“…The main feature on this crustal section is a thickening of the crust from 28 to 32 km, over a horizontal distance of 15-20 km, east of Clifton/Morenci. This thickening roughly coincides with the steep gravity gradient mapped by Boler et al (1980), and may be related. The general nature of the seismic crustal profile does not allow a direct spatial correlation with the gravity map, but crustal thickening of the seismic profile is probably associated with increasing elevations to the east.…”