Microtektites in Deep-sea Sediments

Abstract

AN examination of deep-sea sediments deposited south of Australia and Sumatra during and after the last polarity reversal of the Earth's magnetic field resulted in the discovery of a zone containing microscopic (< 1 mm) glassy objects. (Five to ten gram samples were washed through a 125µ sieve.) This zone, which occurs immediately above the last geomagnetic reversal, has now been found in five cores from the Australia Basin, one from the Wharton Basin, and one from the Philippine Basin. Two of these cores will be discussed in a later publication (RC 9–142, 42° 42′ S., 116° 52′ E., depth 2,290 fathoms, from the Australia Basin, and V 20–138, 28° 52′ N., 135° 33′ E., depth 2,264 fathoms, from the Philippine Sea).