Tidal channel distribution in relation to surface sedimentary facies based on remotely sensed data

摘要

Tidal channel networks are important factors influ-encing the morphodynamics of tidal flats and surface sedimentary facies. Here we investigate the relationship between channel dis-tribution and sedimentary facies in Geunso Bay tidal flat, Korea. The tidal channel networks were extracted from a high spatial res-olution aerial photograph, and for each sedimentary facies the pat-tern of tidal channel distribution was compared in terms of fractal analysis, channel density, and distance from the channel. The tidal channels in each sediment facies had relatively constant meander-ing patterns, but the density and complexity were distinguishable. The second fractal dimension was 1.87 in the mud flat, 1.41 in the mixed flat, and about 1.30 in the sand flat. The channel density was 0.036-0.06 m/m~2 in the mud flat and 0-0.024 m/m~2 in the mixed and sand flat areas. This implies that the tidal channels in the mud flat area represent a complex and dendritic pattern with high density compared to those in the mixed or sand flat areas. The results were used to test the applicability of adjusting sedimentary facies clas-sification generated from interpolation of survey data. We quan-titatively estimated the pattern of tidal channel distribution for each sedimentary facies based on a high spatial resolution aerial photograph. We suggest that tidal channel network features can be useful to surface sedimentary facies classification in tidal flats.