A fir born before the Tunguska catastrophe.
Up to the Tunguska event, the growth rings of this fir increase regularly in all the directions giving rise to a nearly circular pattern. From the Tunguska catastrophe, we observe an accelerated growth and an asymmetry with a greater enhancement of the rings in the direction of their leaning. This phenomenom was studied in papers ,  and  (Russian).
Back to the Tunguska Home Page