Tuesday, October 30, 2007

Places of Interest

The class I TA for is learning all about the geologic history of Western North America this week. Much like Janice Dickenson, western North America has seen a lot of action in the past and now bears the scars of its wild ways. Here are a couple of places that I find especially interesting:

The Salton Sea:

The Sea itself is nothing more than a topographic low caused by the divergent plate motion which is ripping Baja away from the continent of North America. This man-made cesspool came to be in the early 1900s when water was diverted from the Colorado River whilst engineers were building an aqueduct intended to serve agriculture in the Imperial Valley. Its creation was an accident, but the sea became a popular tourist destination in the 1920s and 30s because it is hotter than shit out there in the desert. Water fowl also love the Salton Sea and the lake was stocked with fish like Tilapia. The problem with the Salton Sea is that there is no more freshwater input so as evaporation whisks away water, all the dissolved salts and chemicals stay behind and become more concentrated. The salinity of the Sea is upwards to 40 parts per thousand (ocean water has about 35 parts per thousand). Throw in some harmful algal species and a lot of dead fish and you have a tragically disgusting situation.

Yellowstone National Park:


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Yellowstone is a SUPERVOLCANO! Or Supaire Volcano. Yellowstone Park in northwestern Wyoming sits atop a large caldera that heaves and hoes up and down about 1.5 centimeters per year. This “breathing” in and out of the caldera makes me nervous, for one, but is indicative of what’s going on in the magma chamber below. As pressure increases and decreases, the land rises and falls. This will happen until the caldera explodes and obliterates everything from here to kingdom come. The good news is that eruptions are estimated to be several hundreds of thousands of years apart. We humans can blow ourselves up by then, thank you very much Yellowstone.

Willamette Valley, Oregon:



What’s so interesting about this little valley? Well, besides being a rich and bountiful place to grow agriculture, this valley was formed by the backlogging of water after the Great Missoula Floods. The Missoula Floods are floods of unimaginable proportion that roared across western North America at the end of the last glacial – about 18,000 years ago. Seriously, you can’t even imagine how crazy huge these floods were. So huge that the entire Willamette Valley served as a holding tank for water that was dumping into the Pacific Ocean via the Columbia River. Looking at the satellite image gives you some perspective of how much water that must have been. It was a lot. Like, a lot a lot.

See, places can be fun sometimes!

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