Abstract
In 2012 and 2017, temporary seismic networks were installed at a Kijiyama-Shitanotai geothermal field, Akita prefecture, Japan. Microseismic data was gathered using these networks for three months in each case. The networks were located in different areas of the geothermal system. The data was analyzed to identified of 499 local microearthquakes in 2017 and 475 in 2012 (a total of 974). From this data a velocity model was derived, and the earthquakes located. The shear waves recorded were analyzed for shear wave splitting (SWS). The SWS splitting results were used to derive a three-dimensional crack density model and polarization direction. The SWS result indicates a high in crack density and NE striking fractures in the north of the seismic network and NW striking in the south.
