The aim of this research is to tailor the Experimental Gravity Field Model [XGM2016] harmonic model to Egypt for better modeling of the Egyptian gravity field. This can be made by computing the differences between local gravity anomalies and those derived from the geopotential model, then the harmonic analysis of the residual gravity anomalies yields correction terms that are added to the original spherical coefficients of the relevant model to give the final modified coefficients of the fitted model.
Several methods can be used to achieve the tailoring process, in this paper; we have used the integral formulas, suggested by (Weber and Zomorrodian, 1988).
In this study XGM2016 has been tailored to fit the gravity data in Egypt using integral formulas in order to be used for the reference gravity field model for the Egyptian territory, according to its superior performance in previous study (Moamen et. al, 2017).
The results illustrated that the tailored model of XGM2016 denoted as EGXGM2016 has perfect performance, where its mean value is [1.56 mgal], the standard deviation is [10.50 mgal] and the range of the reduced gravity anomalies to EXGM2016 compared with XGM2016 have lesser values by about [43.52 mgal ] and the stander deviation is better by 62%. While the external accuracy by using [71 free air gravity anomaly data points] denoted that 54% lesser in terms of stander deviation.
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