Distant Relief Effect and Its Possible Impact on Large-Scale Gravity Interpretations

In gravimetry, the topography and bathymetry beyond the angular distance of approximately 1.5 degree from the point of calculation (we call it distant relief) is conventionally not accounted for. However, the availability of powerful personal computers as well as satellite digital elevation models, allows us to estimate the effects of those features on the measured gravity and thus also on the values of Bouguer anomalies. Using an approximate spherical Earth model, we have calculated distant relief effect as well as its vertical gradient within the territory of Central Europe. We show that although distant relief effect varies relatively slowly in the study area, it can occasionally be considered in the framework of large-scale gravity studies. On the other hand, vertical gradient of the distant relief effect is practically negligible.