Rb-Sr mineral isochron ages of metamorphic rocks around Syowa Station and from the Yamato Mountains, East Antarctica
Rb-Sr mineral isochron ages were determined for three metamorphic rocks around Syowa Station and from the Yamato Mountains, eastern Queen Maud Land. The Rb-Sr isotopic data demonstrate that the complete Sr isotopic homogenization occurred among K-feldspar, plagioclase, biotite and whole-rock, and de...
Main Authors: | , , |
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Format: | Report |
Language: | English |
Published: |
Geological Survey of Japan/National Institute of Polar Research/National Institute of Polar Research
1985
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Subjects: | |
Online Access: | https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=1791 http://id.nii.ac.jp/1291/00001791/ https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=1791&item_no=1&attribute_id=18&file_no=1 |
Summary: | Rb-Sr mineral isochron ages were determined for three metamorphic rocks around Syowa Station and from the Yamato Mountains, eastern Queen Maud Land. The Rb-Sr isotopic data demonstrate that the complete Sr isotopic homogenization occurred among K-feldspar, plagioclase, biotite and whole-rock, and define isochron ages of 482.5±9.5,468.9±7.8 and 493.3±4.5 Ma for rocks from Syowa Station, Skarvsnes and the Yamato Mountains, respectively. These ages probably represent the time of cooling after the regional metamorphism or granite intrusion. K-Ar age determinations on three metamorphic rocks give biotite and hornblende ages of 469±14,480±15 and 483±15Ma, and 502±15Ma, respectively. |
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