Original topography \~. ^ True valley fill bedrock O - O - Os contact O ~
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Figure 20.
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Once the gravity contributions of the valley fill in the topography model have been removed, the remaining valley fill can be modeled efficiently using blocks. Note that with the removal of the gravity contributions of the valley fill included in the topography model, it is not as if the gravity stations have been dropped to the plane at the base of the topography model. en eo