Camped In An Earthquake Zone?

We have been enjoying the fish camp that we are using to explore the Yellowstone area.  The fisherman have been very friendly to us including the Actor, William Devane, who let us short cut across his campsite when we were walking from the river back to our motor home.  He apparently is an avid fly fisherman and keeps a fifth wheel at this campground.

 

The extra miles into Yellowstone haven’t really been an issue as it is a beautiful drive east through the Madison River Canyon and past two reservoirs on the river.  But as you drive along, you see these roadside markers:  “Night of Terror”, “Refuge Point”, “The Lake That Tilted”, “Earthquake Lake”, etc.  So we had to investigate a bit.  Seems this area is one of the most infamous geologic areas of the US in the 20th century.  In August of 1959, a 7.5 magnitude earthquake hit this area.  That was the strongest quake ever recorded in the Rocky Mountain Range.  The quake was so severe that the bed of one side of Hebgen Lake fell nearly 20 feet causing the Lake to “tilt” during the earthquake.  But far worse was the massive and horrific landslide of one of the faces of the mountains of the canyon.  It is estimated that 6.8 million equivalent dump trucks worth of material fell off the side of the mountain, across the river valley, and back up the side of the mountain on the other side of canyon.  Shown below is part of the mountain face that crumbled.  The second picture shows a giant boulder, one of many, that rode across the top of this “river” of rocks to the other side of the canyon.

There was a campground right in the area of the rock slide.  Nineteen people were tragically buried under the rock.  Another nine people elsewhere in the quake zone were killed.  The roads leading into and through the area were destroyed.  Some 250 people were trapped in the canyon.  The earth slide across the canyon created a new dam downstream of the dam for Hebgen Lake.  The water behind this newly created dam rose rapidly.  The people trapped in the canyon had so seek high ground, now know as Refuge Point from which the injured were evacuated by helicopter.

The water behind the new dam was backing up to the Hebgen Lake Dam threatening its integrity and thereby risking a massive flood downstream of the two dams.  The Army Corp of Engineers had to come in quickly and dig a channel through the center of the dam created by the rock slide to lower the lake behind it.  There is still a substantial lake behind this dam, known as Earthquake Lake.  Dead trees still stand in the Lake and are known today as ghost trees.  And it is an eerie site, especially with ugly back Cormorant birds perched in the ghost trees.

So where are we camped in relation to all this?  We are at just about the last bend in the river that you can see in the picture to the right.  That is about two miles downstream from the rock slide dam of Earthquake Lake with the dam and Hebgen Lake setting right upstream of Earthquake Lake.  The thought has crossed our minds more than once while here about what another quake of this magnitude could mean to us with a steep mountain face on at least one side of us here at the camp and with all that dammed up water upstream from us in the canyon.