Abstract
Global Positioning System (GPS) surveys were undertaken in 1984 and repeated in 1985 along level lines in southeastern Arizona where subsidence induced by groundwater withdrawal was occurring. The objective of these surveys was to determine the accuracy with which subsidence could be determined both from comparison of repeat GPS measurements and from comparison of GPS measurements with existing leveling. Repeatability of GPS determinations of differential ellipsoid height during a single survey was at the 1–2‐cm level. Differencing results of repeat GPS surveys performed 15 months apart gave subsidence values that agreed at the 2–4‐cm level with those obtained from leveling. Also, it was found that, after using gravimetric geoid heights to convert GPS‐derived ellipsoid heights to orthometric heights, agreement between the GPS/geoid orthofnetric heights and leveling orthometric heights was in the 3–7‐cm range. These results show that repeated GPS measurements can be used to monitor future subsidence in sou...
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
