Southwest Gravity Program Absolute-Gravity Database (updated 2025-12-19)

This dataset contains absolute-gravity data collected by the USGS Southwest Gravity Program, a collaborative effort of the Arizona, California, and New Mexico Water Science Centers to monitor and model groundwater-storage change.

Data were collected following the methods in "Procedures for Field Data Collection, Processing, Quality Assurance and Quality Control, and Archiving of Relative and Absolute-Gravity Surveys, U.S. Geological Survey Techniques and Methods book 2, chapter D4. All data are reviewed and approved. Additional gravity data, including network-adjusted relative- and absolute-gravity data, may be available in ScienceBase Data Releases.

Gravity data are provided as two files:

sgp_agdb_stations_YYYY-MM-DD.csv contains station information and measurement metadata (date of first and last observations, and so on)
sgp_agdb_measurements_YYYY-MM-DD.csv contains measured gravity values and associated metadata.
Data are also available for viewing and downloading through a map-based viewer at the link under "Related External Resources," below.

This dataset will be updated as new absolute-gravity data are collected and approved. Changes are documented in sgp_agdb_ChangeLog.txt

本数据集包含由美国地质调查局（USGS）西南重力项目采集的绝对重力数据，该项目由亚利桑那、加利福尼亚与新墨西哥州水资源科学中心联合开展，旨在监测并模拟地下水储量变化。

数据采集严格遵循《美国地质调查局技术与方法丛书第2卷D4章：相对与绝对重力测量的野外数据采集、处理、质量保障与质量控制及归档规程》中的规范执行。所有数据均经过审核与批准。包含经网络平差的相对及绝对重力数据在内的额外重力数据，可在ScienceBase数据发布平台获取。

重力数据以两个文件形式提供：
sgp_agdb_stations_YYYY-MM-DD.csv 包含测站信息与测量元数据（如首次及末次观测日期等）
sgp_agdb_measurements_YYYY-MM-DD.csv 包含实测重力值及相关元数据。

用户还可通过下方“相关外部资源”链接处的地图式查看器，浏览并下载本数据集。

本数据集将随新采集并通过审核的绝对重力数据持续更新，所有变更记录均存档于sgp_agdb_ChangeLog.txt 文件中。