GeoSolutions Consulting Inc. 38 Auriga Drive, Unit #3 Ottawa, ON, K2E 8A5 www.geosolutions.com Understanding the Frank Landslide Through GIS and 3D Models In the southwestern corner of Alberta just east of the Crowsnest Pass, lies the small town of Frank, Alberta. In 1903 this was a small coal mining community of about 600 people that became known to the world as the site of Canada’s worst natural disaster. In the early morning hours of April 29, 1903, Turtle Mountain collapsed, resulting in the most deadly landslide in Canadian history. In 100 seconds, at least 76 people were buried alive under 82 million metric tonnes of massive limestone boulders. The dimensions of the rock mass was enormous, measuring about 150 metres deep, 640 metres high and 1 kilometre wide. As it fanned out over a distance of over 700 metres, it crushed the homes in the south- eastern portion of Frank; buried over 1.5 kilometres of the Canadian Pacific Railroad; and turned a river into a lake. The magnitude of the event was beyond what anyone could have imagined. Tails of broken limestone spread far across the valley deeply burying houses, roads and the railroad with as much as 30 metres of rock and rubble. One spur of material followed the banks of the Gold Creek pushing a wall of water and mud in front of it and smashing through all the buildings across the creek from Frank. Of the 76 known and listed dead, only 12 bodies were ever recovered. The primary cause of the Frank Slide was the unstable geological structure of Turtle Mountain. Other contributing factors may also have been underground coal mining, water action in the cracks of the summit and severe weather conditions. The physical mechanism that enabled this landslide to spread over 3 square kilometres in less that 100 seconds has been the subject of much discussion and speculation. It is believed that a compressed layer of air between the debris and the ground may have aided the spread. The Frank Slide Interpretative Centre has the task of explaining what occurred to thousands of visitors each year. This task is made easier with the use of a large physical model that is constructed using modern technologies that use GIS. Through the use of GIS software, high resolution DEM and imagery, GeoSolutions Consulting is able to create 3D products that are impressive and educational. Frank slide, April 29, 1903. Eighty-two million metric tonnes of rock slid down Turtle Mountain in less than 100 seconds. Seventy- six people died. © Geological Survey of Canada This high-density foam model of the Frank Slide measures about 160 cm long x 70 cm wide x 50 cm high.