Examination of an investigation technique for activity on a fault-related fold in the Tenpoku region, northern Hokkaido, Japan

Nohara, Tsuyoshi   ; Kosaka, Hideki*; Kagohara, Kyoko*; Miwa, Atsushi*; Tokiwa, Tetsuya; Imaizumi, Toshifumi*

Activity in the fault-related fold zone in the Tenpoku region, where the influence of the interplate coupling is comparatively small, has been investigated to explain the contradiction between geomorphological and geodetic information. Moreover, the actual average shortening rate of the Sarobetsu fault zone was investigated using the balanced cross section analytical method that used 2D Move. The results of this study show that the estimation of the long term crustal shortening rate in a fault-related fold zone, based on information from the geological structure, is important. In this study, it has been confirmed that information on the deformation of the geological structure is consistent to information on the tectonic landform. A multiple lines of evidence approach, including geomorphological, geological and geodetic investigation methods, will reduce uncertainty related to the average shortening rate along the fault of the fault-related fold.