Abstract
Gravel beach shows more dynamic profile change than sand beach, and is vulnerable to erosion. An artificial reef may be a structure to reduce beach erosion. However, there are many cases still suffering from beach erosion after installation of artificial reefs, indicating that more studies about beach processes are required. This study aims to investigate shoreline change at Shichirimihama Beach by using WEB camera system and beach profile changes based on field observation. Results showed that high energy wave during typhoon is the main reason leading to the continuous shoreline retreat. High wave approaching from E-SSE direction leaded to the formation of berm on the top of beach face at the location without artificial reef. In the area behind artificial reef, berm formation was not observed and shoreline almost stood by at its orginal position. However, when highwave approached to the coast from S-SW direction, sediment on beach face was washed out and the shoreline reatreated on the entire study area. This results indicated that in Shichirimihama beach wave direction also plays an important role on beach morphology change
