I just finished reading a great book on avalanches call Snowstruck by Jill Fredston. The force and speed are remarkable even when it is only a 2-3 foot thick chunk cleaved off a slope. The snow can become as dense as concrete in some of the snowfields left after the avalanche, due to load and probably do to a friction related compaction during the avalanche. There can be a preceding "blow" in advance of the snowfront that can level buildings and trees. She alleges that some avalanches move at 200 mph. (The physics of that puzzles me.)
The cure for a fallacious argument is a better argument, not the suppression of ideas.
-- Carl Sagan