Revision History for USGS Open-File Report 2010-1112 G.A. Phelps Evaluating the Feasibility of Modeling the Subsurface Structure of Two Volcanic Units in Drill Holes UE-18r and ER-EC-2a Using Existing Magnetic Data, Nevada Test Site ----------------------------------------------------- Posted online at http://pubs.usgs.gov/of/2010/1112/ July 21, 2010 -----------------------------------------------------