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Paleomagnetic Evidence For Northward Transport Of The Methow-Pasayten Belt, Julian L. (Julian Linus) Granirer

WWU Graduate School Collection

High level demagnetization isolates a single syntectonic magnetization in ten stable sites from the upper Cretaceous Winthrop and Midnight Peak Formations in the Methow-Pasayten belt of north central Washington. The mean direction of D=11.4°, 1=62.6°, Alpha₉₅=4.7° is discordant with the expected in-situ direction. This discordance is interpreted as resulting from 1,370 km of northward transport between 93 and 45 Ma. Correcting the contemporaneous Mount Stuart direction from within the Cascade terrane for approximately 16° of southward tilt brings it into accord with the new Methow direction. Further, if northward translation of these terranes were initiated by a southward …