Stalagmites in ice. How does it happen?

[janger]

I'm new here so I hope I posted this to the correct forum.

 

My brother put some iceblock trays in the freezer one night. The next day he was surprised to find this in the tray. How does this occur? The front "stalagmite" contains bubbles, and we were thinking that has something to do with the formation. But I would really like to know the definite reason as to why this happened.

 

Thanks,

Dave

[janger]

I found the answer

http://www.its.caltech.edu/~atomic/snowcrystals/icespikes/icespikes.htm