Cenozoic metamorphism along the Shan scarp (Myanmar): evidences for ductile shear along the Sagaing fault or the northward migration of the eastern Himalayan syntaxis?

被引：77

作者：

Bertrand, G

Rangin, C

Maluski, H

Han, TA

Thein, M

Myint, O

Maw, W

Lwin, S

机构：

[1] ENS, Geol Lab, CNRS UMR 8538, F-75005 Paris, France

[2] Univ Montpellier 2, Lab Geochronol, CNRS UMR 5567, F-34095 Montpellier, France

[3] Mandalay Univ, Dept Geol, Mandalay, Myanmar

[4] Yangon Univ, Dept Geol, Yangon, Myanmar

[5] Dagon Univ, Dept Geol, Yangon, Myanmar

[6] MOGE, Yangon, Myanmar

来源：

GEOPHYSICAL RESEARCH LETTERS | 1999年 / 26卷 / 07期

关键词：

D O I：

10.1029/1999GL900136

中图分类号：

P [天文学、地球科学];

学科分类号：

07 ;

摘要：

The Mogok metamorphic belt, exposed along the NS trending Shan scarp and Sagaing fault, in the eastern part of Myanmar, has been regarded as Paleozoic to Precambrian for a long time. New observations in the Shan scarp area, close to the Sagaing fault, from Thaton in the south to Mandalay in the north, allowed us to collect samples of high grade metamorphic and intrusive rocks that have been analyzed by 40Ar/39Ar step heating method. The 13 samples we analyzed provide Oligocene to Lower Miocene ages for this metamorphism. Oriented thin sections and field observations suggest that this metamorphism was caused by a NNW-SSE to N-S ductile extension. Therefore, we suggest that this metamorphism is not directly related to the Sagaing fault, but could be instead related to the northward migration of the eastern Himalayan syntaxis, characterized by crustal thinning, resulting from the India-Asia oblique collision.

引用

页码：915 / 918

页数：4

共 17 条

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