ASSESSING THE MOTIVE OF EROSION PROCESS OF RIVERS IN THE MID-CENTRAL PART OF VIETNAM
AbstractAbstract: In this report, we wish to show some initial achievements of our researches about the motive of erosion process of rivers in the mid-central part of Vietnam from Quang Binh to Phu Yen (They include Gianh river, Nhat Le river, Thach Han river, Huong river, Thu Bon river, Tra Khuc river, Ba river). In order to assess danger's degree generated from the rivers themself, we apply two criteria including the intensity and the rate of erosion. Among which, erosion intensity is defined by erosion coefficient (Ke - %) and erosion width (Be - m) at measuring time. With the coefficient is the ration between total erosion lenght at measuring time and the length of the studied segment. The annual pace of erosion Ve (m/year) is measured by the width of erosion each year or each flood. From this motive scale and results of surveys and monitorings in the field, it is possible to assess and propose the basic comments associated with the eroion motive of rivers in the mid-central part of Vietnam. This is expected will be very useful for following studyings of geological hazards.
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