Paleomagnetic and geochemical analysis of the Summit Creek volcanics, South-Central Cascades, WA

The Basalt of Summit Creek is an enigmatic basalt unit that is about 55 million years (Ma) in age, located south of Mount Rainier. These basalts formed in a transitional time between the formation of the Coastal Range Basalts and the present Cascade arc. Through geochemical and paleomagnetic techniques, samples were collected and analyzed. Paleomagnetic samples showed nearly complete post eruptive demagnetization. Geochemical samples show arc type rocks lower in section and OIB at upper sites. Goals and Purpose (1) To determine the tectonic setting in which these rocks formed (2) To better understand their relationship to the Crescent Basalts (3) To establish the extent to which these basalts have undergone rotation and/or northward translation. Acknowledgements I would like to thank: 1) The University of Puget Sound for funding my Summer Research Grant, 2) Professor Mike Valentine for guiding me through this process as well as sharing his knowledge of paleomagnetism, 3) Professor Jeff Tepper for is assistance in identifying rocks, fusing and ICP analysis.