Powell Butte is a cinder cone butte and is part of the Plio-Pleistocene Boring Lava Field, a group of volcanic cones that got their name from the low, forested Boring Hills formation. Located in the Portland Basin, the Boring Lava Field consists of monogenetic volcanic cones that appear as hills throughout the area, reaching heights of above their surroundings. The field includes more than 80 small volcanic edifices and lava flows in the Portland-Vancouver metropolitan area, with the possibility of more volcanic deposits buried under sedimentary rock layers. Volcanism in the Boring Lava Field is the product of subduction of the Juan de Fuca oceanic tectonic plate under the North American continental tectonic plate, as well as regional rifting. Powell Butte lies northwest of the Boring Hills, and the surrounding area includes (moving clockwise from the north) other volcanic centers like Green Mountain, Prune Hill, Chamberlain Hill, Devils Rest, Larch Mountain, Pepper Mountain, Kelly Butte, and Mount Tabor.