NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Platinum group nuggets in deep sea sedimentsThe existence of iron meteor oblation spheres in deep sea sediments was known for over a century. These spheres generally were believed to be composed of either pure magnetite and wustite or an oxide shell surrounding a NiFe metal core. A large number of 300 micron to 600 micron spheres found were pure oxide spheres, usually containing a solitary 10 micron platinum group nugget (pgn) composed almost entirely of group VIII metals. Twelve PGN's were analyzed and most had chondritic abundances with some depletions that correlate with element volatility. PGN formation by oxidation of a molten metal sphere entering the atmosphere cannot occur if the oxygen abundance in the atmosphere is less than half of its present value. The first appearance of PGN's in the geological record should mark when, in the Earth's history, oxygen rose to this level.
Document ID
19850007302
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Brownlee, D. E.
(Washington Univ. Seattle, WA, United States)
Bates, B. A.
(Washington Univ. Seattle, WA, United States)
Wheelock, M. M.
(Washington Univ. Seattle, WA, United States)
Date Acquired
August 12, 2013
Publication Date
January 1, 1984
Publication Information
Publication: Lunar and Planetary Institute The 47th Ann. Meteoritical Soc. Meeting
Subject Category
Lunar And Planetary Exploration
Accession Number
85N15611
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

Available Downloads

There are no available downloads for this record.
No Preview Available