Seminar

Erosion redistributes mass of the upper crust and thus acts as a major driver of tectonic evolution across a wide range of length and time scales. However, we do not understand the upper limit of vertical rock motion and associated features that may result from erosion-dominated processes. It is more challenging because of the difficulty to decouple erosion-dominated processes from that of tectonic processes both in active systems and throughout the geologic record. Resolving this problem will provide new constraints on the overall dynamics of interactions between the solid Earth and focused erosional systems. In this study, I propose investigating a region that shows localized erosional focusing against a backdrop of homogeneous tectonics. This will help to know the relative contributions of erosion processes and dissect the overall crustal response. To articulate this (1) field-based structural mapping will determine deformed crustal geometries; (2) analytical determinations of mineral cooling ages will constrain rock exhumation rates; and (3) parameters from analogue and numerical models and results from (1) and (2) will enable 3D evolution reconstruction of a type-example of extreme crustal deformation in response to river-focused erosion. Present investigation of the Sutlej Valley shows extreme rock uplift/exhumation is concentrated in the core of a river anticline with variable erosion rate. This result will aid further investigation of tectonic structures within and outside the zone of rapid exhumation to constrain their kinematics.