Named in honor of Glen A. Izett, an American geologist of many talents. Izett has carried out the most detailed studies of the Cretaceous-Tertiary boundary clay layers in the western United States and their implications for the great impact event that terminated the Cretaceous. He has also contributed the most precise determinations of ages of tektites from the extensive Australasian strewn field. His work with John Obradovich on the ages of volcanic ashes and tektites has led to the most highly refined time scale for the reversals of the geomagnetic field in the late Quaternary. (M 29671) _ _.