Ages of detrital zircon grains from Neoproterozoic siliciclastic rocks in the Shakawe area: implications for the evolution of Proterozoic crust in northern Botswana

Citation
Rbm. Mapeo et al., Ages of detrital zircon grains from Neoproterozoic siliciclastic rocks in the Shakawe area: implications for the evolution of Proterozoic crust in northern Botswana, S AFR J GEO, 103(2), 2000, pp. 156-161
Citations number
28
Categorie Soggetti
Earth Sciences
Journal title
SOUTH AFRICAN JOURNAL OF GEOLOGY
ISSN journal
10120750 → ACNP
Volume
103
Issue
2
Year of publication
2000
Pages
156 - 161
Database
ISI
SICI code
1012-0750(200003)103:2<156:AODZGF>2.0.ZU;2-3
Abstract
The Precambrian rocks of northern Botswana comprise poorly exposed igneous complexes, high-grade metamorphic rocks, as well as sedimentary sequences i ncluding mainly siliciclastic and carbonate rocks. New U-Pb SHRIMP data are presented for detrital zircons from siliciclastic rocks collected from the Shakawe area in northern Botswana. These data show three main age groups a t c. 1020 Ma, 1090 Ma, and 2050 Ma which support contentions for local prov enance of the sediments. They also fix the maximum age of the deposition of these siliciclastic rocks at 1020 Ma. The results support field evidence s uggesting that the siliciclastic rocks exposed in the Shakawe zone are part of the Ghanzi-Chobe Supergroup.