Skip to Main Content
Skip Nav Destination
GEOREF RECORD

3.96 Ga gneisses from the Slave Province, Northwest Territories, Canada; with Suppl. Data 89-17

S. A. Bowring, I. S. Williams and W. Compston
3.96 Ga gneisses from the Slave Province, Northwest Territories, Canada; with Suppl. Data 89-17
Geology (Boulder) (November 1989) 17 (11): 971-975

Abstract

Ion microprobe U-Pb analyses of zircons have identified the Acasta gneisses, from the westernmost Slave province, Canada, as the oldest known intact terrestrial rocks. Zircons from two samples indicate that the tonalitic to granitic protoliths of the gneisses crystallized at 3962 + or -3 Ma, confirming earlier indications, from conventional zircon and Nd analyses, of the rock's antiquity. The U-Pb analyses indicate that in addition to recent Pb loss, the zircons underwent an early episode of Pb loss and that new zircons crystallized ca. 3.6 Ga. The gneisses were derived from a source that had a long-lived enrichment in light REE, possibly from even older rocks that may be present in the Slave province.


ISSN: 0091-7613
EISSN: 1943-2682
Coden: GLGYBA
Serial Title: Geology (Boulder)
Serial Volume: 17
Serial Issue: 11
Title: 3.96 Ga gneisses from the Slave Province, Northwest Territories, Canada; with Suppl. Data 89-17
Affiliation: Wash. Univ., Dep. Earth and Planet. Sci., St. Louis, MO, United States
Pages: 971-975
Published: 198911
Text Language: English
Publisher: Geological Society of America (GSA), Boulder, CO, United States
References: 18
Accession Number: 1989-074220
Categories: GeochronologyIgneous and metamorphic petrology
Document Type: Serial
Bibliographic Level: Analytic
Illustration Description: illus. incl. geol. sketch map
N60°00'00" - N84°00'00", W136°00'00" - W102°00'00"
N62°00'00" - N69°00'00", W117°00'00" - W105°00'00"
Secondary Affiliation: Aust. Natl. Univ., AUS, Australia
Country of Publication: United States
Secondary Affiliation: GeoRef, Copyright 2017, American Geosciences Institute.
Update Code: 1989
Close Modal

or Create an Account

Close Modal
Close Modal