This report presents a preliminary 1:24,000-scale geologic map of the northeastern Hieroglyphic Mountains in central Arizona. The mapping, completed between January and June, 1986, was jointly funded by the U. S. Geological Survey and the Arizona Bureau of Geology and Mineral Technology as part of the cost-sharing, Cooperative Geologic Mapping Program (COGEOMAP). The aim of COGEOMAP is to produce high-quality geologic maps for areas that have been inadequately mapped and that have high mineral resource or natural hazard potential. The mapping was done on 1:24,000-scale topographic maps and on 1:24,000- scale color aerial photographs provided by Raymond A. Brady, U. S. Bureau of Land Management, Phoenix.