Monday, April 14, 2008

Gravity, rocks, mud, and the Big Snow Year

Headline of the week, from my local paper: Geologic forces plague East Animas Road.

Ten years ago, a big piece of Dakota Sandstone fell off the cliff on the top of the ridge north of town. For years, we would wave our arms at it, and tell stories about it to intro students. And then, in the fall of 2006, mud started to trickle out of the bottom of the rock fall. It had been a wet fall, and the finer grains were remobilizing into a debris flow.



One of out students did a senior thesis on the hazard. Usually when students predict something in geology courses, they don't see their predictions come true. Not so with this student.

When the snow melted this year, the mud came down with it.



East Animas Road has been closed for the past few weeks. I drove out there one afternoon to take pictures. Apparently there have been multiple feet of mud across the road at various times. There's a loader parked there, and it moves the mud out of the way, and then more comes down. Fortunately, there are no houses in the direct path, and the road has two outlets, so it's an inconvenience rather than a tragedy.

The mud is really slippery, too.

(And field camps who want to know where this is - e-mail me and I can give directions, and let you know if it's still running. The snow has nearly melted from that part of the ridge, so the mudflows may be done... for this year.)

4 comments:

ScienceWoman said...

This is why earth surface processes are so much cooler than those deep earth things. You can actually see them in action.

/personal bias

Kim said...

:P

Seamonkey said...

oh how I agree.....but maybe I am slightly biased too

Geology Happens said...

Back in the day (1978-1980)I lived just off of East Animas north of Trimble and remember the flooded fields from spring runoff...of course now those fields are full of homes.