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Reconnaissance mapping of 21 glaciated valleys in the Elkhorn Mountains of northeastern Oregon revealed limits and relative ages for two alpine glacial events. Evidence for possible Pinedale (10,000-30,000 years ago) and Bull Lake (150,000-200,000 years ago) glaciations was observed. Old (Bull Lake?) drift is characterized by orange grus-rich soils, rotten granitic clasts at a depth of 1 to 2 meters, and, where present, basalt clasts with significant weathering rinds. These areas which were glaciated by Bull Lake ice exhibit bedrock tors which rise about 1-2 m above the ground surface. These tors have had time to develop from the end of the Bull Lake glaciation because they have not been eroded by Pinedale ice. Late Pleistocene (Pinedale?) drift is characterized by grayish tan sandy soils with fresh clasts. Some areas covered by Pinedale ice exhibit scoured bedrock surfaces. Tors in nearby unglaciated areas …