Does draping aeromagnetic data reduce terrain-induced effects?

In cases where draped surfaces are lower than level surfaces, the draped profiles exhibit steeper gradients and deeper polarity lows over topography than do the level profiles. On the other hand, where draped surfaces are higher than level surfaces, all anomalies are attenuated, so that magnetic-terrain effects might be reduced relative to subsurface sources. The difference in magnetic behavior between level and draped data can be explained by a contribution of a vertical derivative component in the draped case that is absent in the level case. The contribution is most significant near topographic features.--Modified journal abstract.