Sunday, October 3, 2010

Columbia River Basalt Columns

Much as the heyday of the columnar jointing meme seems to be past, I’d like to jump on the bandwagon in support of Washington’s columns as championed on Northwest Geology Field Trips.

Washington is home to what I would argue is some of the raddest columnar jointing around, as it’s easily reached and highly extensive. And by “highly extensive",” I mean Spans-63,000-Square-Miles extensive.

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These columns (near Grand Coulee, WA) show an unevacuated lava tube.* The arch of columns would have been the tube’s roof, as those cooled and cracked perpendicularly to the cooling surface (the air.) Underneath this is a layer of lava that cooled in the tube, and beneath that are more columns from the bottom of the flow. Above this tube is the middle section (the entablature) that cooled in a different fashion and thus has some pretty fugly hackly jointing.

 

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Dry Falls, whose walls are composed of columns. You just can’t tell that because it’s so stinkin’ huge from this vantage point.

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These columns are the Ellensburg formation, and this exposure is over near Naches, WA.

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This is Frenchman Coulee, and is once again composed of columns too distant to see.

P1170467But here they from a closer viewpoint – in addition to the columnar joints, you can see horizontal weak areas perpendicular to cooling along the column’s side.**

Oh, and you know what else Washington has that’s better than anywhere else?

Plaid-clad junkies who don’t shower.***

My advice: visit the Columbia River flood basalts, but avoid Aberdeen after dark.

 

*At least, that is what an unevacuated lava tube has been pointed out to me as. As always, I could be really incorrect.

**I think.

***I really like plaid.

2 comments:

Gaelyn said...

I've always liked the columnar basalts in WA. In fact much better than Nirvana. ;) You are getting around this summer. How long will you be on this job? I'm done in two weeks. Where did this summer go?

helena.heliotrope said...

Yeah, Nirvana's never been my favorite. Just too depressing.
I'm just going to be in Washington for a month. After that, mum and I are headed down to ORCA until December to finish that project. Three states in six months, woo!
Where are you going to be headed after you're done?