Heat flow is a measure of the flow of heat in mW/m2 through rock.  It is one of the basic components of determining temperature at depth and calculating the long term MWth output of a geothermal reservoir.  Thermal conductivity of various rock lithologies is assembled in a 3D profile for the continent to a depth of 10km.  The EGS mapping protocol was developed by HDR Technical Director Graeme Beardsmore in conjunction with Southern Methodist University as part of a project funded by google.org.