Numerous investigations demonstrate that mantle convective processes such as upwelling affect the surface topography of the overriding plate. The surface expression of mantle flow has been coined ‘transient topography’. Transient topography in the North American plate is thought to result from a mantle thermal anomaly beneath the Yellowstone volcanic center,...
The basaltic landscapes of the Oregon High Cascades form a natural laboratory for examining how geologic setting and history influence groundwater flowpaths, streamflow sensitivity to climate, and landscape evolution. In the High Cascades, highly permeable young basaltic lavas form extensive aquifers. These aquifers are the dominant sources of summer streamflow...
Various types of mass movement features are found in the drainage
basin of the East Fork Coquille River in the southern Oregon Coast
Range. The distribution and forms of mass movement features in the area
are related to geologic factors and the resultant topography.
The Jurassic Otter Point Formation, a...
Twelve stream segments in the Silvies River drainage system were classified in
the fall of 1993 and again in 1994, using a morphological classification of natural
rivers (Rosgen 1994). Bankfull flow of stream channels is the key feature of this
system. Measurement of bankfull is used in the calculation of...
Landforms sculpted by mass movements comprise much of the landscape in the Middle Santiam study area. Bedrock in the area is
mostly basalt and andesite flows and varied volcaniclastic rocks of the Little Butte Volcanic Series of Oligocene and early Miocene age, unconforniably overlain by andesite flows and tuffs of...