Disputation and trial lecture: Øyvind Sunde
Øyvind Sunde at the Natural History Museum will be defending the thesis "Mineralogy and geochemistry of pegmatites in the Larvik Plutonic Complex, Norway" for the degree of PhD.
Time: Friday 27 September at 10:15
Place: Tøyen Hovedgård
The candidate will give a trial lecture on the given topic:
Mineralisation associated with pegmatites
- Professor Frances Wall, University of Exeter, United Kingdom
- Dr. Erik Jonsson, Sveriges Geologiska Undersökning, Sverige
- Professor Hans Arne Nakrem, Natural History museum, University of Oslo
- Associate professor Henrik Friis, Natural History Museum (University of Oslo)
- Professor Tom Andersen, Department of Geosciences
Chair of defence
Short presentation of the thesis
Peculiar rocks consisting of large and rare minerals are known as nepheline syenite pegmatites and can be found in larvikite (national rock of Norway!) around the Larvik area. Detailed chemical analyses of a mineral called wöhlerite, which is rare on the global scale but common in the pegmatites, reveal a close relationship of the pegmatites to the host larvikite. These pegmatites have a unique internal structure of mineral distribution, and may be distinguished based on their mineral assemblages. Boron isotopic composition of tourmaline and hambergite reveal that external fluids have interacted with the early melt. Such boron isotope data is particular interesting for the research community, because they represent a unique geochemical system where boron isotopes are poorly studied. Furthermore, this study developed hambergite as a new host for boron isotopes.
Studies of how these pegmatites form is important scientifically to develop our understanding of these geological systems, and commercially because this group of rocks are potential sources for important strategic elements.