Geomorphic Unit Tool Documentation



Welcome to PyGUT website. This site provides documentation for the Geomorphic Unit Tool (GUT). The tool delineates instream geomorphic units (GUs) from topography using a 3-tiered hierarchical classification adapted from (Wheaton et al., 2015).

We provide documentation on:

  1. Theoretical background underpinning the tool
  2. Example applications
  3. How to run GUT
  4. Descriptions of GUT output
  5. The nuts and bolts behind the algorithms

The website is still under construction but will be fully populated shortly. In the meantime, if you have questions or want to run the code, please contact Sara Bangen ( or Natalie Kramer (


Sara Bangen, Natalie Kramer, and Joe Wheaton of Utah State University’s Ecogeomorphology & Topographic Analysis Lab


If you are wishing to run the latest release of pyGUT, you can download the python scripts and associated Arc files here from GitHub.

Source Code

For those wishing to tweak the source code and/or documentaton, the open source version of pyGUT is available in the pyGUT repo on GitHub.


GUT is designed to run in Python and currently has ESRI dependencies. Users need to have ArcMap 10.1 or greater along with Spatial Analyst and 3D Analyst extensions. In the future, we plan to code GUT in an open source language.

Presentations & Publications

  • Kramer N, Bangen SG, Wheaton JM, Bouwes N, Wall E, Saunders C, and Bennett S.. 2017. Geomorphic Unit Tool (GUT): Applications in Fluvial Mapping. EP11A-1546. AGU. New Orleans, LA, 11-15 Dec. DOI: 10.13140/RG.2.2.30142.18241
  • Bangen SG, Kramer N, Wheaton, JM, and Bouwes N. 2017. The GUTs of the Geomorphic Unit Tool: What is under the hood. EP31D-1901. AGU. New Orleans, LA, 11-15 Dec. DOI: 10.13140/RG.2.2.31118.66884
  • Bangen SG, Kramer N, Wheaton JM, and Bouwes N. In Preparation. Mapping instream geomorphic units from high resolution topography.