Saturday, December 27, 2014

Geo 730: December 27, Day 726: Dana's Ford

Dana doesn't drive a Ford, I don't think, but I'm not a car person, so I don't pay much attention to them, and really have no idea what kind of car she does drive. It has room for her, me and, often, a traveling companion. That's really all I need to know. But here, she's fording the small creek near Timberline Lodge. If it has a name, I don't know that either.

But for the last bit of outdoor geology before we head into look around the lodge proper (and yes, I'll twist myself into knots explaining how that's geology, too), let's take a look at the clasts in the creek. They tend toward large, but overall, they're poorly sorted. This suggests that the energy of the flow varies widely- which makes sense, given the climate and topography of this location. There's some rounding in the cobbles and boulders large enough to see well at this scale. This makes sense too- the larger clasts impact each other with more energy, rounding corners and edges rapidly, without much traveling distance. But overall, despite some rounding, they're pretty angular. This suggests we can't be too far from the water and sediment sources. The source snowfields of this creek are at most a few thousand feet, a kilometer, or so away. Now the point of this is not pedantry. The point is, if all you could see was the sediment in the creek- no horizon, no vegetation, no location- you could still infer much of the environmental setting, just from the nature and arrangement of the sediment itself. This is what geology is all about, and why it's so enthralling to me. We learn to notice the little clues, and think about them together in such a way as to paint a mental picture of the larger setting, which has often been long lost in the geological record. Here, though, we have the pleasure of the entire landscape available to inspect.

Photo unmodified. October 10, 2012. FlashEarth location.

Friday, December 26, 2014

Geo 730: December 26, Day 725: The Ford

As I mentioned on Christmas Eve, I was a little surprised at how much the stream- damp, but with no flow when we first crossed it- had swollen. It was by no means to the point where we were hesitant to cross, though we were definitely selective about where and how to do so. But there's little doubt that a misstep could have resulted in a wet foot or two. And since this was a day trip, I didn't have a change of socks or other clothes. Fortunately, there were no oopsies.

Photo unmodified. October 10, 2012. FlashEarth location.

Thursday, December 25, 2014

Geo 730: December 25, Day 724: Snow!

This isn't Christmas, but the snowiest event I can ever recall in Corvallis, last February 7th. Is this geology!? Yes, it is! I had intended to post a photo from Mount Bachelor with my family, six years ago, but just learned I don't have that folder on this computer. It's at home on the hard drive. Merry Christmas, all!

Photo unmodified. February 7, 2014. FlashEarth Location.

And to not break off from the tail end of our visit to Timberline, here's an unintentionally humorous warning that became very relevant just a couple weeks after I took the photo.
Photo unmodified. October 10, 2012. FlashEarth location.

Wednesday, December 24, 2014

Geo 730: December 24, Day 723: Brook

I've posted a couple of photos of the leading edge of this "diurnal stream," but I was quite surprised at how much it had swollen by the time it came to cross it again. This shot actually conceals just how much water is flowing, rather than illustrating it. After Christmas, I'll post a couple of others that get across the volume better.

Photo unmodified. October 10, 2012. FlashEarth location.

Tuesday, December 23, 2014

Geo 730: December 23, Day 722: A Final Shot

I have two very similar shots from this spot; the other is zoomed in more closely on the summit amphitheater and Crater Rock, showing more detail there. However, I like the framing of the trees more in this one. This was about as far up the path as we walked before turning around and heading back to the lodge.

Mount Hood is Oregon's tallest peak by quite a bit, at somewhere around 11,239 to 11,249 feet- recent measurements vary- and due to its proximity to, and visibility from, Portland, is probably the leading candidate for Oregon's "iconic" mountain. Crater Lake is likely more recognized, but this would be what most people picture with the phrase "Oregon Cascades." With that said, I'll reiterate that peaks like Hood, and yesterday's shot of Jefferson, are the exceptions rather than the rule for Cascades landscapes.

Photo unmodified. October 10, 2012. FlashEarth location.

Monday, December 22, 2014

Geo 730: December 22, Day 721: Jefferson Again

Looking a bit more directly south than the previous view down the valley on the left, Mount Jefferson sticks up through the smoke and haze from the numerous fires burning on the east side. While Hood is often mentioned as the most likely of Oregon's major Cascade peaks to erupt, Jefferson is among the least likely.

Photo unmodified. October 10, 2012. FlashEarth location.

Geo 730: December 21, Day 720: Looking Downstream

This photo makes it clear how steep the gradient of the Salmon River is on its way down Mount Hood, as well as how loose and rubbly the area being drained by it is. As I mentioned a couple days ago, this view should set alarm bells clanging for the geologically inclined. Anything on low ground near the river in this area is vulnerable to lahars. This high up the mountainside, it's in a significant canyon, so other than occasional trail wipeouts, there's not much to worry about. But this area could serve as a source for a debris flow that runs miles downstream to flatter ground, then fans out, dropping the rubble, and damaging or destroying pretty much everything in its path.

Photo unmodified. October 10, 2012. FlashEarth location.