A mid-Palaeozoic basement to the Antarctic Peninsula is confirmed by a geochronological study of the gneissose country rock of the Mesozoic magmatic arc of eastern Graham Land. Rb–Sr whole-rock ages of 410 ± 15 and 426 ± 12 Ma from samples of orthogneiss indicate a previously unrecognized episode of granitic magmatism in the Antarctic Peninsula during the Silurian. Sm–Nd data on garnet–whole-rock pairs indicate that subsequent amphibolite facies metamorphism occurred in late Carboniferous times, probably as a result of plutonism.

This content is PDF only. Please click on the PDF icon to access.

First Page Preview

First page PDF preview
You do not currently have access to this article.