Predicting Rock Fall Hazards

The latest laser scanning and remote controlled aircraft technology are to be used to monitor glaciers where unstable slopes and rock falls are a continual threat. A Riegl LMS-Z620 long-range scanner, capable of measuring tiny movements over a 2km range, is being supplied by 3D Laser Mapping for the research by the University of Northumbria. Scan data will be used to help create 3D maps using low-level aerial photographs captured by an Unmanned Aerial Vehicle (UAV).

The laser scanner will be used on a range of projects including the monitoring of retreating glaciers in the European Alps and the investigation of rock falls in the Southern Alps of New Zealand. Selected by the University of Northumbria to enhance research, teaching and Enterprise activity in the School of Applied Sciences, the Riegl LMS-Z620 can obtain 10mm accuracies at distances of up to 2km.

Initially deployed in Europe and New Zealand the scanner will be used to monitor the movement of glaciers and record rock falls and slope failures. By collecting highly accurate measurements on an hour to hour, day to day, week to week basis longer term comparisons can be made and a better understanding of the magnitude and frequency of falls and failures gained. The laser scanner will also be used to support studies in geo-archaeology helping to create virtual representations of sites by providing a base onto which geo-chemical data can be overlaid for interpretation.

"Realistically, long-range terrestrial laser scanning is the only way of capturing this type of data. Daily rock fall events onto glaciers need to be quantified and much ablation (loss of solid material, especially ice, by melting or evaporation) monitoring is crude - often from satellites at long intervals," commented Dr Stuart Dunning, Senior Lecturer in Physical Geography at the University of Northumbria.

The Riegl scanner will also be used to support ongoing research into the use of Unmanned Aerial Vehicles for low level aerial photography of active river systems, using UAVs held by Northumbria University, and in collaboration with Blue River Studios. Data captured by the scanner will be integrated with that captured by the UAV and used to validate and enhance resulting height models. As Crime Sciences and Forensics also form part of the School of Applied Sciences the scanner may be used for mapping both simulated and real crime scenes.

The Riegl LMS-Z620 is a rugged and fully portable sensor including a high performance, long-range 3D scanner, operating and processing software and a calibrated and accurately orientated high-resolution digital camera. The scanner combines a wide field of view, high maximum range - up to 2km - and fast data acquisition with field accuracies of 10mm.