Geology Reference
In-Depth Information
The small playas and pluvial lakes that dot southeast Oregon today are all that remain of much larger
bodies of water here during the Ice Ages (after Allison, 1982).
masses. The highest part of Steens Mountain has been
Kiger Gorge, the canyon of Little Blitzen River, Big
more thoroughly dissected by erosion, much of it
Indian Creek, Little Indian Creek, Wildhorse Creek,
glacial, than other scarps in southeastern Oregon. This
and Little Wildhorse Creek were all gouged out by
is due to steeper gradients and the greater precipitation
valley glaciers which filled the streambeds. Fish Lake
that accompanies higher altitudes. Glaciation on the
occupies a shallow depression where Fish Creek was
western slope of the Steens sculpted lake basins and
dammed by a glacial moraine. Other lakes, such as
cut deep U-shaped valleys. The symmetrically curved
Wildhorse Lake, occupy glacially cut, saucer-shaped
valleys.
Ducks, pelicans, herons,
and cormorants used
Fossil Lake as a stop-
over during the Plesitocene.
