Abstract by Collin Jensen
Multi-stage construction of the Little Cottonwood Stock, Utah: Intrusion, venting, mineralization, and mass movement
The Little Cottonwood Stock (LCS) is a granitic intrusion in the Wasatch Mountains. It contains two smaller mineralized zones, the Red Pine Porphyry (RP) and the White Pine intrusion (WP), and also hosts pebble dikes. Our study is to determine the chemical and petrographic distinction between these units, remapping the region with our results, and determining the sequence of events of the construction of the mineralized deposit.
XRF geochemical data, petrographic data, and field mapping paint a picture more complex than originally known. There appear to be two distinct WP magmas separated by trace element levels. One of these WP units seems to have differentiated to the RP. All of these units have been extensively mineralized and altered.
Pebble dikes and quench textures are evidence for venting, and the associated hydrothermal system may have contributed to weakening the base of the overlying rocks, contributing to the mass movement of East Traverse Mountain landslide.