COOLING AGE OF THE BIRIMIAN JUVENILE CRUS T IN WEST-AFRICA - U-PB, RB-SR AND K-AR DATA ON THE 2.1 GA GRANITE-GREENSTONE TERRAINS FROM SW NIGER

Authors
CHEILLETZ A BARBEY P LAMA C PONS J ZIMMERMANN JL DAUTEL D
Citation
A. Cheilletz et al., COOLING AGE OF THE BIRIMIAN JUVENILE CRUS T IN WEST-AFRICA - U-PB, RB-SR AND K-AR DATA ON THE 2.1 GA GRANITE-GREENSTONE TERRAINS FROM SW NIGER, Comptes rendus de l'Academie des sciences. Serie II. Mecanique, physique, chimie, astronomie, 319(4), 1994, pp. 435-442
Citations number
15
Categorie Soggetti
Multidisciplinary Sciences
Journal title
Comptes rendus de l'Academie des sciences. Serie II. Mecanique, physique, chimie, astronomie → ACNP
ISSN journal
12518069
Volume
319
Issue
4
Year of publication
1994
Part
2
Pages
435 - 442
Database
ISI
SICI code
1251-8069(1994)319:4<435:CAOTBJ>2.0.ZU;2-0
Abstract
A comparison between zircon U-Pb, whole-rock Rb-Sr and biotite-amphibo le K-Ar data on Birimian granite-greenstone terrains from SW-Niger ind icates that the youngest granitic plutons were emplaced at 2,115+/-5 M a and that both the plutons and the surrounding greenstones yield cool ing ages around 2,118 Ma. The age similarity between the end of the pl utonism and the cooling of plutons and surrounding greenstone further suggests rapid cooling at the end of the plutonic event and, thus, cor roborates a model of greenstone metamorphism linked to the thermal eff ect of the plutons.