On April 29, 1903 at 4:10 a.m., a mass of limestone rock estimated to weigh 82 million tonnes (8.2 x 1010 kg) failed on the flank of Turtle Mountain near the community of Frank, Alberta. The rockslide was initiated at an elevation of 2300 metres above sea level (a.s.l.). The rock mass crashed onto the valley floor at an elevation of 1600 metres a.s.l. and came to an abrupt halt on the opposite valley wall at an elevation of 1800 metres a.s.l. It took only 90 seconds for the rock mass to travel 1.5 kilometres (km) and to cover an area of 3 km2 to a depth of more than 30 metres (m). This is Canada's deadliest rockslide; a portion of the community of Frank was buried by the rock debris and more than 70 fatalities were reported (https://publications.gc.ca/collections/collection_2008/nrcan/M4-59-2- 2008E.pdf). Please view the YouTube video titled "1903: 90 seconds of terror" produced by the Canadian Broadcasting Corporation in 2003 before proceeding to complete this exercise (https://www.youtube.com/watch?v=M2fDOdNzX_U). As the rock mass moved down the mountainside, its potential energy was converted into kinetic energy. What force was applied to this moving rock mass?

GEOG 120 Introduction to Global Environmental Systems Lab Exercise #4 Landslide Hazard Analysis 7 F = m x g Where F = force m = mass of rock (kilograms, kg) g = acceleration due to gravity = 9.8 m/s2

Compute the force applied to the moving rock mass? Work is a measure of the energy transferred by a force on the rock mass. How much work was performed by the moving rock mass? W = F x d Where F = force d = distance (metres, m) Compute the quantity of work performed by the moving rock mass. The unit of measurement for work is a Joule (J): 1 Joule is equal to the amount of work done when a force of 1 Newton displaces a mass through a distance of 1 metre in the direction of the applied force. Power is a measure of the rate of work or a rate at which energy is supplied. How much power was generated by the moving rock mass? P = W/t Where P = power t = time (seconds, s)

11. Compute the power generated by the moving rock mass. The unit of measurement for power is a Watt (W); 1 Watt is equal to one Joule per second.

Compare this result with the rate of electrical power consumption in Canada in 2021 calculated at 14.6 million Watts (14.6 x 106 Watts). The power generated by this single mass movement event is much greater than the annual electrical power consumption in Canada and speaks to the power of earth processes to shape the surface of the Earth.