Representative and whole rock analyses of rocks from Filchnerfjella, Antarctica

• Main Authors: Owada, Masaaki, Baba, Sotaro, Läufer, Andreas, Elvevold, Synnøve, Shiraishi, Kazuyuki, Jacobs, Joachim
• Format: Other/Unknown Material
• Language: English
• Published: PANGAEA 2003
• Subjects: Dronning Maud Land; Antarctica; Filchnerfjella; Priority Programme 1158 Antarctic Research with Comparable Investigations in Arctic Sea Ice Areas; ROCK; Rock sample; SPP1158; Antarc*; Antarctic; East Antarctica; Polar geoscience; Sea ice
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.849089; https://doi.org/10.1594/PANGAEA.849089

The geological history of Filchnerfjella and surrounding areas (2°E to 8°E) in central Dronning Maud Land, East Antarctica, is constructed from metamorphic and igneous petrology, and structural investigations. The geology of Filchner-fjella consists mainly of metamorphic rocks accompanied by intrusive rocks. Two stages of metamorphism can be recognized in this area. The earlier stage metamorphism is defined as a porphyroblast stage (garnet, hornblende, and sillimanite stable), and the later one is recognized as a symplectic stage (orthopyroxene and cordieritestable). Taking metamorphic textures and geothermobarometries into account, the rocks experienced an early high-P/medium-T followed by a low-P and high-T stage. Partial melting took place during the low-P/high-T stage, because probable melt of leucocratic gneiss contains cordierite. The field relationships and petrography of the syenite at Filchnerfjella are similar to those of post-tectonic plutons from central Dronning Maud Land, and most of the post-tectonic intrusive rocks have within-plate geochemical features. The structural history in Filchnerfjella and surrounding areas can be divided into the Pan-African stage and the Meso to Cenozoic stage that relates to the break-up of Gondwana.