Terrestrial Laser Scanning (TLS)

UNAVCO maintains a pool of Terrestrial Laser Scanning (TLS) instruments and associated peripherals, digital photography equipment, software and ancillary equipment optimized to support Earth science investigators.


Researchers interested in TLS are encouraged to contact UNAVCO for additional information regarding project planning, proposal preparation, instrumentation and engineering support, and other services currently under development. Support may be requested from the UNAVCO On-line Support Request Form.

Photo (left) of UNAVCO TLS instrument (Riegl VZ-400) being operated by Professor Guoquan Wang and student Arlenys Ramiriz (University of Puerto Rico at Mayaguez) and TLS derived 3D point cloud (right) of a rapidly deforming landslide in El Yunque National Forest, Puerto Rico. For more information please see the project highlight.

TLS technology is based on Light Detection and Ranging (LiDAR) and is also referred to as ground-based LiDAR or tripod LiDAR. It is an active imaging system whereby laser pulses are emitted by the scanner and observables include the range and intensity of pulse returns reflected by the surface or object being scanned. Some instruments are capable of measuring multiple returns or even the full waveform of the reflected pulse. LiDAR measurements, combined with the orientation and position of the scanner, produce a 3-dimensional “point cloud” dataset. The primary capability of TLS is the generation of high resolution 3D maps and images of surfaces and objects over scales of meters to kilometers with centimeter to sub-centimeter precision. This allows for high accuracy mapping as well as the determination of surface changes over time via repeat measurements.

TLS is a powerful geodetic imaging tool ideal for supporting a wide spectrum of user applications in many different environments. Geoscience applications to date include detailed mapping of fault scarps, geologic outcrops, fault-surface roughness, frost polygons, lava lakes, dikes, fissures, glaciers, columnar joints and hillside drainages. Repeat TLS surveys allow the imaging and measurement of surface changes through time due, for example, to surface processes, volcanic deformation, ice flow, beach morphology transitions, and post-seismic slip. The incorporation of GPS measurements provides accurate georeferencing of TLS data in an absolute reference frame. The addition of digital photography yields photorealistic 3D images. It has been demonstrated that TLS derived 3D imagery is a unique and powerful tool for educational and outreach applications as well.

Photo (left), TLS LiDAR point cloud colored by height (middle) and TLS derived 3D surface model (right) of the precariously balanced rock (PBR) at Echo Cliffs in southern California. Courtesy K. Hudnut, G. Bawden and S. Bond (USGS). For more information please see the project highlight.

Last modified Wednesday, 08-Aug-2012 20:20:02 UTC