Heat flow values are a measure of the heat flux moving from the Earth’s interior to the surface. High heat flow values can indicate various geologic situations such as 1) an area of relatively thinner crustal rock above the mantle, 2) presence of an igneous pluton, resident heat from geologically recent volcanism or plutonic activity, and 4) upwelling of deep, heated groundwater.
1 plate (1:1,000,000). See MS-45. Digital PDF download. MS-18D
From the Abstract:
Regionally, Colorado is separated into three heat flow provinces. They are: the Great Plains, the Southern Rocky Mountains, and the Colorado Plateau provinces. The Great Plains province, except for the Raton Basin and Canon City Embayment, indicates normal heat flow. The Southern Rocky Mountain province which encompasses both the Rio Grande Rift and an anomalous zone located near Ouray are the most promising areas for high heat flow. The Colorado Plateau province is considered normal to slightly above normal compared with the regional heat flow of the United States.
This 1981 map shows contoured heat flow with a contour interval of 20 mW/m2. Contours range from 60 to 160 mW/m2. Note that this product was updated in 2008 by MS-45 “Interpretative Geothermal Heat Flow of Colorado”.