Preliminary result fot the Rb-Sr mineral isochron ages of granitic rocks from Cape Omega and Oku-iwa Rock, Prince Olav Coast, East Antarctica

The granitic rocks of the Cape Omega, and Oku-iwa Rock, yield the age of 439.0±12.3 Ma with an initial Sr isotope ratio of 0.70609±0.00014 and 417.9±2.2 Ma with an initial Sr isotope ratio of 0.70646+0.00002, respectively. These ages represent the time when these granitic rocks cooled down to the cl...

Full description

Bibliographic Details
Main Authors: Naoko Nishi, Yoshinobu Kawano, Hiroo Kagami
Format: Report
Language:English
Published: Graduate School of Education, Saga University 1999
Subjects:
Rb-Sr mineral age
cooling rate
Cape Omega
Oku-iwa Rock
Liitzow-Holm Complex
East Antarctica
Prince Olav Coast
Oku-iwa
Antarc*
Antarctica
Polar geoscience
Online Access:https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=3048
http://id.nii.ac.jp/1291/00003048/
https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=3048&item_no=1&attribute_id=18&file_no=1
Description
Summary:The granitic rocks of the Cape Omega, and Oku-iwa Rock, yield the age of 439.0±12.3 Ma with an initial Sr isotope ratio of 0.70609±0.00014 and 417.9±2.2 Ma with an initial Sr isotope ratio of 0.70646+0.00002, respectively. These ages represent the time when these granitic rocks cooled down to the closure temperature of biotite and are consistent with previous reported K-Ar biotite ages (339-449 Ma) of granitic rocks in the Liitzow-Holm Complex. Calculated cooling rates of the Cape Omega and the Oku-iwa Rock areas are 5.3-4.1°C/Ma and 3.8-3.6°C/Ma, respectively. These results are consistent with cooling rates for the amphibolite facies terrain of the Liitzow-Holm Complex previously reported.

Similar Items