DOI: 10.5281/zenodo.18584557
title: Time-varying gravity constraints on groundwater recharge and managed aquifer strategies in southern Taiwan

description: This dataset supports the paper:

Chen, K.-H., Hwang, C.* et al.  "Time-varying gravity constraints on groundwater recharge and managed aquifer strategies in southern Taiwan",  [Water Resources Research], accepted.

The dataset contains gravity, groundwater level, and supporting hydrologic data collected along the Ailiao River, Pingtung Alluvial Plain, Taiwan, between November 2023 and July 2025.

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## Dataset overview

Seven super-hybrid gravity surveys were conducted using a combination of absolute (FG5), relative (CG-5 / CG-6), and superconducting (SG48) gravimeters. The data are organized by survey periods and instrument type, together with collocated groundwater level measurements.

The dataset corresponds to the Data Availability statement and Sections 2?? of the paper.

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## Folder and file structure

### `Survey 1-2/`Relative gravity observations from Surveys 1 and 2 (Nov?ec 2023).

- Instrument: Scintrex CG-5  - Reference: Absolute gravity station YFA1 (FG5)  - Content includes raw and processed relative gravity readings, loop measurements, and drift-corrected values.- Corresponds to Table 1 and Sections 2.2??.3 of the paper.

### `Survey 3-5/`Relative gravity observations from Surveys 3?? (Aug 2024?an 2025).

- Instrument: Scintrex CG-6  - Reference: YFA1 gravity values propagated from SG48 (Hsinchu) during FG5 downtime  - Content includes loop logs, processed gravity values, and network-adjusted results.- Corresponds to Table 1, Appendices A?, and Sections 2.2??.3.

### `Survey 6-7/`Relative gravity observations from Surveys 6 and 7 (May?uly 2025).

- Instrument: Scintrex CG-6  - Reference: Absolute gravity station YFA1 (FG5 restored)  - Includes expanded network data for recharge-lake and downgradient stations (AL01?L09, FH00, YP00).- Corresponds to Table 1, Figure 9, and Appendix C.

### `groundwater monitoring well/`Groundwater level measurements used to interpret gravity-derived storage changes.

- Includes groundwater levels from BH01, MJMW, and other long-term monitoring wells.- Used for gravity?roundwater comparisons and specific yield estimation (Sections 4??).

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## Individual files

### `FG5_YP01.xlsx`Absolute gravity measurements collected with the FG5 gravimeter.

- Location: YFA1 / YP01 absolute gravity station- Content: observation epochs, gravity values, and standard deviations- Used as the absolute reference for Surveys 1?? and 6??.

### `MAJA and BH01-GW and Gravity.csv`Collocated groundwater level and gravity data.

- Includes groundwater levels and corresponding gravity changes at MJMW and BH01- Used to evaluate recharge timing, unsaturated-zone effects, and gravity?roundwater relationships (Sections 4.1??.1).

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## Units and conventions

- Gravity values: microgal (繕Gal)- Groundwater levels: meters (m), orthometric heights under TWVD2001- Gravity changes are reported relative to the first observation at each station unless otherwise stated.- Positive gravity change indicates increased subsurface water mass.

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## Coordinates and policy

Station coordinates are provided where required and are rounded to comply with journal and data-sharing policies. Exact locations of sensitive infrastructure are not disclosed.

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## License and access

- License: Creative Commons Attribution 4.0 (CC-BY 4.0)- Data archived on Zenodo.- Interim access was provided to the editor during review upon request.

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## Contact

Corresponding author:  Cheinway Hwang  Department of Civil Engineering, National Yang Ming Chiao Tung University  Email: cheinway@nycu.edu.tw