EVIDENCE FOR THE EXTREME AGE OF CERTAIN MINERALS FROM THE DOMINION REEF CONGLOMERATES AND THE UNDERLYING GRANITE IN THE WESTERN TRANSVAAL

Journal Article · Mon Jan 01 04:00:00 EST 1962 · Geochim. et Cosmochim. Acta

DOI:https://doi.org/10.1016/0016-7037(62)90003-0· OSTI ID:4796633

Nicolaysen, L O; Burger, A J; Liebenberg, W R

Isotopic composition of galenas from the Witwatersrand indicated the existence of a hypothetical parent uraninite in this region; it was surmised to have originally crystallized ~3000 million years ago, and to have suffered alteration and expulsion of radiogenic lead later in its history. New age data are presented here for samples of total rock, and purified detrital monazite, from the Dominion Reef conglomerates which lie below the Witwatersrand System. These data give very strong evidence that radioactive minerals in the Dominion Reef have an age of crystallization close to 3100 million years. They are probably the oldest well-dated radioactive minerals. The analysis of total rock samples appears to be an important approach to the study of uranium minerals in ancient conglomerates. Clearcut evidence concerning the time of deposition of the Dominion Reef conglomerate is still lacking. (auth)

• Research Organization: Originating Research Org. not identified
• NSA Number: NSA-16-013377
• OSTI ID: 4796633
• Journal Information: Geochim. et Cosmochim. Acta, Journal Name: Geochim. et Cosmochim. Acta Vol. Vol: 26
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

AGE ESTIMATION
CONGLOMERATES
CRYSTALLIZATION
DECAY
DECOMPOSITION
DEPOSITS
DISTRIBUTION
GALENA
GEOCHEMISTRY
GEOLOGY, MINERALOGY, AND METEOROLOGY
GRANITES
IMPURITIES
LEAD
LEAD ISOTOPES
LEAD SULFIDES
MINERALS
MONAZITES
RADIOACTIVITY
ROCKS
SOUTH AFRICA
URANINITES
URANIUM MINERALS