Repeat microgravity data from Phoenix, Arizona, 2020-2023
Dates
Publication Date
2024-12-20
Start Date
2020-01-27
End Date
2023-02-08
Citation
Kennedy, J.R., 2024, Repeat microgravity data from Phoenix, Arizona, 2020-2023: U.S. Geological Survey data release, https://doi.org/10.5066/P96Q1OZG.
Summary
This dataset represents the network-adjusted results of relative- and absolute-gravity surveys performed from 2020 to 2023 in and near the city of Phoenix, Arizona. Relative surveys were done using a Zero Length Spring, Inc. Burris relative-gravity meter. Absolute-gravity surveys were done using a Micro-g LaCoste, Inc. A-10 absolute-gravity meter. The effect of solid Earth tides and ocean loading were removed from the data prior to network adjustment. Non-linear instrument drift was removed by evaluating gravity change during repeated measurements at one or more base stations. Vertical gradients between the relative- and absolute-gravity meters were measured at each station where both types of measurement were collected to correlate [...]
Summary
This dataset represents the network-adjusted results of relative- and absolute-gravity surveys performed from 2020 to 2023 in and near the city of Phoenix, Arizona. Relative surveys were done using a Zero Length Spring, Inc. Burris relative-gravity meter. Absolute-gravity surveys were done using a Micro-g LaCoste, Inc. A-10 absolute-gravity meter. The effect of solid Earth tides and ocean loading were removed from the data prior to network adjustment. Non-linear instrument drift was removed by evaluating gravity change during repeated measurements at one or more base stations. Vertical gradients between the relative- and absolute-gravity meters were measured at each station where both types of measurement were collected to correlate the measurements of the two instruments. Vertical gradients were measured using a relative-gravity meter and tripod set to the height of the absolute-gravity meter. Relative-gravity differences and absolute-gravity data were combined using least-squares network adjustment, as implemented in the software GSadjust (https://code.usgs.gov/sgp/gsadjust). Data are provided for 105 stations collected over 4 discrete, annual surveys.
Gravity data were collected to evaluate aquifer-storage change and aquifer-storage properties. Using the horizontal infinite-slab approximation, gravity data can be converted to a thickness of free-standing water (Pool and Eychaner, 1995). Because data are not corrected for soil-moisture variation, estimated storage changes include all storage change in the vadose zone.
Rights
This work is marked with Creative Commons Zero v1.0 Universal (https://creativecommons.org/publicdomain/zero/1.0/).