Dredged Trachyte and Basalt from Kodiak Seamount and the Adjacent Aleutian Trench, Alaska

Blocky fragments of aegirine-augite trachyte (with accompanying icerafted gravels) were recovered from the upper slopes of Kodiak Seamount in several dredge hauls. An alkali basalt pillow segment was also dredged from a moatlike depression, at a depth of 5000 meters, near the west base of the seamount. These retrievals confirm the volcanic origin of Kodiak Seamount and further support the view of Engel, Engel, and Havens that the higher elevations of seamounts are composed of alkali basalts or related variants.