Establishment of digital 3D map based on discrete elevation point data measured in the field

Abstract

This study established a survey zone digital elevation model (DEM) using highly precise and regularly updated three-dimensional coordinates of the surface of barchan dunes using CASS9.0 software. Two contour plots were drawn, one for the entire survey zone drawn with a contour interval of 0.005 m and one for an individual sand dune drawn with a contour interval of 0.001 m. ArcMap10 was used to define the projection of the created contour lines in DWG format and export the data into shape files to enable the creation of a triangulated irregular network (TIN). Next, TIN data was converted into raster data to facilitate our analysis and data processing. We created the final TIN by using an additional smoothing processing on the desired area that had been clipped out. We added the TIN data to the ArcScene module to establish the final 3D numerical model of barchan dunes. This model extracts and analyzes the changes in the characteristic parameters of the barchan dune as its topography changes in real time so researchers can visualize dune migration and evolution. Their understanding is enhanced by comparing and superposing the various 3D dune models on different days.