Accurate determination of calibration factor for tidal gravity observation of a GWR-superconducting gravimeter

Introduction The superconducting gravimeters (SGs) are widely used to observe the change in temporal and spatial gravity field by many countries along the world, considering their characteristics as of the high-precision, good continuity and stability. By using the temporal variation of the tidal grav-ity obtained from the global network of SGs, the Global Geophysics Project (GGP) aims at some hot problems in geophysics and geodynamics (SUN, HSU, 1997). The original observations of the c…

Accurate determination of calibration factor for tidal gravity observation of a GWR-superconducting gravimeter

It is recognized widely nowadays that the superconducting gravimeter (SG) is a kind of best relative gravimeter with high observing precision, good continuity and stability. However, it is necessary to calibrate the direct output (change in voltage) by using scale value (calibration factor) before getting the change of the real gravity field. Studies show that the accuracy of the scale value will influence the late analysis and explanation of the observa-tions. By using absolute gravity measurements of a FG5 absolute gravimeter (AG) at Wuhan international tidal gravity fundamental station (two campaigns each for 3 days) and by using known tidal parameters at the same station, the calibration factors of the SG and their precision are studied in detail in this paper.