Sunday, September 4, 2011

Sunday Photo(s)

The area around Mt. Mazama, Oregon, better known as Crater Lake National Park is a fascinating one for anyone who is even mildly interested in the geological history of the Pacific Northwest. In the not-too distant past, this area was the site of awesome geological happenings.

This is the north entrance to the park. Note all the trees around it. This entrance is about seven miles (11 km) from the crater.

Image credit: All images by Cujo359

One of the first stops for us along the way was the Pumice Desert. This is the vista there. Remember that this is only a few miles from the park's entrance, where there are lots of trees:

What happened to the trees? Let's read the sign, shall we?

Lockwood, our geological spirit guide, told me that he also thought that the soil was having some trouble retaining water, thanks to all the pumice. In any event, we're still quite a few years away from having a forest here.

How did all that pumice, as well as a somewhat heavier volcanic rock called scoria, get there?

Not all the stones were small ones. This bit of pumice was a few feet from the road. Despite its size, it was light enough to tip easily.

It turns out there was a sign that explained that, too. Around 7,700 years ago, this area was an extremely active volcano. It poured out all sorts of rocks for a few centuries, before things really went sideways. But I'm getting ahead of myself.

Go toward the rim, and then halfway around it, then continue south, and you eventually reach an area called The Pinnacles:

As the sign says, about the same time all that pumice and scoria was being tossed onto the north side of the volcano, these little spikes of magma, called fumaroles, were being formed to the south. In the intervening 7,500 years or so, the river washed away the volcanic debris that was covering them, leaving them exposed.

Here's a zoomed shot of one fumarole, showing that these columns were created from a lot of heat.

They're also on both sides of the river. No, these aren't tree stumps:

It's hard to get a sense of scale here, but some of these towers are over ten feet (3 meters) tall.

Some even look a bit like smokestacks, which is essentially what they were:

Follow along the trail, and you can see quite a number of these towers of volcanic rock. At the end of the trail is a different kind of tower:

It appears to be a stone tower that was once used to mark the edge of the park. So, we'll head back toward the crater, and see that next week.

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