Last modified on 13 July 2011, at 12:32

K-T boundary

EnglishEdit

Alternative formsEdit

NounEdit

K-T boundary (uncountable)

  1. The geological signature of the transition between the Cretaceous period and the Tertiary period 65.5 million years ago.
    This transition is marked worldwide by a layer of material that contains a high level of iridium.

See alsoEdit