Japan Geoscience Union Meeting 2015

Presentation information


Symbol H (Human Geosciences) » H-GM Geomorphology

[H-GM22] Geomorphology

Tue. May 26, 2015 3:15 PM - 4:00 PM 101B (1F)

Convener:*Hiroshi Shimazu(Department of Geography, Faculty of Geo-Environmental Science, Rissho University), Chiaki T. Oguchi(Institute for Environmental Science and Technology, Graduate School of Science and Engineering, Saitama University), Masayuki Seto(Fukushima Future Center for Regional Revitalization, Fukushima University), Chair:Sachi Wakasa(Faculty of International Resource Sciences, Akita University)

3:15 PM - 3:30 PM

[HGM22-01] Terrain classification of Southwest Japan including the Seto Inland Sea by object based area segmentation

*Junko IWAHASHI1, Yuki MATSUSHI2, Hiroshi FUKUOKA3 (1.GSI of Japan, 2.Kyoto University, 3.Niigata University)

Keywords:Fundamental Geospatial Data, seafloor topography, object based area segmentation, DEM, terrain classification, Seto Inland Sea

Terrain classification studies have been predominantly pixel-based using DEMs. Previously the corresponding author developed a pixel-based automated classification method of topography using slope gradient, convexity, and texture calculated from a DEM for small-scaled classification of plains, terraces, hills, mountains, and volcanos (Iwahashi, 1994; Iwahashi and Pike, 2007). However, a pixel-based approach could not handle scale issues or increasing noise associated with enlarging resolution of DEMs. In addition, pixel data include problems of data volume and difficulties in spatial joining with attributes of thematic maps.
Recently object based techniques for land-cover classification using color orthoimages or satellite images have become popular. In this presentation, the authors introduce the method of making terrain-type polygons by object-based software using a combined image of geometric signatures. We produced a terrain classification map of Southwest Japan including the Seto Inland Sea using a 150-m DEM which was a mosaic of land elevation and seafloor elevation. The terrain-type polygons were statistically compared with other thematic maps such as landslide distribution and lithology.
This study was carried out within a framework of "Mapping of large landslides based on the sea-land combined terrain classification: case study of the overall Outer Zone of Southwest Japan including the Nankai Trough" which was a theme in '2014 Collaborative Research with the Disaster Prevention Research Institute, Kyoto University'. We would also like to thank the Japan Coast Guard who provided the 150-m and 450-m Geographical Feature Meshes Data of Southwest Japan.

Iwahashi, J. (1994):Development of landform classification using digital elevation model. Disaster Prevention Research Institute annuals (Kyoto Univ.), 37(B-1), 141-156. (in Japanese with English abstract and figures)
Iwahashi, J. and Pike, R. J. (2007):Automated classifications of topography from DEMs by an unsupervised nested-means algorithm and a three-part geometric signature.Geomorphology,86,409-440.