Olallie Butte is considered a shield volcano, though it has a conical shape that serves as a transitional morphology between steep, mafic volcanoes like Mount McLoughlin and Mount Thielsen and flatter, mafic shields. Made of basaltic andesite, it has a mafic composition. Nearby volcanic vents include the Sisi Butte, South Pinhead, and West Pinhead shield volcanoes and the Fort Butte, North Pinhead, and Potato Butte cinder cones. Cinder cones in the area have gray-red cinders that have been oxidized, scoria, agglomerate, and small lava flows consisting of porphyritic basaltic andesite and black and yellow-brown to dark yellow-orange, palagonite basaltic andesite. The black and orange color of some of the eruptive material from these cones suggests that there was interaction of the lava with wet ground or snow, causing rapid chilling of the ejecta that prevented oxidation from taking place. At Double Peaks and an unnamed hill southwest of View Lake, there are gray-pink to light brown-gray hornblende dacite lava domes.