Rock Slide

Rock Slide

One of my favorite phrases is Pyroclastic Flow; it just rolls off the tongue.  It's a fast moving current of superheated gas and rock.  It's what comes out of the ground when volcanoes explode like Mount Saint Helens on May 18, 1980 or what buried Pompeii in AD 79.  What's left over after one of these eruptions is a large amount of rock, ash and other debris.  Evidence of pyroclastic flows and volcanic eruptions is evident around Mount Rainer.

Mount Rainier is an active volcano, last erupting in 1894.  As we walked this segment of the Wonderland Trail, the soil is basically volcanic ash.  Somewhere between the consistency of sand and dust, this material is everywhere and in large amounts.  When an entire hillside is made of the remains of a pyroclastic flow, it is not very stable. 

Just before Martha Falls on the Wonderland Trail, there is a rock slide where the remains of a pyroclastic flow is still moving.  This rock slide was identified by the park service and temporarily repaired by the trail crews, but it is obvious when you're on it that it is not stable.  It is not dangerous, per se, but anyone trying to run up a sand dune will tell you that at times you just find yourself at the bottom.  Just stay on the trail and don't linger. 

It is obvious that this section of the trail will be washed out again this winter if no other work is done to stabilize or reroute the trail.  However, it may not be possible given the current route to stabilize the trail.  A large bridge structure just west of the rock slide was destroyed recently.  Evidence of multiple rock slides were apparent along this segment of the trail.