boulders are the size of trucks, the netting is just not strong enough to help.

Photo unmodified. March 9, 2012. FlashEarth location. (This is probably accurate to within 10-20 miles. Sorry, no clue.)

Tuesday, June 17, 2014

Geo 730: June 17, Day 533: Angular Conglomerate

The variability of grain size in this boulder is pretty awesome. A nice thing about coarse material like this is that you can really get a sense of the parent material. Sometimes, with sands, you can get sense under a microscope, but often, even then, it's frustrating. There's a granitic/dioritic clast near the center of the photo, which is what I'd suspect if we are in Tyee Formation. Tyee was formed when the drainage feeding this basin apparently captured a stream coming across the northern portion of the Rockies- in particular, its sediment was derived from erosion of the Idaho Batholith, or something similar and close-by, which might now be obscured by younger cover. Prior to Tyee deposition, this was a much more limited sedimentation area, the Lookingglass Formation, dominated by the much smaller Klamath Mountain area, and with a correspondingly higher proportion of low- to moderate-grade metamorphic rocks. Given the limited number of granitoid clasts in this boulder, I'm wondering if this might in fact be Lookingglass rather than Tyee.

Photo unmodified. March 9, 2012. FlashEarth location. (This is probably accurate to within 10-20 miles. Sorry, no clue.)

Monday, June 16, 2014

Geo 730: June 16, Day 532: Pebbly Sandstone

This is a fairly weathered surface, and I'm unable to identify most of the clasts other than quartz. It's a portion of the Tyee surrounding the coal of the last few days. In this view, it looks to be dominated by sand with a large, but still lesser, component of pebbles. The latter are clearly rounded, but are still angular enough that they don't look to have been transported too far. Tomorrow's shot, from the same boulder, is markedly different...

Photo unmodified. March 9, 2012. FlashEarth location. (This is probably accurate to within 10-20 miles. Sorry, no clue.)

Sunday, June 15, 2014

Geo 730: June 15, Day 531: Captivated by Coal

While Dana examined the coal fragment of the last couple days, I walked around to get a photo of her and the boulder. Once again, I was struck by how coarse-grained it was. It's also very poorly sorted, so it's not easy to get a sense of where the bedding planes were, but I'd be willing to bet that the long axis of the chunk of coal was laying flat upon it, and there does seem to be a suggestion of bedding roughly parallel to the shadows from the brush to the right.

By the way, I'm getting caught up from a day mostly off the web yesterday, and I'm not even going to try to get The Sunday Funnies up. I'll either do them tomorrow, or have a Double-Stuff Edition next Sunday. 

Photo unmodified. March 9, 2012. FlashEarth location. (This is probably accurate to within 10-20 miles. Sorry, no clue.)