G. B. Dalrymple M. A. Lanphere J.C. Von Essen A.L. Berry 1976 Potassium-argon age measurements are reported for 61 mineral separates and rock samples from Alaska, Arizona, California, Idaho, Utah, and Washington. The age report for each sample gives location, analytical data, and a brief geologic interpretation. application/pdf 10.3133/cir727 en U.S. Geological Survey, Summary of miscellaneous potassium-argon age measurements, U.S. Geological Survey, Menlo Park, California, for the years 1972-74 reports