Topographic Differencing

Topographic differencing reveals surface change from a variety of tectonic, geomorphic, and anthropogenic processes including earthquakes, volcanic eruptions, river erosion, landslides, sand dune migration, and urban development. Differencing techniques have grown in popularity over the past decade as the number of multi-temporal topographic datasets has increased. Below, we present resources that we have developed on topographic differencing.

Bridge
Vertical differencing showing sand dune migration in New Mexico.  

Peer-reviewed publications
GitHub Code Repositories:
Blog posts
Video tutorials
Differencing Workshop:
Undergraduate Topographic Differencing Exercise:

In this undergraduate-oriented exercise, students are geologists working for the United States Geological Survey (USGS) and must respond to a recent pretend but realistic earthquake along the Wasatch Fault. They aid in the response by mapping the surface rupture and calculating the surface displacement, coseismic slip, and earthquake magnitude from lidar topography acquired before and after the earthquake. The exercise is available here.