The duration of prograde garnet crystallization in the UHP eclogites at Lago di Cignana, Italy

Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

4

Scientific paper

The distinct core-to-rim zonation of different REEs in garnet in metamorphic rocks, specifically Sm relative to Lu, suggests that Sm-Nd and Lu-Hf isochron ages will record different times along a prograde garnet growth history. Therefore, REE zonations in garnet must be measured in order to correctly interpret the isochron ages in terms of the garnet growth interval, which could span several m.y. New REE profiles, garnet crystal size distributions, and garnet growth modeling, combined with previously published Sm-Nd and Lu-Hf geochronology on a UHP eclogite of the Zermatt-Saas Fee (ZSF) ophiolite, Lago di Cignana (Italy), demonstrate that prograde garnet growth of this sample occurred over a ~ 30 to 40 m.y. interval. Relative to peak metamorphism at 38 to 40 Ma, garnet growth is estimated to have begun at ~ 11 to 14 kbar pressure at ~ 70 to 80 Ma. Although such a protracted garnet growth interval is surprising, this is supported by plate tectonic reconstructions which suggest that subduction of the Liguro-Piemont ocean occurred through slow and oblique convergence. These results demonstrate that REE zonations in garnet, coupled to crystal size distributions, provide a powerful means for understanding prograde metamorphic paths when combined with Sm-Nd and Lu-Hf geochronology.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

The duration of prograde garnet crystallization in the UHP eclogites at Lago di Cignana, Italy does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with The duration of prograde garnet crystallization in the UHP eclogites at Lago di Cignana, Italy, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The duration of prograde garnet crystallization in the UHP eclogites at Lago di Cignana, Italy will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1359352

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.