تحلیل داده های سن سنجی زیرکن بر اساس شیمی بلور در مجموعه دگرگونی بنه شورو، خاور ساغند، ایران مرکزی

In this article, metabasic and gneissic rocks of Gelmandeh and Zamanabad mountain (Boneh-Shurow complex, Saghand region) have been used for U-Pb dating. Analyses of zircon crystals yielded concordant U–Pb ages with weighted mean ۲۰۶Pb/۲۳۸U ages of ۵۴۵.۴ ±۳.۶ Ma (MSDW=۱.۷) for garnet amphibolite, ۵۴۱.۲ ± ۴.۴ Ma (MSDW=۱.۸) for metagabbro, ۵۴۱.۳ ±۳.۵ Ma (MSDW=۰.۲۶) for quartz-feldspatic gneiss and ۵۴۹.۲ ± ۲.۶ Ma (MSDW=۰.۲۸) for amphibole- biotite gneiss. The studied zircon crystals has continental, crustal nature and show a strong affinity to magmatic zircons in Chondrite-normalized patterns. The ages that approximately ranges between ۵۴۱-۵۴۹ Ma are interpreted as the Crystalline age of the garnet amphibolite and gneissic parental magma. These ages previously assumed as the timing of peak-metamorphism of the Boneh-Shurow garnet-amphibolite and emplacement ages for the granitic precursor of gneissic rocks.

کلیدواژه ها:

ایران مرکزی ، ساغند ، بنه شورو ، دگرگونی ، زیرکن ، سن سنجی اورانیم-سرب