Continental rifting is characterized by structural asymmetry of the earth's crust as evidenced by the predominance of tilted fault- blocks in most extended terranes. Accommodation zones facilitate periodic reversals in the sense of rift asymmetry, including inversion in the dominant direction of block-tilting and possibly reversal in the dip of regional detachment systems. The amount and direction of movement of the upper and lower plate rocks will dictate the deformational style along the accommodation zone, therefore studies of such zones can provide constraints on the kinematic evolution of individual detachment terranes. This project is a detailed mapping, structural analysis and paleomagnetic investigation of a well-exposed accommodation zone in the Black Mountains of Arizona and the Eldorado Mountains of Nevada. These investigations of this accommodation zone may have important ramifications for the geometry and processes attending continental rifting.