Dear colleagues,
Does anyone has any thoughts about the origin and P-T-t significance of
lamellar intergrowths of Ilmenite(?)-Corundum-Hercynite? I found these in
plagioclase-biotite schlieren in a Neoarchaean metadiorite SW of Murmansk.
The corundum occurs as lamellae/laths in an opaque mineral (ilmenite?) and
the bottle-green hercynite is present as rims on the ilmenite, or occurs as
individual grains.
The only refs I know of are Coolen (1980) from a granulite-facies calc-
silicate, and who suggests they pseudomorph hoegbomite (p.49). The other
one is Swap & Onstott (1989)who describe them from a Cpx-Opx-Hbl metagabbro.
Coolen, J.J.M.M.M., 1980. Chemical petrology of the Furua granulite
complex, southern Tanzania. Ph.D. thesis Univ. of Amsterdam.
Swap & Onstott, 1980. Precam. res. 42, 293-314.
Tanks in advance,
Martin Timmerman
School of Earth Sciences
Leeds University
Leeds LS2 9JT
England
Tel.: +113-233 6623
Fax: +113-233 5259
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