Digital mapping of surficial deposits in U-Thong area, Changwat Suphanburi

Abstract

Digital mapping of surficial deposits is applied geological mapping technique. The system is designed to provide a scientific analysis, by using remote sensing techniques and GIS techniques to help in the study that is focused on the unconsolidated sediments which is the basis information for the future development of the area. The study area covers an area of 556 square kilometers of Amphoe U-Thong, Amphoe Muang Suphanburi and Amphoe Bang Pla Ma. The prepared data are composed of satellite imagery (Landsat 8 OLI/TIRS, THEOS) and digital elevation model (DEM). The digital analysis, digital processing and interpretation are be used to classify the surficial deposits units in the study area. Besides, the observation data in the field are also collected in the study area to be used in the supervised classification and readjusted the boundary of the units to be the final surficial deposits map. The study was able to classify the surficial deposits unit in the flat plain area into eight units including Unit A: gravel and red silt, Unit B: red silt and red clay, Unit C: Dark brown silty clay, Unit D: Brownish grey silty clay Unit E: Brown silty clay, Unit F: Light brown clay, Unit G: Dark brown clay, and Unit H: Brown clay. Besides, the other two different units, namely; Unit bedrock and Unit urban-mine are also classified in the western part of mountainous area. Finally, main idea to classify surficial deposits units in U-Thong area that focuses in using satellite image and digital elevation model to classify the surficial deposits because the digital classification can be confirmed each unit identified from different spectral range. Anyway, the field data significantly to improve and confirm the detail and boundary of surficial deposits units by the second supervised classification. Although the digital classification cannot define the lithologic characteristic but they spend less time in the large area.