Volcanic ash in surficial sediments of the Kodiak shelf — An indicator of sediment dispersal patterns

摘要: Abstract Surficial sediments of the Kodiak shelf, Gulf Alaska, contain various amounts volcanic ash whose physical properties indicate that it originated from 1912 Katmai eruption. The distribution is related to shelf physiography and represents redistribution by oceanic circulation rather than original depositional pattern event. can be used, in conjunction with grain sizes, as an indicator present-day sediment dispersal patterns on shelf. No significant modern input occurring which mostly covered Pleistocene glacial deposits. Coarse-grained flat portions shallow banks apparently are being winnowed, removed ash-rich fine material deposited depressions three four major troughs cut transversely across other trough seems experiencing a relatively high-energy current regime, little deposition material.