SUMMARY

Classification of North Việt Nam granitoids on the tectonic basis

Hoàng Sao, Dương Đức Kiêm

The complexes of granitoid are closely related to tectonic setting, therefore one can successfully use the mineralogy and chemistry of granitoids to charaterize the tectonic regime of different regions in the earth.

In this paper, we use the data on mineralogy and chemistry of granitoid complexes  of Izokh [2] and Lacroix [3], and demonstrate them on different tectonic environment diagrams [5]. The final results are as follows:

Granitoids of the complexes Sông Chảy, Điện Biên, Phia Bioc, Pia Oăc, Đèo Mây, Yê Yên Sun, Mường Hum and Bản Chiềng are orogenic granitoids, among them granitoids of Điện Biên and Đèo Mây complexes are continental arc granitoids (CAG), granitoids of Sông Chảy, Phia Bioc, Pia Oăc, Yê Yên Sun complexes are continental collision granitoids (CCG), granitoids of Mường Hum and Bản Chiềng complexes are post-orogenic granitoids (POG).

Granitoids of Ca Vịnh, Phu Sa Phìn, Nậm Xe - Tam Đường complexes are considered as anorogenic, among them granitoids of Ca Vịnh complex are oceanic plagiogranite (OP), granitoids of Phu Sa Phìn and Nậm Xe - Tam Đường complexes are rift-related granitoids (RRG).

Ngày nhận bài: 27-9-2003

Người biên tập: Trần Văn Trị