Large megacryometeor to tunguska popping like ice cubes in a glass drink it would give the extra velocity to cause a tunguska meteor explosion. Falling megacryometeor to earth alone wouldn't cause the tunguska explosion but if one was to explode on its way to earth it may cause such damage like the june 30th 1908 tunguska explosion in siberia.
And it being about summer-time at the time of the warm weather would contribute to the megacryometeor exploding in mid air while on its way to tunguska, this kind of megacryometeor explosion would be enough force to rip the bark and branches off trees as reported at the epicentre of the tunguska incident.
Referance to Theory
- Keith ranville