Magnetic total intensity anomalies in northern and central Arizona have been analyzed to locate the bases of the polarized source bodies. The base of the magnetic crust is interpreted as the position of the Curie point isotherm. Results indicate a zone of shallow Curie depth (∼10 km) in a belt, about 60 km wide, running through the center of the state. This zone, near the northern border of the Basin‐Range province, is flanked on the north and south by areas of greater Curie depth (∼20 km). The results are in agreement with regional variations in [Formula: see text] velocity in Arizona.