Beyond Plate Tectonics: What Do We Do in Structural Geology?

The major progresses of the global tectonics and structural geology in the last 10 years are reviewed. The new global tectonics that emerged three decades ago profoundly changed our understanding of the earth and its evolution. Plate tectonics as a unifying theory of the earth mainly is connected with deformation, seismicity and volcanism within plate boundaries. No comprehensive theory accounts satisfactorily for the driven force of plate motion and mechanism of mantle convection. Many of the problems of plate boundary formation and inter-plate formation remain unanswered. Continental lithosphere is significantly different from oceanic lithosphere in the aspects of composition, thickness and mechanical strength. However, the plate tectonics is not applied to continental tectonics as well. Comprehensive study for rheology of continental crust and the upper mantle is the best way in understanding continental structure and beyond plate tectonics. Rheology is the liaison between geometry and dynamics of continental orogeny. Responses of continental lithosphere to structuring, gravitation and thermodynamics largely depend on its rheological strength. Rheological strength of continental lithosphere is closely connected with stratification and heterogeneity. The pervasive deformation and internal structure of wide continental orogenic belts indicate non-rigid behavior. Continental tectonics and mechanical behavior are controlled by strength that resides mainly in the crust rather than in the mantle. From the view of multi-layering and mechanical heterogeneity of continental lithosphere, it is time to abandon the sandwich model. Facing development trend of earth science system and new thinking of geodynamics, multidisciplinary study on continental structure (orogenic belts) and promptly training outstanding talent is an urgent task.