A History of STRUM
by Roy Matson
A Bit of Geology

We in the Beef River Valley live in the so called driftless area, the part of Wisconsin
untouched by several glacial advances, the last of which remade the face of this state some
10,000 years ago. These masses of snow turned to ice, formed somewhere above Hudson
Bay. With proper temperatures and climate prevailing for thousands of years, continual
heavy snows resulted in an ice buildup that scientists estimate to have been nearly two
miles thick. The immense weight caused a movement outward and as additional snow and
ice built up this outward action continued, leveling and carrying everything in its path. 

Snow now covers about 10% of the earth’s surface.  Scientists estimate that cover during
the glacial age was about 30%, and so much water was ice that the oceans were about 330
feet lower than today.  The earth’s water today is agreed to be about 97% ocean water,
2% ice and 1% river, lake, creek and underground supply.  Release of the water held in ice
caps at this time would raise sea levels 180 to 200 feet.

There were four such advances that touched our state during various ice ages, all in forms
of tongues that moved in several directions. The time required for the build-up, total
movement and melting of such a tongue of 10,000 feet thickness or more is supposed to
be around 130,000 years.

How is all this known? This tremendous weight carried rock, stone and silt as the glacier
was forced to move. Then it left scratches on bed rock, formed deposits of earth in forms
that marked direction and tore up beds of hard material and left parts of these beds
hundreds of miles from the original site. The only spot in our state left untouched was the
driftless area of which our river valley is part of the northern boundary.  This area

CLICK for Map of Beef River: Original and Present Course (may be slow to load)