Lacustrine Sediment Record of Multiple Quaternary Lava Dams on the Owyhee River, Southeastern Oregon

<p>Multiple lava dams and correlating lakes impacted the Quaternary evolution of the Owyhee River. Sediment records from lava-dammed lakes were investigated to understand effects of the West Crater (WC) lava dam (~70 ka), the Saddle Butte 2 lava dam (~144 ka), and the Bogus Rim lava dam (~1.9 Ma). Evidence from the WC lava dam and related features indicates that dam duration consisted of five stages (1) dam and lake formation at ~70 ka; (2) dam overflow and lake sedimentation from ~70–46 ka; (3) removal of lava dam and lake termination from ~46 ka to at least 36 ka; (4) incision of underlying units from ~36–15 ka; and (5) incision to modern river level from ~15–0 ka. The WC lava dam lasted ~24,000 yrs and ~31,000 yrs of incision was needed to reestablish the river. This information gives perspective on the effects of lava dams on fluvial landscapes.</p>

Name thesis:degree_name

Master of Science (MS)

Discipline thesis:degree_discipline

Geological Sciences

Year dc:date.available

2010

Author dc:creator

• Orem, Caitlin Anne

Contributors dc:contributor

• Lisa Ely
• Beth Pratt-Sitaula
• Marie Ferland

• lacustrine
• sediment
• lava dams
• Owyhee River
• oregon
• Geology
• Geomorphology
• Hydrology
• Sedimentology
• Volcanology

Repository record dc:identifier

https://digitalcommons.cwu.edu/etd/1459

OAI identifier oai:identifier

oai:digitalcommons.cwu.edu:etd-2484