undergraduate research · 2016-09-01 · Yuxin Zhou

In the spring of 2015 I conducted structural geology research in Sierra de Narvaez, Argentina, the northern end of the Famatinian arc, with a Permian-Carboniferous sedimentary package on top.

Using stereonets, I demonstrated the sequence of compression events in the area. Put into the context of an arc setting, the NE-SW compression event and the steep magmatic foliation may be the result of arc shortening and crustal thickening. Magmatic thickening, deformational thickening, and erosion may all played a role in the process.

As my senior thesis project, I built upon and improved an existing mass balance and isostacy model. I examined and refined the equations used in the model and ran the model through multiple sensitivity tests. Using newly collected data from arcs in northern Argentina, I applied the revised model to the Cordilleran Orogenic System to examine the model’s capability to reproduce the crustal thickness, elevation, and erosion rates over time scales of ~200 million years.

isostacy concept

Concept of an isostatically compensated crustal column adapted from Lee et al., 2015. E stands for erosion. T stands for tectonic thickening. M stands for magmatic thickening.