Record Details
Morphometric analysis of landslides and slope stability on the north shore of the John Day Reservoir, Columbia River, Oregon and Washington
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Morphometric analysis of landslides and slope stability on the north shore of the John Day Reservoir, Columbia River, Oregon and Washington |
| Names |
Woelke, Franziska
(creator) Rosenfeld, Charles L. (advisor) |
| Date Issued | 1996-11-26 (iso8601) |
| Note | Graduation date: 1997 |
| Abstract | The John Day Reservoir, a large reservoir between the John Day and the McNary Dams on the Columbia River, must be lowered several feet below design level during salmon migration season in order to preserve anadromous fish habitat. This research assessed the north shore of the John Day Reservoir for current slope stability and landslide reactivation potential. Ancient landslides of immense dimensions are located on the northern shore of the reservoir. These paleoslides and the bedrock paralleling the slopes on the northern shore may support new sliding activity. Fluctuating water levels may cause slope instability and erosion due to the absence of shore protecting vegetation in the fluctuation zone and due to the lubrication and fluctuating buoyancy of the toes of these landslides. Lowering the water level might reactivate landsliding activity, which can have adverse effects on transportation routes on the north shore of the John Day Reservoir, including Highway 14 and the Burlington Northern Railroad. The northern shore of the John Day Pool is very steep and highly susceptible to mass failures. Forty-six mass failures were delineated on the northern shore. Forty-one of these could be analyzed statistically. Rotational Slides and Viscous Flows were the major two process groups delineated. The morphometric analysis of mass movements developed by Crozier (1973) was utilized for the slide assessment. The applicability of this analysis was limited by the large dimensions of the mass movements in the study area. This research has shown that a moderate risk of increased mass wasting activity may result because of proposed pool elevation changes at several sites along the northern shore of the John Day Reservoir. |
| Genre | Thesis |
| Topic | Landslides -- Oregon -- Umatilla, Lake (Or. and Wash.) |
| Identifier | http://hdl.handle.net/1957/9860 |
