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The Black Lake rockslide is located on the east wall of an open-pit mine initially operated by LAB Chrysotile near Thetford Mines, Quebec. Movements were observed in July 2012 when a volume of 2.0 × 107 m3 was mobilized, destroying a large portion of Highway 112. Mining operations ceased in 2012, causing the complete shutdown of the pumping system whose goal was to prevent the rise of water level in the pit. As the water level increases in the pit, it is essential to determine the potential of tsunami generation by possible partially submerged rockslides and to understand the potential impacts. A series of possible scenarios have been analysed with regard to velocity and acceleration of the potential rockslide as well as the corresponding wave generation and inundation. Results from the simulation show that when the factor of safety of the global slope is less than unity, inundation would not reach the potentially vulnerable infrastructures. Maximum wave height will vary as a function of the filling of the lake, and the lower wave height relative to water depth will happen when the lake is completely filled. [ABSTRACT FROM AUTHOR]

Abstract: This paper deals with the development of the morphology in polyethylene glycol (PEG) and polyamide 66 (PA66) immiscible blends exhibiting an extremely low viscosity ratio . These materials were obtained by melt mixing, under different operating conditions, using a twin-screw batch-type DSM mini-extruder. Scanning electron microscopy, followed by quantitative image analysis was used to determine PEG particles size distribution (PSD) as a function of blends composition and screw rotation speed. Experiments carried out with two mixing time (5 and 10min) showed no significant difference of PSD. So, to avoid thermal degradation of the products, the mixing time was set up at 5min for all experiments. The influence of PEG concentration and screw rotation speed on PSD appeared to be similar to that obtained in a previous study for the same blends elaborated in a Haake internal mixer. The results clearly showed that the average particle diameters decreased as screw rotation speed increased and as PEG concentration decreased. However, this decrease is less important using the twin-screw batch-type mini-extruder with which the particle sizes are smaller. The particles sizes were then correlated to blend composition, shear rate and viscosity ratio owing to an extension of Serpe''s model. The unknown parameters of the corresponding model were estimated on the basis of experimental data. This enabled then to predict with a good precision the influence of the process operating conditions on the morphology of the dispersed phase. [Copyright &y& Elsevier]