ธรณีสัณฐานที่เกิดจากการกระท้าของธารน้ำในพื้นที่ลุ่มน้ำแม่ริม (Fluvial geomorphology in Mae Rim Basin)

Abstract

The purposes of this research were to investigate the spatial context of the Mae Rim River Basin, to study the types of geomorphology and classification caused by the fluvial process of the Mae Rim River and to create a geomorphology map of the study area. The study area was the Mae Rim River basin (covering 148.40 square kilometers) located in Saluang Sub district, Mae Rim District, and San Pa Yang Sub district, Mae Taeng District, Chiang Mai Province. Topography was analyzed by using 30-meter SRTM 1 Arc-Second Global high level numerical model data. Then the Topographic Position Index (TPI) was calculated by using SAGA GIS. The results showed that more than 60% of the studied areas are mountainous and hilly terrain. The area’s slopes are from west to east. The height is from 340 - 1440 meters above sea level. Most of the rock units are sedimentary and metamorphic and igneous. The sediments of the riverbeds and the stream sediments were found in the eastern plain. The main river is the Mae Rim River. In terms of geomorphology, there are 10 types of geomorphology, including areas of open slope( 34. 1 6%), plains(19.34 %), midslope ridges(9.18 %), midslope drainages(8.80 %), valleys(8.35 %), upper slopes(7.62 %), high ridges(5.82 %), streams (5.34 %), upland drainages(0.86 %), and local ridges(0.53%).