SUMMARY
Analysis of
geomorphologic features on the geological formations in Đà river
downstream valley
Nguyễn Xuân Nam, Trần Tân Văn, Hạ
Văn Hải
Đà River is a large
river originating from Yunnan province in China and flowing through Northwest Việt Nam with a
length of 527 km. It flows mainly in northwest- southeast direction but in its
downstream section from Hòa Bình it changes the direction to the north and merges with the Red river at Việt
Trì. This paper presents the results of
research in the Đà River valley from Hòa
Bình to Việt
Trì with the semi-automated geomorphologic
mapping, analysis of some types of landform and their interaction with the
geological formations. The results obtained show that the topographic surface
is highly dependent on the geological formations and based on this various
landforms such as denudational, erosional, tectonic, etc. have been more
accurately identified. The paper also gives an interpretation on the age of the
Đà river
valley, which shows that the downstream valley of the Đà river just
appeared in the Middle Pleistocene.
Người
biên tập: GS.TSKHĐặng Văn Bát.