HR: 0800h
AN: H41B-0297    [Abstracts]
TI: A Simple Expedient Method for Interpreting the Landscape With Digital Imagery Tools: The Secret Srings Landslide as an Example
AU: * Hicks, B
EM: GEOREGON@aol.com
AF: Geo-Oregon, LLC, 190 Vista, Ashland, OR 97520 United States
AU: de la Fuente, J A
EM: jdelafuente@fs.fed.us
AF: USDA Forest Service Klamath National Forest, 1312 Fairlane Road, Yreka, CA 96097 United States
AB: The volcanic borderland between California and Oregon is a remote, pristine area, with limited geologic/environmental information available. This landscape is dominated by the 300-500 m Klamath River gorge, which is incised through Cascade volcanic rocks. Weak pyroclastic rocks exposed in the gorge facilitated the development of massive landslides, the largest of which is the Secret Spring Landslide (Williams 1949), (Hammond 1983), (US Forest Service 1983, 1996), (Hazlett, et al, 1997). It is 2- 4 km wide, 5 km long, and located south of the river, about 11 km upstream from Copco Reservoir. Three dimensional images (from 30 m DEM's) viewed on a monitor screen were used to stratify the landscape around the landslide in an iterative, intuitive process, as follows: a) Observe feature in an image; b) Inspect feature on air photos (stereoscopically) and in the field; c) Examine image again, modifying viewing parameters (scale, relief, sun angle, tilt, etc.) and make new interpretations. This process allows discrimination and delineation of various terrains, e.g., talus slopes., glacial features, landslide scarps, more active to less active landslides, fractures, faults, lineations, evidence of river blockage, abandoned stream channels, etc. Manipulation of viewing parameters is critical for interpretation. Modifying the parameters challenges the interpreter to reexamine the processes involved in shaping the terrain. Focusing on the regional view allows integration of innumerable details of the terrain to define each local view. For the digital imagery work "Hawkeye" digital software developed by M. Vannier was used, (copyright) 18 Software, Portland, OR (18software.com).
DE: 1815 Erosion and sedimentation
DE: 1824 Geomorphology (1625)
DE: 1894 Instruments and techniques
DE: 1625 Geomorphology and weathering (1824, 1886)
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting