Identification of gas migration pathways around faults and fold axes using high-precision methane measurement technology

Shimo, Michito*; Niwa, Masakazu   ; Miyakawa, Kazuya   ; Tonokura, Kenichi*; Tokunaga, Tomochika*

To develop a new approach to identify the fluid flow paths in the rock formation using high-precision gas concentration detection technology, we carried out the on-ground methane concentration measurement in the Horonobe area, northern Hokkaido. A set of NW-SE trending folds and faults occur through the area. Based on the findings of oil and gas seepage, the petroleum exploration survey was conducted in this area. These records suggest the existence of the fluid migration pathways around faults to reach the ground surface from an underground source. In this paper, we report the results of on-foot measurement of methane and carbon dioxide concentrations using CRDS apparatus and depict the possible migration paths around faults based on the distribution of gas seeps and geological and geophysical information reported in the existing literature.