Vertical Land Motion Global Navigation Satellite System (GNSS) Campaigns, Southeast Virginia (ver. 2.0, December 2022)

This data release is a compilation of annual Global Navigation Satellite System (GNSS) surveys of a network of 26 vertical control points (benchmarks) in the Hampton Roads region of southeastern Virginia. Surveys are conducted annually during the winter and are structured to collect a minimum of 24-hours of position data when possible, at an interval of 30-seconds or less at each benchmark location. Raw GPS survey files are downloaded and converted to Receiver Independent Exchange Format (RINEX) and post processed using the National Oceanic and Atmospheric Administration (NOAA) National Geodetic Survey (NGS) Online User Positioning Service (OPUS) Projects 4.12 software package following guidance and best practices from the NGS. The HRBenchmarks_results_2018, 2019, 2020, 2021, and 2022 CSV files summarize the annual ellipsoid heights, in meters, and associated metadata for each benchmark surveyed for that year. Ellipsoid heights are referenced to the International Terrestrial Reference Frame 2014 (ITRF2014) at epoch 2010.000 and the epoch effective at the time of data collection. Raw GNSS observation data from seven (7) of the benchmarks are collected by collaborating federal agencies using consistent techniques and methods (Rydland and Densmore, 2012) and provided to the USGS for inclusion in the study. Data collection efforts were completed in 2022.