SUMMARY

Sông Cả fault zone with its extension in Lào territory

Bùi Văn Thơm, Nguyễn Trọng Yêm, Nguyễn Văn Hùng

The extension of Sông Cả fault zone to the NW into Laos is called Mường Khâm fault zone. It consists of a principal fault zone, a secondary fault zone and a branch fault zone. It strikes NW-SE and dips NW. In the Neotectonic period, it has undergone two tectonic phases: the Early Phase : ((Late Miocene - Early Pliocene) when the fault zone was in left lateral strike slip movement, and the Late Phase (Late Pliocene - Quaternary) when the fault zone was in right lateral strike slip movement. The right lateral displacement in the Late Pliocene - Quaternary period reached 3,500m with an average slipping rate of about 10.2 mm/year and the vertical displacement reached about 200 m. At present this fault zone is still active. The results of this study have contributed to the clarification of the Sông Cả fault zone's activities in the Neotectonic period.

Người biên tập: GS.TS Trần Văn Trị