| Title | Early Cambrian crustal shortening and a clockwise P-T-t path from the southern Prince Charles Mountains, East Antarctica; implications for the formation of Gondwana |
| Author | Boger, S.D.; Wilson, C.J.L. |
| Author Affil | Boger, S.D., University of Melbourne, School of Earth Sciences, Melbourne, Victoria, Australia |
| Source | Journal of Metamorphic Geology, 23(7), p.603-623, . Publisher: Blackwell, Oxford, United Kingdom. ISSN: 0263- 4929 |
| Publication Date | Sept. 2005 |
| Notes | In English. 81 refs. GeoRef Acc. No: 288102 |
| Index Terms | Antarctica--East Antarctica; Antarctica--Prince Charles Mountains; amphibolite facies; Antarctica; Cambrian; crustal shortening; East Antarctica; facies; Gondwana; Lambert Province; Lower Cambrian; Mac Robertson Land; Mawson Escarpment; metamorphic rocks; metapelite; metasedimentary rocks; P-T conditions; P-T-t paths; Paleozoic; Pan-African Orogeny; petrography; plate collision; plate tectonics; Prince Charles Mountains; X-ray data |
| Abstract | Cambrian orogenesis (550-490 Ma) in the Lambert Province of the southern Prince Charles Mountains resulted in three successive stages of deformation. The earliest of these deformations resulted in the development of a layer-parallel foliation (S1) that was folded into macro-scale recumbent folds (F2). Subsequent deformation buckled the rocks into long-wavelength (c. 20 km), SW- to NW-trending antiformal closures (F3) mostly separated from each other by west to SW trending, steeply dipping, high-strain zones. Metapelitic rocks from the region are divisible into two compositional types: a high-Al, -Fe and -K type and a high-Mg, -Ca and -Na type. In rocks of both composition, relic staurolite preceded the formation of upper amphibolite facies garnet + biotite + sillimanite ± muscovite mineral assemblages that record peak pressures and temperatures of c. 650-700 °C and 6-7 kbar. Subsequent decompression of c. 3 kbar is implied from texturally late plagioclase and a reduction in the modal abundance of garnet in the high- Al, -Fe and -K metapelites, and from texturally late cordierite in the more magnesium rocks. (mod. journ. abst.) |
| Publication Type | journal article |
| Record ID | 85029 |