Japan Geoscience Union Meeting 2025

Presentation information

[J] Oral

H (Human Geosciences ) » H-TT Technology & Techniques

[H-TT17] Geographic Information System and Cartography

Thu. May 29, 2025 1:45 PM - 3:15 PM 104 (International Conference Hall, Makuhari Messe)

convener:Mamoru Koarai(Earth Science course, College of Science, Ibaraki University), Kazunari Tanaka(Department of Civil Engineering and Urban Design, Faculty of Engineering, Osaka Institute of Technology), Kazuhiko W. Nakamura(The University of Tokyo), Tomohiko Arahori(Department of Geography, Nihon University College of Humanities and Sciences), Chairperson:Mamoru Koarai(Earth Science course, College of Science, Ibaraki University), Tomohiko Arahori(Department of Geography, Nihon University College of Humanities and Sciences), Kazunari Tanaka(Department of Civil Engineering and Urban Design, Faculty of Engineering, Osaka Institute of Technology)

1:45 PM - 2:00 PM

[HTT17-01] Estimation of Paleotopography in the Okayama Airport Area Using Machine Learning Methods

★Invited Papers

*Junji Yamakawa1 (1.Graduate School of Environmental, Life, Natural Science and Technology, Okayama University)

Keywords:Digital Elevation Model, Paleotopography, Machine Learning, Modeling

Okayama Airport (OKJ) is a regional airport located in Kita Ward, Okayama City, Okayama Prefecture, approximately 15 km northwest of the city center. The area currently occupied by the airport once featured undulating terrain composed of the middle layer of the Tomiyoshi Formation within the Kibi Group. This formation is characterized by alternating layers of sandy deposits from meandering river channels and muddy floodplain deposits. However, this original terrain was lost due to the construction of the airport. This study aimed to estimate and examine the pre-construction topography of the Okayama Airport area using machine learning applied to a Digital Elevation Model (DEM).

The DEM used in this study was derived from LiDAR-based topographic data provided by the Geospatial Information Authority of Japan (GSI), specifically the Fundamental Geospatial Information DEM05A (5-meter mesh). The machine learning processes were conducted using Google Colaboratory, a Python IDE (Google, 2025). Pre-construction aerial photographs were obtained from GSI tiles (GSI, 2025), and geospatial analyses were performed using QGIS (QGIS Development Team, 2025). The Contour plugin in QGIS was used to generate contour lines.

Two machine learning algorithms were developed to estimate the paleotopography of the Okayama Airport area. The results of both algorithms indicated the presence of continuous topographical features extending from outside the airport area into its boundaries. Additionally, three depressions were identified within the airport area. However, the southwestern depression was inconsistent with the features observed in pre-construction aerial photographs, suggesting the need for further refinement of the machine learning algorithms for topographical estimation.