Quaternary stratigraphy and geomorphology of Northeastern Kodiak Island, Alaska

Kodiak Island archipelago has experienced multiple Quaternary glaciations that periodically covered the entire island, at times less a small refugium, under a regional ice cap. During glacial maxima, with relatively lower sea levels, large areas of the continental shelf were subaerially exposed as broad, low-relief plateaus between trunk glacier troughs. The continental shelf southeast of the islands was dissected by outlet glaciers draining the Kodiak Ice Cap uplands during the maximum extent of these glaciations. These trunk glaciers carved massive troughs into the shelf. Deglaciation after the last glacial maximum (LGM) occurred rapidly. By ~13.5 ka, ice had retreated to subaerially expose portions of modern Kodiak Island. Between ~13.5 ka and ~7 ka the average rate of deglacial isostatic uplift at Narrow Cape was ~17.5 m/ky, with initial rates reaching ~6 meters per century. Periglacial processes have been a significant long and short-term landscape shaping tool during interglacial periods, including the Holocene.