Gauge Datum : (1) Vertical distance of the zero of a gauge referred to a certain datum. (2) The elevation of the zero of the gauge above a certain officially specified datum surface for leveling
CEDIM - Center for Disaster Management and Risk Reduction Technology, GFZ German Research Centre for Geosciences (Section 2.1 Earthquake Risk and Early Warning), CEDIM-Glossary (Terms and Definitions of Risk Sciences), Karlsruhe Institute of Technology (KIT), D-76128 Karlsruhe, Germany 2005. http: //www.cedim.de/download/glossar-gesamt-20050624.pd f, (Rsk Sci - Brit) {792}