خلال الخمسين مليون سنة تحوَّلت هذه الأشجار إلى ترسُبات هائلة من الفحم و في وقت حدوث هذا
During the intervening 50 million years, those trees had turned into immense deposits of coal, and as it happened, one of the world's largest accumulations of coal was buried right there in Siberia.