Fatal Rock Slides

If you live anywhere where there's mountains or significant road cuts, you've no doubt seen signs warning of falling rocks. This past weekend, and again last night, rocks the size of automobiles crashed onto the major interstate just 20 miles from our house -- a road I've driven numerous times. Actually, come to think of it, the rock slides took place very close to where I snapped the photo featured in last week's Photo Friday.

The sad part of this story is that despite the first slide taking place at 1am, three women just happened to be travelling by at the exact moment the slide took place and were crushed to death. They were returning home from a concert in eastern Washington.

Seattle Times: The collapse began about 5 or 10 feet up the cliff, above a 30-foot-wide ditch designed to catch falling rock. A chunk of granite about 60 feet high, 20 feet wide and 10 feet thick shattered, sending about 300 cubic yards of rock — the equivalent of 30 dump-truck loads — into the ditch and onto the shoulder and all three westbound lanes, a distance of about 70 feet.

Despite teams of geologists being sent to the scene to investigate nearby areas for potential slides, another one occured less than 48 hours later, and less than a mile away. This second one, like the first, was at a spot deemed safe by the geologists. The scary part of this story isn't that this could happen -- we all know it could -- but that the state's transportation department has reported that they receive 13 million dollars a year to investigate and armor against potential slides and that there are over 100 areas in Washington state deemed more likely to fall than the one that took the lives of three women this weekend. They reportedly have over 100 million dollars worth of slope stabilization work to do.

One of the first things you learn as a geologist in the US is that there is a huge difference between the east and the west coasts. The east coast has experienced hundreds of millions of years of weathering and, by and large, most "catastrophic" change has already occured. The environment is dormant, for lack of a better word. Out west, where the landscape is far younger, geologic change is constantly happening all around you. And like a hurricane or tsunami, it can't be stopped. And for one reason: water. One can no sooner hold back the sea than we can keep water from eroding a mountainside. And just as people will always yearn to live near the ocean, so will we need and want to travel through the mountains. This weekend's rock slides are just a reminder of another thing we need to worry about. As if we didn't have enough already.

Photo by Seattle Times: http://tinyurl.com/8pnex
Story by Seattle Times: http://tinyurl.com/8zdn8

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