[PERSON]  
1 Yunnan Earthquake Agency, Kunming 650224, China; [EMAIL_ADDRESS] (Q.Z. ); [EMAIL_ADDRESS] (D.L. ); [EMAIL_ADDRESS] (Z.C.) [PERSON]  
1 Yunnan Earthquake Agency, Kunming 650224, China; [EMAIL_ADDRESS] (Q.Z. ); [EMAIL_ADDRESS] (D.L. ); [EMAIL_ADDRESS] (Z.C.) [PERSON]  
1 Yunnan Earthquake Agency, Kunming 650224, China; [EMAIL_ADDRESS] (Q.Z. ); [EMAIL_ADDRESS] (D.L. ); [EMAIL_ADDRESS] (Z.C.) [PERSON]  
1 Yunnan Earthquake Agency, Kunming 650224, China; [EMAIL_ADDRESS] (Q.Z. ); [EMAIL_ADDRESS] (D.L. ); [EMAIL_ADDRESS] (Z.C.) [PERSON]  
1 Yunnan Earthquake Agency, Kunming 650224, China; [EMAIL_ADDRESS] (Q.Z. ); [EMAIL_ADDRESS] (D.L. ); [EMAIL_ADDRESS] (Z.C.) [PERSON]  
1 Yunnan Earthquake Agency, Kunming 650224, China; [EMAIL_ADDRESS] (Q.Z. ); [EMAIL_ADDRESS] (D.L. ); [EMAIL_ADDRESS] (Z.C.) [PERSON]  
1 Yunnan Earthquake Agency, Kunming 650224, China; [EMAIL_ADDRESS] (Q.Z. ); [EMAIL_ADDRESS] (D.L. ); [EMAIL_ADDRESS] (Z.C.) [PERSON]  
1 Yunnan Earthquake Agency, Kunming 650224, China; [EMAIL_ADDRESS] (Q.Z. ); [EMAIL_ADDRESS] (D.L. ); [EMAIL_ADDRESS] (Z.C.) [PERSON]  
1 Yunnan Earthquake Agency, Kunming 650224, China; [EMAIL_ADDRESS] (Q.Z. ); [EMAIL_ADDRESS] (D.L. ); [EMAIL_ADDRESS] (Z.C.) [PERSON]  
1 Yunnan Earthquake Agency, Kunming 650224, China; [EMAIL_ADDRESS] (Q.Z. ); [EMAIL_ADDRESS] (D.L. ); [EMAIL_ADDRESS] (Z.C. ); [EMAIL_ADDRESS] (Z.C.) [PERSON]  
1 Yunnan Earthquake Agency, Kunming 650224, China; [EMAIL_ADDRESS] (Q.Z. ); [EMAIL_ADDRESS] (D.L. ); [EMAIL_ADDRESS] (Z.C.) [PERSON]  
1 Yunnan Earthquake Agency, Kunming 650224, China; [EMAIL_ADDRESS] (Q.Z. ); [EMAIL_ADDRESS] (D.L. ); [EMAIL_ADDRESS] (Z.C.) [PERSON]  
1 Yunnan Earthquake Agency, Kunming 650224, China; [EMAIL_ADDRESS] (Q.  
stations on Earth's surface are much closer to the field source, and the observed gravity signals can overcome the space resolution shortage (below 300 km) of gravity satellites. Terrestrial gravimetry is usually divided into relative gravimetry and absolute gravimetry [8; 9; 10; 11; 12; 13]. For decades, with rapid improvement of different high-accuracy gravimeters and development of dense gravity survey networks, repeated surface gravity observations have been available to study geoscientific problems such as crustal deformation [14; 15; 16], groundwater change [17; 18], oil, gas, and mineral exploration [19], glacier mass change [20], volcanoes [21; 22; 23], and earthquake precursor research [24; 25; 26; 27; 28; 29; 30]. A gravity signal obtained on Earth's surface is a typical microgravity signal, and the uncertainties of such gravity data are complex, including both observational errors and field source factors of gravity variations. Observational errors require improved data adjustment theory that considers scale factor (SF), instrumental drift, and other factors. The field source factors of gravity variations require observation and elucidation of those factors that affect gravity signals, e.g., rainfall, groundwater, surface deformation, and air pressure. In fact, the former are the main factors, while the latter are complex and difficult to estimate quantitatively, and some errors are so small (<10 \(\mu\)Gal) to be negligible [31]. Therefore, this study focused primarily on evaluating the quality of data in relation to the uncertainties of instruments. Absolute gravimeters (e.g., the FG-5 and A-10 gravimeters) can provide direct gravity values with high accuracy; however, they tend to be too expensive, are generally cumbersome, and have rigorous requirements for the observation environment. Although relative instruments can only provide measurements of gravity variations, they are more economical, portable, and have minimal environmental requirements which making it suitable for large-scale field work. Moreover, depending on the control of absolute gravity (AG) values in the survey network, it is possible to obtain large-scale and high-precision terrestrial time-variable microgravity datasets.