"Initially the blast uses up all nearby O2 (oxygen), vaporizing or melting everything. When the atmospheric oxygen does finally rush back in (@15 min later) every organic compound ignites spontaneously creating another smaller explosion contained within the mushroom cloud. The ground blast pattern yielded resembles that of a daisy shaped cookie cutter."
"Everything within a ~600 yard radius, 1200 yard diameter, is incinerated; all protoplasm(the colorless liquid or colloidal contents of a living cell) within a 1 mile radius, 2 mile diameter, is essentially pulverized by the extreme overpressure, which requires that the bomb be dropped from a special operations C-130 Hercules from at least 6000 feet."