This publication presents a tabulation of the temperature and associated data of subsurface rocks and two maps showing the location of wells for which temperature information is available in the files of the Oil and Gas Conservation Commission. Most of this information consists of the bottomhole temperatures measured by geophysical log surveys of wells drilled for oil, natural gas, and helium in the northeastern portion of the Colorado Plateau tectonic province of Arizona. It represents the first phase of a subsurface temperature project designed primarily for the use of earth scientists interested in the geothermal-energy potential of the state. The second phase of the project will present surface water temperature and associated data of numerous wells drilled for irrigation and other purposes located mostly in the Basin and Range tectonic province of Arizona.