Individual measurements of heat flow, or even a number of measurements made over a region, only have relevance to the immediate area. To understand the significance of individual heat flow measurements in a global sense, we need to investigate the geothermal signatures of various tectonic features. Only in this way can anomalous locations be identified and understood.

Crustal tectonism is the surface expression of phenomena that operate on the lithospheric scale. The lithosphere is that section of the upper mantle that exhibits gross plastic behaviour under stress. It can be thought of as a raft of mantle material upon which the crust rides. As such, it is the dominant control on surface heat flow in oceanic crust, and it contributes approximately half of the surface heat flow in continental areas (the other half arises from radiogenic sources within the crust). Tectonic features such as hot spots, subduction zones, and regions of crustal extension can be modelled on the lithospheric scale. Such models provide insights into the occurrence of volcanism and the distribution of heat in sedimentary basins.