Abstract
Erosion rate at the Cat Ba island stations ranged from 0.196 to 0.282 mm/year shows that the average value in comparison with previous study results ranges from ±0.2 to ±0.5 mm with strong eroded level. Relative erosion rate value is the lowest at measuring stations X2 on April 8th, 2015 and the highest is at measuring stations Z7 on November 9th 2015, the average value in comparison with previous study results, ranges from ±0.05 to ±0.2 mm with average eroded level and from ±0.2 to ±0.5 mm with strong eroded level. The results of relative erosion rate on April 8th, 2015 are lower than on November 9th, 2015. Total rainfall values counted from the beginning of the study to the first measuring date (April 8th, 2015) and the second measuring date (November 9th, 2015) are 980.2 mm and 2280 mm, respectively. Therefore, the erosion rate of limestone is strongly affected by changes of total rainfall on the Cat Ba Island. Average relative erosion rates in this study are quite high at some submerged zone stations (about over 0.2 mm/year, on average) and quite low with some stations on land in comparison with some previous studies all over the world. Therefore, it needs more assessment in longer period to study more accurately some other impacts on weathering and erosion processes.
Highlights
The Cat Ba islands consisting of 367 islands are the third largest island group, behind The Phu Quoc and Cai Bau islands
We provide 2 years traversing microerosion meter (TMEM) results of limestone erosion at the Cat Ba Islands
TMEM instrument with high accuracy and precision, low standard deviation [4, 9] plays an important role in erosion studies
Summary
The Cat Ba islands consisting of 367 islands are the third largest island group, behind The Phu Quoc and Cai Bau islands. The Cat Ba Islands are the biggest limestone islands in tropical Southeast Asia, are the largest islands in Halong Bay Area with high potential for scientific study. Tropical karst landscapes have been strongly affected by intrusion and impact of global climate changes. Understanding the processes of weathering, erosion and the effects of climatic factors and natural conditions on limestone weathering process is very essential, as a basis for proposing efficient conservation measures of sustainable natural heritage of our world (Fig. 1) [1]. Cenozoic sedimentary formations (CZ) are distributed at the valley between the mountains and coastal areas (Fig. 1–3). Formation at CB1 exposure, near Cat Co 3 beach (N: 20o42’54,5”; E: 107o03’04,2”)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
