SUMMARY
New results of the study on isotopic age of the Chu Va granitoid
massif of the Mường Hum Complex by U-Pb zircon isotopic dating method
Nguyễn Thị Xuân, Bùi Thế Anh,
Phạm Trung Hiếu, Nguyễn Thị Bích Thủy
The Chu Va granitoid massif of the Mường Hum Complex is situated in the west of the Phan Si Pan structural zone. It is composed of subalkaline granosyenite. Its composition and structure are similar to those of granitoid of the Yê Yên Sun Complex. Its mineralogical composition consists mainly of K-feldspath (microcline), acidic plagioclase (albite, oligoclase), and quartz. Chromatic minerals include only hornblende and biotite. Structure of the rock is irregular-grained with a gneiss-oriented texture.
New
results of the study on the isotopic age of the Chu Va granitoid massif by U-Pb
zircon isotope dating method on zircon collected from the Chu Va granitoid
massif have been indicating that its age is 123.7±1.9 Ma, corresponding to the
age of the Yê Yên Sun Complex. The new age values are quite different in comparing
with previously determined age values, which vary in a range of 220-250 Ma.
Granitoid of the Chu Va massif was formed during a period of intrusive igneous
activity in Việt
Người biên tập: Bùi Minh Tâm