Efeito residual da modelagem topográfica (RTM) associado à variação da densidade lateral no Brasil

Residual topographic modeling (RTM) effect associated with lateral density variation in Brazil

Abstract

In this study, three representations of RTM behavior covering the entire continental territory of Brazil are presented. These utilize global models of variable lateral density: UNB_TopoDens and CRUST 1.0 (Sediments 1 and Water layers) and an average model (Harkness), with the global topography model ETOPO1 serving as the positional reference, at a station spacing of 5 arc minutes. Gravitational potentials were calculated using tesseroids and spherical zonals based on Newton's integral. The three models were tested for their means, which were found to be statistically different. Additionally, the differences in calculated values among the three density models were presented. The effect of RTM in Brazilian territory ranged from 0 to 2.5 mm, emphasizing its importance and consideration in precision altimetric studies. The developed methodology proved effective and encourages future work focusing on increasing positional and density resolutions, as well as processing with harmonic correction.