Trench-fill submarine-fan facies associations of the Upper Cretaceous Chugach terrane, southern Alaska

T. H. Nilsen

doi:10.1007/bf02462465

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Trench-fill submarine-fan facies associations of the Upper Cretaceous Chugach terrane, southern Alaska

T. H. Nilsen

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Abstract

Turbidites of the Upper Cretaceous Chugach terrane of southern Alaska were deposited in a trench during northward-directed subduction. The fault-bounded outcrop belt of the Chugach terrane is about 2000-km long and 100-km wide and was accreted to Alaska during the Cenozoic. Turbidites are at least 5000 m thick, are extensively deformed, have been regionally metamorphosed, and have been intruded by anatectic granites. Facies associations indicate an east-to-west progression from inner-fan to middle-fan, outer-fan, fan-fringe, and basin-plain deposits. To the north is a marginal trench-slope facies association and a basin. ?? 1984 Springer-Verlag New York Inc.

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T. H. Nilsen. 1984. Trench-fill submarine-fan facies associations of the Upper Cretaceous Chugach terrane, southern Alaska. https://doi.org/10.1007/bf02462465

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