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Paleomagnetism And Tectonics Of The Crescent Formation Northern Olympic Mountains, Washington, Andrew C. (Andrew Clyde) Warnock

WWU Graduate School Collection

Use of a small-diameter core drill has allowed the paleomagnetic sampling of the rims of fractured pillow basalts of the lower Crescent Formation in the northern Olympic Mountains. The pillows selected have spherical or oblate morphologies which typically develop on horizontal or mildly-dipping surfaces. Pillow keel structures and sedimentary interbeds were used to obtain bedding attitudes and top directions for use in structural corrections. All specimens were subjected to progressive thermal demagnetization. After removal of a low blocking-temperature recent overprint, stable endpoints were reached by 580°C in 11 of the 33 sites sampled (large within-site scatter was commonly observed in …