| In August 1991 staff from the David A. Johnston Cascades Volcano Observatory (CVO) in Vancouver, Washington, established an approximately 50 km by 100 km GPS network in the Lassen Peak area of Northern California ... to establish baseline measurements to detect crustal deformation that might be related to tectonic or volcanic processes. ... The purpose of this report is to provide a field guide for future researchers who may have a need to re-occupy the listed sites. It contains photographs and descriptions of the bench marks. -- Yamashita, et.al., 1995 |
