A Comparison Between Structure–From–Motion Photogrammetry and Field Measurements That Helps Identify Fluid Pathways Within Detachment Shear Zones

Niya Davis, Auburn University
Raphaël Gottardi, Auburn University

Abstract

Fluids play a major role in strain localization in detachment shear zones. The rheology of the continental lithosphere is controlled by brittle failure in the upper crust and ductile flow in the middle to lower crust. Due to our limited understanding of how surface fluids interact with rock deformation within the well-known Miocene Raft River detachment shear zone (Utah), our knowledge of how meteoric fluids move beyond the brittle-ductile transition remains incomplete. We propose that large fault and fracture networks may have served as fluid pathways for surface fluids to reach the middle crust. Our main challenge is conducting a comprehensive fault and fracture analysis in the region because of accessibility issues. The Raft River detachment shear zone is well exposed in the Clear Creek Canyon, but this area features vertical escarpments and poor fault exposure due to dense vegetation. To address this, we will use various methods, including remote sensing (satellite imagery), drone-based aerial imagery, and fieldwork, to perform our structural analysis. We will focus on using structure-from-motion photogrammetry to reconstruct 3D models of the outcrops for our analysis. This approach will enable us to perform structural assessments over a broader region than what is visible in the field, which will significantly improve the accuracy of our analysis. Combining remote sensing with fieldwork will deepen our understanding of fluid pathways within the crust.

Session

Large-scale tectonics