Determination of the junction angle in fluvial channels from georeferenced aerial images from Google Earth Pro and UAV

Determinação do ângulo de junção em canais fluviais a partir de imagens aéreas georreferenciadas obtidas do Google Earth Pro e com VANT

Abstract

The junction angles in fluvial channels are determined from complex erosion and deposition processes, resulting from river-flow dynamics, bed and margin morphology, and so on. Knowledge regarding these angles is important in order to better understand the existing conditions in a basin. In this sense, the objective of the present study was to determine the junction angles on fluvial channels, called α, β and γ, applying the law of cosines. Georeferenced Google Earth Pro images and UAV images were used. Then, the values calculated from the georeferenced aerial images were compared with the values calculated from the minimum energy principle. To visualize and understand the obtained angles, the Junction Angles Diagram was used. The obtained result shows that the methodology using georeferenced aerial images have good performance for determining junction angles on fluvial channels.

Keywords:
georeferencing; junction angle; law of cosines.