Calculating Stalagmite Creation Feats

[Arrogant_Schmuck]

You might be familiar with these. When a character punches or hits the ground so hard that it produces several stalagmites.

Here's a great example: https://www.youtube.com/watch?v=c-a3vnLbFnw&t=661s

Any ideas as to how one might calculate the destructive potential in these? I can't find any examples of past calcs like this.