Geo 365: Sept. 28, Day 271: Caldera's Edge

Looking straight down from Sinnott Memorial Overlook, it's terrorizing to consider what we're looking at: the collapse of an entire mountain or multi-peak platform into an evacuated magma chamber. We're looking at the remains of an enormous eruption and subsequent failure of nearly 30 square miles of the High Cascades platform. It's roughly 1000 feet from the caldera rim down to the water, and the deepest parts of the lake are about 2000 feet below the waterline. In other words, we're seeing roughly a third of the total distance of the collapse. The ranger here said that underwater features of sufficient size are clearly visible to 200 feet. I can't vouch for that, but assuming he's correct, the fuzzy boundary where the talus fades out into Crater Lake's weird blue is at about 200 feet down.

Followup: @eruptionsblog adds: "Don't forget, the mountain extended above the current rim and the lake bottom has significant sediment and landslide fill." Good point. The "total distance" of collapse was certainly greater than what is preserved from today's rim to today's greatest depth.

Photo unmodified. August 18, 2011. FlashEarth location.

Geo 365: Sept. 27, Day 270: Phantom Ship

From Sinnott Memorial Overlook, Phantom Ship is right smack in the middle of the photo, below Dutton Cliff, and with Kerr Notch behind and to the left of it. Phantom Ship has long been thought to be the remains of a dike, but work a few years ago, linked in this post, seems to suggest it's a set of flows. (I don't know if or where that was ever formally published.) Dated at 400,000 years, it's now recognized as the oldest feature in the caldera.

Photo unmodified. August 18, 2011. FlashEarth location

Geo 365: Sept. 26, Day 269: Watchman and Hillman

From the left, The Watchman and Hillman Peak form the high points on the rim. "Devils Backbone" is the name given to the set of radial dikes on the right flank of Hillman Peak. Wizard Island, which I've learned is andesitic (I tend to assume cinder cones are basaltic), sits in the lake on the lower right, and the western end of Llao Rock rises on the far right portion of the rim.

Photo unmodified. August 18, 2011. FlashEarth location.

Geo 365: Sept. 25, Day 268: Llao Rock and Wizard Island

From the Rim Village, near Sinnot Memorial Overlook, Wizard Island sits close to the western caldera wall, and Llao Rock sits prominently in the wall behind it to the right. I've been told "Llao" is a Native American word for "eagle," but I'm not finding any corroboration for that online. It makes sense; the "wings" off of either side of the thickest part of the central flow are quite evocative of a soaring bird. However, "makes sense" is by no means the same as "correct." Just off the east (right) flank of Llao Rock, Mt. Thielsen makes yet another appearance.

Photo unmodified. August 18, 2011. FlashEarth location.

Geo 365: Sept. 24, Day 267: Up-Spine

Looking up the spine of The Cascade Mountains from the Crater Lake Rim Drive, Mt. Thielsen is on the right, Diamond Peak to the left and behind that. I don't know the names of the prominences in front of and to the left of Diamond, but we've climbed enough from the view of September 16 that the haze is distinctly less. The High Cascades is not as rugged as one might guess. Yes, there are some tall, pointy peaks, and glacial canyons are incised deeply and precipitously, but the High Cascade platform which dominates this view is really more of a gently rolling ridge overall than anything else.

Photo unmodified. August 18, 2011. FlashEarth location.

Geo 365: Sept. 23, Day 266: Dacite and Doug Fir

We're looking up at the sky here, not down at the lake... I had a brief moment of bemusement and amusement as I was going through to choose today's photo, and my mind tried to tell me the Douglas fir was growing horizontally from the caldera rim. To be honest, I'm not absolutely certain we're looking at either dacite or Douglas firs, though both are the most likely options. Dacite is intermediate between rhyolite and andesite, and is common on Mt. Mazama. The block to the lower left shows a nice conchoidal fracture. This was a random stop on the roadside, so I'm not precisely certain of the location; the link below is my best guess.

My, I'm doing a lot of guessing today, aren't I?

Photo unmodified. August 18, 2011. FlashEarth location.

Sunday Funnies: Student Edition

Oregon State is on a quarter system, unlike, it seems, most universities, which are on a semester system. The first day of classes is September 30, a week from tomorrow. As of yesterday, Corvallis has become noticeably more busy. By the middle of this week, I expect it'll be a zoo.

This one is mine, suggested by Adam Clark.

Also mine, in reaction to the first one.

This was suggested as a caption by a source I've lost; I just made it happen.

Matt Bors

The Gentleman's Armchair

"This is what happens when a car gets an allergic reaction." Funny to Me

Bits and Pieces

Funny to Me

Tastefully Offensive

I was going to caption this "free-range red blood cell." But I didn't. Blackadder

9 Gag... "It actually did work."

"And the gap keeps getting bigger." Liz Donnelly, at The Nib

Blackadder

Are You Talking to Meme?

Lawyers, Guns and Money

Fake Science

Bits and Pieces

Text From Dog

Dr. Boli

Are You Talking to Meme?

Blackadder

Funny to Me

"How the Sex Education Section in Class Goes:"

Bits and Pieces

Safely Endangered

Bots... Wil Wheaton's Tumblr

Spud Comics

Very Demotivational

Funny to Me

Tastefully Offensive

Doghouse Diaries

Savage Chickens

Funny to Me

You mean, Obama twerks, too!? Tastefully Offensive

Bits and Pieces

Bits and Pieces

Surviving the World

Blackadder

What Would Jack Do?

Chainsawsuit

Bits and Pieces

Funny to Me

Extrafabulouscomics

Via Blackadder (Gary Larson, The Far Side)