Description: Transportable spring gravimeters have many applications besides exploration geophysics and potential field determination, such as time-lapse measurements in hydrology and volcanology. For maximum accuracy, the time-dependent scale factor of each gravimeter must be determined before and after use. The required scale uncertainty depends on the target signals, the maximum gravity difference in the network, and the desired level of accuracy. In high alpine regions, large height differences can result in gravity differences of more than 1⋅10^6 nm/s^2. For a target uncertainty of 30 nm/s^2, the scale factor must be determined with an uncertainty below 1⋅10^(-5). The Zugspitze Calibration System, near Garmisch-Partenkirchen in the German Alps, consists of three absolute gravity (AG) stations that cover an elevation range of 2,200 m and a gravity range of 5,220 µm/s^2: W200 at Wank valley station (735 m a.s.l.) and W100 at Wank mountain station (1,738 m a.s.l.) at the cable car leading to Wank mountain, as well as the Zugspitze Geodynamic Observatory Germany (ZUGOG) at Zugspitze (2,939 m a.s.l.), where the OSG 052 superconducting gravimeter continuously measures gravity acceleration with the highest precision (1 nm/s^2) and long-term stability. Due to unmodeled temporary gravity changes, primarily caused by variations in snow water equivalent and groundwater, the system has a relative stability of approximately 5⋅10^(-5). To obtain gravimeter scale factors with an uncertainty below 1⋅10^(-5) in the Zugspitze Calibration System, we increase the precision by taking many measurements and improve the systematic uncertainty by modeling. From December 2023 to April 2026, a total of 73 difference measurements were taken between W200 and W100 using the relative gravimeters Scintrex CG6#362 from GFZ and CG6#171 from project partner LUH. Additionally, 18 difference measurements were carried out between W200 and ZUGOG. The CG6 measurements employed gravity gradients from Timmen et al. (2021) and tidal parameters from six years of SG measurements at Zugspitze. To correct for atmospheric variations, an air pressure admittance factor of -3 nm/s^2/hPa was used. The attached data have been calibrated using the initial scale factor specified by the manufacturer, and corrected for gravity gradients, tides, and atmospheric pressure variations.
Global identifier:
Doi(
"10.5880/GFZ.DQTO.2026.001",
)
Tags: Deutschland ? Schnee ? Grundwasser ? Wasser ? Modellierung ? Alpen ? Daten ? Gezeiten ? Hydrologie ? Tal ? Relative gravimetry ? Science Keywords > EARTH SCIENCE > SOLID EARTH > GRAVITY/GRAVITATIONAL FIELD > GRAVITY ? Scintrex CG6 ? Zugspitze Gravimeter Calibration System ? scale factor ? scale uncertainty ?
License: Creative Commons Namensnennung 4.0
Language: Englisch/English
Issued: 2026-01-01
Last harvest: 01.07.2026 00:11
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