Clay Mineralogy of the Cretaceous-Tertiary Boundary Clay

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Science  04 Feb 1983:
Vol. 219, Issue 4584, pp. 495-498
DOI: 10.1126/science.219.4584.495


Analyses of the clay mineralogy of samples from the Cretaceous-Tertiary boundary layer at four localities show that the boundary clay is neither mineralogically exotic nor distinct from locally derived clays above and below the boundary. The significant ejecta component in the clay that is predicted by the asteroid-impact scenario was not detected.