U-Pb zircon, monazite and xenotime geochronology of cordierite-anthophyllite and felsic volcanic rocks in Orijärvi, southern Finland
Bo Johanson; Teemu Vehkamäki; Yann Lahaye; Markku Väisänen; Matti Kurhila
U-Pb zircon, monazite and xenotime geochronology of cordierite-anthophyllite and felsic volcanic rocks in Orijärvi, southern Finland
Bo Johanson
Teemu Vehkamäki
Yann Lahaye
Markku Väisänen
Matti Kurhila
Institute of Seismology, University of Helsinki
Julkaisun pysyvä osoite on:
https://urn.fi/URN:NBN:fi-fe2021042720028
https://urn.fi/URN:NBN:fi-fe2021042720028
Tiivistelmä
We sampled one felsic volcanic rock from the lower part of the Kisko formation and two cordierite-anthophyllite rocks from Orijärvi and Iilijärvi for U-Pb dating. The felsic volcanic rock yield a zircon 207Pb/206Pb weighted average age of ~1.89 Ga. The oldest zircons from the Orijärvi cordierite-anthophyllite rock give a weighted average age of ~1.89 Ga. The monazite from the same sample yield a concordia age of ~1.80 Ga and the xenotime yield a concordia age of ~1.82 Ga. The Iilijärvi cordierite-anthophyllite rock gives a monazite concordia age of ~1.82 Ga. This implies that two metamorphic pulses are recorded in the samples.
Kokoelmat
- Rinnakkaistallenteet [19207]