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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Holocene Channel Changes of Camp Creek: An Arroyo in Eastern Oregon

Welcher, Karin Else 06 1900 (has links)
155 pages / In the stratigraphic record of Camp Creek are episodes of fluvial scour and fill thousands of years old. Radiocarbon dates and the Mazama tephra, which serves as a stratigraphic time line, temporally bracket episodes of vertical aggradation and incision. Before 9000 years B.P. the valley floor was scoured to the Tertiary bedrock. Aggradation dominated since that time. Large cut-and-fill structures indicate that two periods of erosion occurred prior to incision of the modern arroyo. The first occurred before 6800 yr B.P. and the second occurred approximately 3000 years ago. The modern arroyo-channel flows at or near the Tertiary bedrock, is entrenched as much as nine meters in the valley-fill alluvium and is thought to have originated during the late 19th century.

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