Gravity reduction schemes, particularly residual terrain model and terrain corrections, constitute one of the main shortcomings of gravity databases in African countries. The calculation of these quantities often requires the evaluation of several parameters for selecting the height database, the digital terrain model and the integration radii. The article aims to develop high-resolution spatial grids of gravity terrain corrections (TC) and the residual terrain model (RTM) for Cameroon based on a global numerical approach. The digital elevation/bathymetry (DEM/DBM) created with a global resolution of 1 arc-second (~30 m) was obtained by merging the SRTM1 model for the mainland zone and the SRTM15+ model for the marine zone, and constitutes the main data for modeling terrain effects. Computations were based on terrestrial gravity stations and a grid of points regularly spaced 1.5 arc-minutes apart, with integration radii of 20 and 200 km for inner and outer zones respectively, and a standard density of 2670 kg/m？3. In addition, low-pass filtered mean elevation surfaces, with spatial scales of ~100 km and ~9 km respectively, were used to calculate RTM effects. Local data of terrain corrections published for the first time in Cameroon show 91.25% of terrain corrections below 1 mGal, with only 38.43% of values below 0.10 mGal for terrestrial gravity stations, and 8.31% of values between 1 and 10 mGal. Data on RTM effects with a spatial scale of ~9 km show 87.03% of direct effects below 5 mGal, while RTM effects with a spatial scale of ~100 km show 74.89% of direct effects below 5 mGal. The data of this study have a number of applications in geophysics and geodesy, which require accurate spatial resolutions for calculating terrain effects in order to properly reduce gravimetric observations.
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