Keywords:airborne gravity gradiometry, caldera structure
The airborne gravity gradiometry (e.g., JOGMEC, 2017) revealed that collapsed caldera shows a polygonal structure consisting of a combination of fractures in the direction along the caldera contour and radial fractures cutting through them. This structure is commonly found in the Quaternary calderas such as Kutcharo caldera, Teshikaga caldera, Sen-Yakeyama caldera, Sanzugawa caldera, Southern Kurikoma volcano caldera, Onikobe caldera, Hanayama caldera, Shiobara caldera, Shishimuta caldera, and Aso caldera.
Three-dimensional inversion of the airborne gravity gradiometry data enables to stereoscopically visualize the caldera structure.
Reference: JOGMEC, 2017, Report of survey on the potential of geothermal resources.