Palaeomagnetic Investigations on Palaeozoic and Mesozoic Igneous and Metasedimentary Rocks from Northern Victoria Land, Antarctica

C. Rolf¹* & F. Henjes-Kunst²

¹Leibniz Institute for Applied Geosciences (GGA), Stilleweg 2, D-30655 Hannover - Germay
²Bundesanstalt für Geowissenschaften und Rohstoffe, Stilleweg 2, 30655 Hannover - Germany

Received 18 December 2002; accepted in revised form 24 October 2003
 

Abstract - This paper reports on the results of palaeomagnetic investigations in northern Victoria Land, Antarctica (NVL). Rocks of Late Cambrian to Ordovician age (metasedimentary Leap Year Group), of Devonian age (Gallipoli volcanics), of Devonian to early-Carboniferous age (Admiralty Intrusives) and of Jurassic age from the volcanic Ferrar Group were studied. Rocks of the Leap Year Group from one location yield a pole that could be interpreted to indicate a Cretaceous overprint using in-situ directions or an Early Palaeozoic pole using the bedding correction. More sites are needed to determine which interpretation is correct. The survey on the volcanic rocks from Gallipoli Heights differs from similar age poles from other parts of NVL. This could indicate localized vertical axis rotations along faults inferred to have Cenozoic strike-slip motion. Admiralty intrusives at Lillie Marleen hut show chaotic behaviour. No stable directions of the palaeomagnetic field could be determined. The Jurassic dolerites and basalts of the Ferrar Group yield poles far away from the well established Jurassic pole for East Antarctica but close to Cretaceous poles from Marie Byrd Land (West-Antarctica). This fits well with an approximately 100 Ma old hydrothermal alteration of parts of NVL.

 
*Corresponding author (c.rolf@gga-hannover.de)