Coyote Hill and the West Portillo mountains make up the western portion of the PVF, with regional velocities in this uplift ranging from 4.5 km/s to over 6.0 km/s at a depth of 2.5 km. To the east is the Malpais basin, where velocities range from 1.68 km/s to 4.86 km/s at a depth of approximately 3 km. The Mesilla basin is an asymmetric basin that adjoins the eastern edge of the PVF and extends on to the western flank of the Franklin mountain uplift. At a depth of about 1.5 km the velocities in the western area range from approximately 2.4 km/s to 4.0 km/s at a depth of about 1.5 km.