Joint Inversion of Multiphysics data in Yamagawa Geothermal Area

Endo, M, A. Gribenko, D. Sunwall, M. S. Zhdanov, T. Miura, H. Mochinaga, N. Aoki, and T. Mouri, 2018, Integrated interpretation of multimodal geophysical data for exploration of geothermal resources – Case study: Yamagawa geothermal field in Japan: SEG Technical Program Expanded Abstracts, 1949-4645

Japan Oil, Gas and Metals National Corporation (JOGMEC) has been developing the proper geophysical interpretation technology for exploration and appraisal of geothermal resources in Japan, and has conducted a wide variety of geophysical surveys in Yamagawa geothermal field, Japan

Geophysical data acquired in Yamagawa geothermal field:

  •  Magnetotelluric data
  • Gravity data
  • Magnetic data
  • Seismic data

Magnetotelluric (MT) data:

New Energy and Industrial Technology Development Organization
(NEDO) acquired

  • Total 134 stations (red)
  • Impedance tensors processed using remote reference station data
    40 frequencies from 0.00055 to 374 Hz

Ibusuki City acquired in 2015

  • Total 25 stations (blue)
  • 40 frequencies from 0.00034 to 320 Hz

Gravity and Magnetic Data:

Seismic Data

3D seismic reflection and refraction data acquired by JOGMEC in 2013

3D seismic velocity model

Seismic surfaces

  • Top of Nansatsu formation
  • Top of Dacite
  • Near-surface high velocity volume

Seismic surfaces

Seismic velocity modal

Vertical sections of 3D resistivity and density models produced by the joint inversion

Recovered resistivity overlaid with recovered magnetization vector

Recovered density overlaid with recovered magnetization vector