The surface environmental changes were reconstructed in the lower reaches of the Kizu River, Kyoto, Japan using numerous borehole data. Four fluvial channels formed by lacustrine delta progradation at ca. 0–10m depth in the lower reaches of the Kizu River were clarified based on a subsurface geological analysis. These channels flowed toward the paleo-Ogura Lake and diverged to the north with the gradient decreased. The lacustrine delta systems were formed from the post–glacial period to the end of the 16th century. The new bedload–dominated rivers with crevasse splay system developed by the reduction in the lake area of the Ogura Lake due to artificial changes such as bank construction and shifting of river channels since the end of 16th century.
ISSN: 1792-9040 (Print)