The movement characteristics of five landslides are
compared and interpreted based on records of approximately
10-years duration. Condon landslide in the Oregon Coast
Range has consistently exhibited brief (1 - 8 days) movement
episodes in wet winter months, separated by long periods of
no movement. The translatory movement is probably...
Timber management of coastal watersheds in southwest Oregon has
been complicated by the need to protect anadromous fish habitat from
accelerated stream sedimentation resulting from management activity.
The rugged terrain of the Elk and Sixes River basins is underlain by
the complex geological province of the Klamath Mountains, in which...
The Lookout Creek Earthflow is located in the Cascade Mountain
Range in western Oregon. The Cascade Mountains are mainly volcanic
in origin, and deposits in and around the slide have a complex geomorphic
history,, affected by glacial, mass movement, and fluvial
processes. The currently moving land mass is about 1600...
Rapid, shallow soil mass movements (landslides) are examined for a 6,000 ha managed forest area in the Oregon Western Cascades. Analysis of landslide occurrence considers the physical characteristics and frequency, the influence of clearcutting and road construction, and some resource impacts. Nonparametric statistical methods
are employed to test the significance...
A landslide inventory, statistical analyses and a Geographic Information System (GIS) are used to analyze landslide sites and potentially unstable terrain in the Oregon Coast Range. The objectives are to evaluate the efficacy of locating landslide sites with topographic variables and discriminate the difference between sites where landslides have and...
A study conducted along the Lincoln County, Oregon coast delineated the exact location of 153 landslides. The landslides were found through the interpretation of aerial photographs. Each landslide was verified in the field and its class (ancient, historic, recent), type (slump, debris slide or flow, planar slide),, and status (stable,...
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...
Landslides are ubiquitous within the state of Oregon, imposing an annual estimated cost of more than $10 million. Weak, saturated soils at steep slopes combined with persistent rainfall throughout most of the year provide a dangerous environment for this natural disaster, particularly in western Oregon. This grim situation is intensified...
Landslides are a pervasive hazard that can result in substantial damage to properties and loss of life throughout the world. To understand the nature and scope of the hazard, landslide hazard mapping has been an area of intense research by identifying areas most susceptible to landslides in order to mitigate...
Average annual losses caused by geologic hazards in Oregon are difficult to determine, owing to incomplete and scattered data. Preliminary considerations, however, indicate that losses to landslides may total between $4 million and $40 million per year. As many as nine persons have been killed by one landslide in Oregon...
Precipitation data from 1988-1995 for 13 rain gauges of the Department of Forest
Engineering rain gauge network, and a longer precipitation record, 1976-1995, at Mapleton were analyzed. The objectives were to assess the spatial and temporal distribution of precipitation intensity and antecedent precipitation, and understand the role of these characteristics...
A simple debris-slide model, employing a digital elevation model (DEM) and geological data, was used in a geographic information system (GIS) to map slope stability in the Andrews Experimental Forest, located in the western Cascade Range in Oregon, USA. To evaluate the contribution of error in elevation to the uncertainty...
Esmond Creek is a tributary to the Siuslaw River located in the Oregon Coast Range. It is 18 km in length and drains a watershed area is 48.9 km². Average channel gradient of the study reach is 0.9%. In 1988 a landslide
occurred in the Esmond Creek watershed involving approximately...