Crustal structure in the northern Fossa Magna region, central Japan, modeled from refraction/wide-angle reflection data

• Takeda Tetsuya

  Earthquake Research Institute, the University of Tokyo

• Sato Hiroshi

  Earthquake Research Institute, the University of Tokyo

• Iwasaki Takaya

  Earthquake Research Institute, the University of Tokyo

• Matsuta Nobuhisa

  Earthquake Research Institute, the University of Tokyo

• Sakai Shin'ichi

  Earthquake Research Institute, the University of Tokyo

• Iidaka Takashi

  Earthquake Research Institute, the University of Tokyo

• Kato Aitaro

  The Institute for Frontier Research on Earth Evolution, Japan Marine Science and Technology Center

Abstract

The northern Fossa Magna (NFM) is a back-arc rift basin filled with thick Tertiary sediments, which show strong NW-SE shortening deformation. In the NFM, there exist two major active fault systems, the Itoigawa-Shizuoka Tectonic Line active fault system (ISTL) and the Western Nagano Basin active fault system (WNB), both of which have great potentials to cause destructive earthquakes. By reanalyzing five sets of refraction/wideangle reflection data, we successfully obtained detailed and consistent models of the crustal structure in the NFM region. It was a very effective modeling procedure to incorporate vicinal seismic reflection data and geologic information. The geometries of the active faults in the NFM region were revealed. The ISTL is east dipping, and the WNB is northwest dipping. The Tertiary sedimentary layer (<4.0 km/sec) west and adjacent to the ISTL extends to a depth of 4-5 km. The basement rocks below the Central Uplift Belt (CUB) form a wedge structure, which suggests the westward movement of the CUB basement rocks.

Journal

• Earth, Planets and Space

  Earth, Planets and Space 56 (12), 1293-1299, 2004

  Society of Geomagnetism and Earth, Planetary and Space Sciences, The Seismological Society of Japan, The Volcanological Society of Japan , The Geodetic Society of Japan , The Japanese Society for Planetary Sciences

Keywords

• Crustal structure
• northern Fossa Magna
• refraction/wide-angle reflection data
• Itoigawa-Shizuoka Tectonic Line
• wedge structure

Details

• CRID: 1390001206514151168
• NII Article ID: 10017467270
• NII Article ID: 130003781003
• NII Book ID: AA11211921
• DOI: 10.1186/bf03353353
• ISSN: 18805981
• ISSN: 13438832
• NDL BIB ID: 7279595
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I7279595
• Web Site: https://link.springer.com/content/pdf/10.1186/BF03353353.pdf
• Web Site: https://link.springer.com/article/10.1186/BF03353353/fulltext.html
• Web Site: http://link.springer.com/content/pdf/10.1186/BF03353353
• Text Lang: en
• Data Source:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
• Abstract License Flag: Disallowed