Blue Skies in Alaska

Blue Skies in Alaska

Submitted by John Garver (Union College)

Part of the 2018 Keck Alaska project is focused on understanding the tectonic evolution of the Upper Cretaceous Valdez Group in Prince William Sound, which is part of the Chugach terrane. This unit is typically viewed as a Mesozoic-Tertiary accretionary complex that is well exposed for ~2200 km in southern Alaska and is inferred to be one of the thickest accretionary complexes in the world. The Chugach flysch is mainly comprised of younger deep-water turbidites with sparse fossil localities that indicate Campanian to Maastrichtian deposition. Work this year by Nicholas Gross Almonte (Carleton College) will focus on using U/Pb dating of detrital zircon to better understand that age of deposition and provenance of this important unit in southern Alaska.