TLS Applications for Precarious Rock Research

The following is a guide to using a terrestrial laser scanner (TLS) to scan PBRs in the field (it's still a work in progress):
Documentation for the analysis of the Granite Dells PBR site using TLS

We borrowed a Riegl LPM 800i (LPM 321) terrestrial laser scanner from our colleagues at the UT Dallas Cybermapping Laboratory to scan a ~1.5 m tall by ~1 m wide PBR in the Granite Dells precarious rock zone, central Arizona. The PBR was scanned from six positions, and the scans were aligned to a point cloud totaling 3.4M points.
Here are some photos and screenshots:

We also scanned a ~50 m by ~150 m area covering PBR hillslopes from five scan positions. The resulting 5.5M points were used to create a digital terrain model of precarious rocks and their hillslopes.

Here are some photos, screen shots, and a 5 cm DEM produced using the GEON LiDAR Workflow (

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Page maintained by: David Haddad.
Last modified: January 13, 2009.