Articles | Volume 14, issue 2
https://doi.org/10.5194/gi-14-423-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gi-14-423-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
03 Dec 2025
Research article |
| 03 Dec 2025
| 03 Dec 2025
The multi scenarios applicability of GNSS differential positioning technology in the remeasurement of observatory azimuth in China
Yufei He
Institute of Geophysics, China Earthquake Administration, Beijing, 100081, China
Beijing Baijiatuan Earth Sciences, National Observation and Research Station, Beijing 100095, China
Institute of Geophysics, China Earthquake Administration, Beijing, 100081, China
Beijing Baijiatuan Earth Sciences, National Observation and Research Station, Beijing 100095, China
Suqin Zhang
Institute of Geophysics, China Earthquake Administration, Beijing, 100081, China
Qi Li
Institute of Geophysics, China Earthquake Administration, Beijing, 100081, China
Fuxi Yang
Xinjiang Earthquake Administration, Urumqi, 830011, China
Shaopeng He
Hebei Earthquake Administration, Shijiazhuang, 230071, China
Pengkun Guo
Hebei Earthquake Administration, Shijiazhuang, 230071, China
Jinping Zhou
Institute of Geophysics, China Earthquake Administration, Beijing, 100081, China
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This study evaluates the data quality and long-term robustness of reference fluxgate theodolites in Geomagnetic Network of China (GNC). Results show high stability in reference instruments and no drift. Operator dependent errors were identified as the primary contributor in observer data. The study highlights the critical role of comparisons. Future efforts should integrate sensors and automation technologies to minimize human errors, thereby providing a higher quality data for studies.
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The objective of this study is to rescue and integrate historical data from eight pioneering geomagnetic observatories in China. Data quality is significantly improved through integration. The integrated dataset is now publicly available for easy access and use by the academic community and the public. These datasets are of great significance for optimizing historical geomagnetic field models and investigating changing magnetic fields, the main geomagnetic field.
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Nearly 200 sets of three-axis fluxgate magnetometers are used in Chinese geomagnetic observatories, but due to their directional errors, it is necessary to study error correction methods to improve measurement accuracy. Experimental results show that correcting the Z-axis and D-axis directional errors is essential. The observation data after error correction demonstrate the clear correction effect. The measurement device used in the experiment is low in cost and easy to disseminate.
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The Sheshan observatory has nearly 150 years of observation history, and its observation data have important scientific value. However, with time, these precious historical data face the risk of damage and loss. We have carried out a series of rescues on the historical data of the Sheshan observatory. New historical datasets were released, including the quality-controlled absolute hourly mean values of three components (D, H, and Z) from 1933 to 2019.
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Preprint withdrawn
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The daily variation amplitude of geomagnetic component Z could represent the diurnal variation strength of geomagnetic field. The ionospheric conductivity, neutral wind in ionosphere and the complicated underground electrical structures make combined action to effect the feature of the Z daily variation amplitude in China. This paper will provide the background information or reference to researchers who study the geomagnetic diurnal variation or to analyse the anomaly.
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Short summary
This study establishes Global Navigation Satellite System (GNSS)-based azimuth remeasurement scenarios for geomagnetic observatories. Five prioritized workflows address diverse field conditions. Validations at Hongshan, Quanzhou, and Yulin observatories confirm Scenario I (flat and clear line of sight) and Scenario II (alternative clear path available) feasibility. Preliminary error analysis informs a deployment priority sequence, providing scalable solutions for complex environments.
This study establishes Global Navigation Satellite System (GNSS)-based azimuth remeasurement...
