> Can anyone provide me with a date for the Chicxulub Crater? 64.98 +- 0.05 million years. Dated by the uranium/lead ratio in zircon crystals. > How close was it to the faunal exctinction? Due to lack of zircon crystals, the extinction can't be dated that exactly... the usual date of 65 million years fits the crater age exactly enough, however.