The first complete scan of the ReesScan fieldsite has now been acquired.  In just over 5 days ArgoScan acquired over 300 individual scans, each extending over a range of 100 m.

 

These scans, each comprising over 20 million xyz survey observations, were tied to the new New Zealand mapping system using precision GPS.

 

The image on the right shows a typical 'point-cloud' generated by each scan.  In this, the survey points are colour coded with a measure of the intensity of the laser return pulse.  This decays with distance from the scanner, but is also closely linked to the reflectivity (albedo) of the surface material.

 

ArgoScan uses a phase-based ranging laser scanner, a Leica HDS6100, which is capable of acquiring over 500,000 points per second!  The resulting scans have a typical point spacing on the ground of less than one centimetre. 

 

Scans of the study reach, 3 x 0.7 km, will be completed after each significant river flow event, and together will make this one of the largest survey datasets ever undertaken.