Vertical movements of the Murono mud volcano in Japan caused by the Naganoken Kamishiro Fault Earthquake in 2014

We observed vertical movements of the Murono mud volcano, Niigata, Japan, caused by the Naganoken Kamishiro Fault Earthquake (M∈=∈6.7) on 22 November 2014. Precise levelling around the mud volcano was carried out on 27 November 2014, and the obtained elevation was compared with the data obtained for 11 November 2014. It was found that an elliptical uplift area, about 46 mm in magnitude and an order of magnitude smaller than that of the ones formed due to the past movements caused by the earthquakes in the same area, had been formed. It was considered that the structures of the shallow subsurface as well as the distance between the mud volcano and epicentre might play an important role in understanding the magnitude of vertical movements and distribution patterns