Alvarez, L.W., et al., Extraterrestrial Cause for the Cretaceous-Tertiary Extinction, Science, Volume 208, Number 4448, Pages 1095-1108, Jun 1980
Siegel, E., What Wiped Out the Dinosaurs?, Apr 2009
This thin layer of ash -- the boundary between light and dark in the above picture -- is the split between when dinosaurs are found and when they aren't. What's amazing about this is that this tiny, thin film of a layer contains something in great abundance that the Earth doesn't have much of at all: the element iridium. Naturally, the Earth has so little iridium that it's inconceivable that this iridium could have come from Earth. Where could it have come from?
Iridium is a naturally occurring, extremely heavy, if rare element. As I understand it, massive electrical discharges may forge many exotic elements. Many of these will decay after a few years. Iridium is only one that is found in this layer, but is the smoking gun that there was an event, a CATASTROPHE!
ReplyDeleteThe type of discharge may have resulted in the formation of elements that decayed to iridium adding to the iridium formed in the event.
Or the tooth fairy sprinkled it there over many millenia cos she is a bad bitch....