South Cascades Arc Volcanism, California and Southern Oregon Red Bluff to Redding, California, July 20 - 26 1989 - Muffler, L. J. Patrick; Bacon, Charles R.; Christiansen, Robert L.; Clynne, Michael A.; Donnelly-Nolan, J. M.; Sherrod, D. R.; Smith, J. Cole (Field Trip Guidebooks Ser.)