The low crust of the PVF has a uniform density of 2880 kg/m3. The upper to middle crust (between 5 km and 20 km) of the PVF includes a block with a density of 2740 kg/m3. The density at is 2880 kg/m3. This body is a mid-crustal "welt" and velocities within this region increase to more than 6.35 km/s. This greater density creates a lateral density contrast and in turn generates a long-wavelength gravity high. The upper mantle densities at the PVF decrease from 3280 to 3250 kg/m3 from west to east, based on a decrease in velocities from approximately 7.96 to 7.70 km/s.