  Lithosphere is an outer rigid part of the terrestrial body, usually
consisting of the crust and part of the mantle. Characterizing the physical
properties of the lithosphere is critical in investigating its evolution. By
modeling mass-related loads within the lithosphere, physical parameters such as
the elastic thickness of the lithosphere can be inferred from gravity and
topography data. In the impact basin region, however, the low
topography-gravity correlation and the sharp change in admittance from negative
to positive within a narrow spheric harmonic degree make this model
inapplicable. In this work, we incorporated mantle uplift structures commonly
formed in impact basin regions into the lithospheric loading model. The
crustal-mantle boundary of this mantle uplift structure is inferred from the
global crustal thickness model. The gravity anomaly of the deflected
lithosphere is calculated at the surface and crustal-mantle boundary, then the
theoretical gravity admittance and correlation can be compared with the
observed data. We sampled parameters using this mantle loading model at Argyre
and Isidis basin on Mars with a novel crustal thickness model from the InSight
mission. Our work suggests that proper modelling of the impact-induced load is
critical to understanding the physical properties of the planetary lithosphere
in the basin region.
