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Missoula Floods!
Mar. 9th, 2017 11:52 pmTonight we went to Science Pub to hear about the Missoula Floods, which I'd learned about from a PBS science show years ago. Back in prehistoric times, there was a series of huge floods when the ice dam of a glacial lake in Montana broke, some 89 times over 3000 years or so. These floods scoured all the soil out of much of eastern Washington and washed it downstream, with quite a bit of it ending up here in the Willamette Valley, and much more of it being washed out to sea. The whole Willamette Valley was flooded to an elevation of 400', from Portland to the part of Eugene downtown and north of it. We would have been a mile or so from a huge lake!
Were people affected? Possibly. The most recent flood was 15,000 years ago, and we know that humans were living in Oregon 14,000 years ago.
Today, ironically, people have to plant their vineyards in Oregon's hills rather than the valley, because the valley soil is much too fertile, thanks to the floods. In Washington state, though, they have to stress their grapes by withholding irrigation, because their poor soil is just right.
I bought the speaker's book. I confess that my interest in geology is limited to things that are pretty and things that are dramatic, but my home state is full of geological drama.
Were people affected? Possibly. The most recent flood was 15,000 years ago, and we know that humans were living in Oregon 14,000 years ago.
Today, ironically, people have to plant their vineyards in Oregon's hills rather than the valley, because the valley soil is much too fertile, thanks to the floods. In Washington state, though, they have to stress their grapes by withholding irrigation, because their poor soil is just right.
I bought the speaker's book. I confess that my interest in geology is limited to things that are pretty and things that are dramatic, but my home state is full of geological drama.