Accession Number:

ADA159030

Title:

High Noble Metal Concentrations in a Late Pliocene Sediment,

Descriptive Note:

Corporate Author:

CALIFORNIA UNIV LOS ANGELES

Personal Author(s):

Report Date:

1981-07-30

Pagination or Media Count:

3.0

Abstract:

A 2.3-Myr-old layer in a sediment from the Antarctic Ocean contains Ir and Au at levels comparable with those at the Cretaceous-Tertiary boundary. A sizable fraction of the noble metals is contained in vesicular, millimetre-sized polymineralic grains that closely resemble ablation debris from chondritic meteorites, and there is little doubt that the noble metals resulted from the accretion of a large extraterrestrial object. No massive extinctions or other evidence of environmental stress seem to be associated with this accretionary event.

Subject Categories:

  • Astrophysics
  • Physical and Dynamic Oceanography
  • Geology, Geochemistry and Mineralogy

Distribution Statement:

APPROVED FOR PUBLIC RELEASE