Douglas B Yager



University College University of Denver, Certificate of Advanced Studies in GIS 1998

University of Colorado at Boulder, M.S. Geology 1995

Colorado State University, B.S. Geology, 1984


Geologist, U.S. Geological Survey, 1985–present


Douglas Yager has extensive experience working in volcanic and mineralized terrain as part of abandoned mine lands investigations.  Much of his USGS career has focused on the San Juan Mountains, in the southern Rocky Mountain volcanic field, Colorado, where he has worked on hydrothermally altered volcanic rocks that are host to precious- and base-metals extensively mined there since the late 1870’s.  Doug has co-led several field trips and student field courses in the San Juan Mountains.  His work on acid neutralizing capacity of propylitically altered lavas has aided in understanding possible alternative methods of mine land cleanup.  His watershed approach to analyzing geologic parameters that control surface water and groundwater geochemistry helps to identify source areas for potential mineral deposits and can be used to prioritize and rank watersheds based on the severity of water quality impacts from mining-related and natural sources of acidity and metals to streams. He currently is a project co-leader for developing a 3-D geologic and geophysical model of the San-Juan and Silverton caldera complex in Silverton, Colorado.