Comment to discussion on graphite in siliciclastic Precambrian graphitic rocks. All the red coloured rocks in the map from Central Lapland in Finland are actually metamorphic graphite rich silicoclastics. The map is airborne electromagnetic real component and the grade of metamorphism varies from low-greenschist (300 oC) in the center to granulite (>850 oC) in the upper (northern) part of the map. There are numerous papers which handle graphite in these rocks (e.g. Korja, T., Tuisku, P., Pernu, T. & Karhu, J. (1996) Field, petrophysical and carbon isotope studies on the Lapland Granulite Belt: implications for deep continental crust. Terra Nova, 8, 48-58.). The map may be compiled from public data at:
http://geomaps2.gtk.fi/activemap/
Regards
Pekka Tuisku
Oulu Mining School
University of Oulu
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