Compilation geologic map of the Oracle 7.5' Quadrangle, Pinal and Pima Counties, Arizona

The Oracle 7.5' Quadrangle is located approximately 40 km north-northeast of downtown Tucson, and is on the northwest flank of Santa Catalina Mountains (Figure 1). The quadrangle encompasses the northwestern comer of the range, some of the flanking pediment around the town of Oracle, and alluvium in northeastern Oro Valley. The area was mapped during October 1999 to April 2000 as part of a multiyear mapping program directed at producing complete geologic map coverage for the Phoenix-Tucson metropolitan corridor. A 1 :24,000 scale map is the primary product of this study (Plate 1). This map incorporates past mapping by other workers as well new mapping by the authors (Figure 2). The accompanying report describes rock units and other geologic features. This mapping was done under the joint State-Federal STATEMAP program, as specified in the National Geologic Mapping Act of 1992. Mapping was jointly funded by the Arizona Geological Survey and the U.S. Geological Survey under STATEMAP Program Contract #99HQAGOI71.