From the Abstract: "The study area, a classic metamorphic core complex, actually shows the characteristic features of such complexes only at the southern end of the range and grades into other rock assemblages to the north. The area thus affords the opportunity of analyzing the definitive components of a core complex separately. It measures about 48 by 11 km, traversing the central par t of the Santa Catalina Mountains from the Tucson basin to the San Pedro basin. The dimensions of study lend themselves to a cross-sectional approach. A supracrustal sequence 1.1 km thick consists of Middle Proterozoic Apache Group and Paleozoic rocks unconformably overlying mostly-granitic basement rocks. Units of special interest include voluminous pyroclastic rocks in the Pioneer Formation, glaciomarine rocks of Upper Proterozoic age, and ?Devonian fluvial deposits in a paleochannel on Mt. Lemmon. Laramide intrusions of roughly granodioritic composition are mostly concordant, typically inflate the supracrustal sequence about 300 m, and define three mutually exclusive large domains. The two domains characterized by Leatherwood and San Manuel intrusions show impressive heating and alteration effects, whereas the central domain characterized by Rice Peak intrusions show few such effects due apparently to multiple small intrusions."