Wednesday, June 10, 2020

Glacial Lake Missoula, Montana

We stopped in Missoula, Montana for a few days to see where the Glacial Lake Missoula formed over 10,000 years ago. We had previously explored central Washington in the Scablands, an area that was scoured by the floods that came through years ago...dozens, and even a hundred times.

Current city of Missoula showing ancient lake shorelines.

Lake Missoula water levels long ago covering the current city of Missoula.


There used to be 2,000-ft ice dam that was created during the last ice age.  This ice dam stopped up the Clark River and began to form Lake Missoula behind it.

3D rendering of one of the many ice dams that blocked the river

3D rendering of how the ice dam might've looked


It's estimated that it took between 50 and 100 years to fill up the lake ! The dam eventually gave way and all that water came rushing through at a rate of  65 mph!

This towering mass of water and ice literally shook the ground as it thundered toward the Pacific Ocean, stripping away hundreds of feet of soil and cutting deep canyons—”coulees”—into the underlying bedrock. With flood speeds approaching 65 miles per hour, the lake would have drained in as little as 48 hours.


Yes, I know...this is a bit geeky, but to us, it is totally fascinating.

 I hiked up to the floodplain lines on the mountain and this is what is what it looks like today looking towards the ice dam on the horizon. The water level would've been over 500 feet above me!
Lake Missoula stretched eastward more than 200 miles and, at its maximum height and extent, contained more than 500 cubic miles of water - more water than Lake Erie and Lake Ontario combined.

Path of the flood across central Washington

So...this is one of the great things about travelling so much. You learn many interesting facts and details about events and places. Plus, we get to be amateur geologists ! 

Hope you enjoyed this educational blog. More flowers and scenic views coming....

kim/steve/katie

oh, let's not forget our Katie-photo....

Katie likes to keep me company in the morning.
We started to post events on Twitter at @lastricks. If you have twitter, check it out.

https://twitter.com/lastricks



if anyone is interested in more flood data:

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