The ‘modern revolution’ in the Earth sciences is associated with the emergence of plate tectonics in the late 1960s. The assumption that the crust of the Earth was composed of a small number of rigid, non-deformable, mobile plates enabled a quantitative, kinematic description of current geological processes and reconstructions of past plate interactions. The simple model of plate theory c. 1970, for example its depiction of a subduction zone, has since undergone considerable refinement. However, some geologists, especially those concerned with questions of continental tectonics, contend that plate theory in its current form is of limited value in addressing questions of continental tectonics, and prefer to employ the concept of allochthonous terranes in characterizing, describing and interpreting regional geology. These geologists may understandably take the view that plate tectonics is a kinematic grand generalization but thus far not particularly useful in making sense of the rocks at the local level.