Structural Geology of the Robertson Bay and Millen Terranes, Northern Victoria Land, Antarctica
- Edmund Stump
Published Online: 16 MAR 2013
Copyright 1986 by the American Geophysical Union.
Geological Investigations in Northern Victoria Land
How to Cite
Findlay, R. H. (1986) Structural Geology of the Robertson Bay and Millen Terranes, Northern Victoria Land, Antarctica, in Geological Investigations in Northern Victoria Land (ed E. Stump), American Geophysical Union, Washington, D. C.. doi: 10.1002/9781118664957.ch5
- Published Online: 16 MAR 2013
- Published Print: 1 JAN 1986
Print ISBN: 9780875901978
Online ISBN: 9781118664957
- Geology—Antarctic regions—Victoria Land
The structural geology and history of the Robertson Bay and Millen terranes are described and compared with recent structural and geochronological studies elsewhere in northern Victoria Land. One phase of upright folding (RF1) occurs throughout the Robertson Bay terrane, producing an axial plane cleavage (RS1) that intensifies to the southwest. A later deformation produced shortening normal to RS1. Three phases of folding occur in the Millen terrane. The synmetamorphic first event produced isoclinal folds (MF1) and an axial plane schistosity (MS1); the second event produced upright, open folds (MF1) with an axial plane crenulation cleavage (MS2). MF3 is represented by kinks related to younger faults. RF1 and MF1 are contemporaneous at 510±15 m.y. B.P. and may have developed during large-scale westward thrusting. MF2 and the shortening across the Robertson Bay terrane followed the first deformation, in response to west-over-east reverse faulting.