The book presents a full methodology for investigating heat flow and heat generation on a large scale (state). Detailed description of thermal conductivities measurements is given. Heat generation estimation is described. A thorough error analysis lends confidence to the final heat flow values. The book includes the first heat flow and heat generation maps of Oklahoma. The study is extended to the south central United States by incorporating additional heat flow data from neighboring states. Heat flow in Oklahoma appears to be consistent with that measured in other stable tectonic provinces...