1:45 PM - 3:15 PM
[O06-P25] Estimation of the crater of a submarine volcano in Shichigahama from near Katsurashima Island, Shiogama City
Keywords:volcano, underwater volcanic, intrusive rock
The dacitic volcanic breccia Otb is distributed in the Otsuka Formation from Uradogatsurajima to Funairishima in Shichigahama Town and Shiogama City. Although previous studies have described it as an 'underwater pyroclastic sediment,' this study assumes it as an 'intrusive rock' based on lithological descriptions, and aims to estimate the rough location of the old crater by tracing its distribution from Katsura Island to Funairi Island. At present, we attempt to infer that Otb, a dacitic volcanic breccia in the Otsuka Formation, is an intrusive rock. After verifying that it is an intrusive rock, we would like to discuss where the underwater volcanic crater that once existed in the area and resulted in the dacitic breccia Otb existed.