Siletz River Volcanics
| Siletz River Volcanics | |
|---|---|
| Stratigraphic range: Selandian-Ypresian (Tiffanian-Bridgerian) | |
Exposed pillow lava in the Northern range | |
| Type | Formation |
| Underlies | Yamhill Formation |
| Lithology | |
| Primary | Sills of tholeitic to alkalic basalts |
| Other | Tuff breccia, siltstone, sandstone |
| Location | |
| Coordinates | 44°54′N 123°24′W / 44.9°N 123.4°W |
| Approximate paleocoordinates | 47°00′N 107°30′W / 47.0°N 107.5°W |
| Region | Benton, Coos, Douglas, Lane, Lincoln, Polk, Tillamook, Washington & Yamhill Counties, Oregon |
| Country | United States |
| Type section | |
| Named for | Siletz River |
The Siletz River Volcanics, located in the Oregon Coast Range, United States, are a sequence of basaltic pillow lavas that make up part of Siletzia. The basaltic pillow lavas originally came from submarine volcanoes that existed during the Eocene.