2020 Hochstetter Lecture - Phaedra Upton (Nelson)

The landscape serves as a link between the solid Earth and the atmosphere. At many spatial and temporal scales, landscape morphology and topography provide a constraint on the tectonics of the deeper Earth and the processes active within it. To unravel these, we need to understand the complex relationships between surface processes, their drivers and the rocks upon which they act. Phaedra will explore recent developments in modelling tectonics and surface processes within a single deformational framework. She will focus on collisional settings such as New Zealand’s Southern Alps, SE Alaska and the Himalaya where rapid uplift combines with vigorous climate regimes to create dynamic landscapes.

3D mechanical models, constrained by field observations, are solved for the complete stress tensor, including both geodynamic and geomorphic components (tectonic, dynamic, topography, fluvial, glacial). They also predict where imposed tectonic driving forces result in deformation-induced weakening of the rock mass in the form of faults and other structures. The balance between the rock strength and 3D stresses acting upon the rock mass determines whether or not rock at the surface breaks, which makes it potentially available to be acted upon by surface processes.

About the speaker

Phaedra Upton is the Geodynamics Team Leader at GNS Science, where she has worked for the last 11 years.  She has widely published on oblique collisional plate boundaries including the Southern Alps.  More recently, tectonic geomorphology has become her main focus. 

As a modeller, Phaedra tries to bring practical and sensible numerical modelling approaches to a wide range of Earth Science topics, from large scale processes in the deep crust through to surface processes of active erosion and sedimentation.  She is adept at using these models in collaboration with geologists from a range of subdisciplines to produce insights into the various processes and time scales involved.