Glacially influenced submarine-channel sedimentation in the Yakataga Formation, Middleton Island, Alaska

The Yakataga Formation (Miocene to Recent) is a 5-km sequence of marine and glaciomarine sediments underlying a large area of the Gulf of Alaska continental shelf. The upper, early Pleistocene part of the formation, some 1.25 km thick, is exposed on Middleton Island. A 200-m-thick sequence of channelized sand and gravel lithofacies at the base of the exposed succession outcrops on extensive wave-cut platforms. These facies fill channels up to …