Fault Exposure at Ikeda, Munakata City, Fukuoka Prefecture

DOI Web Site 1 References
  • NAKAMURA Yosuke
    Fukushima University, Fukushima Future Center for Regional Revitalization
  • MIZUNO Kiyohide
    Institute of Geology and Geoinformation, Geological Survey of Japan, AIST

Bibliographic Information

Other Title
  • 福岡県宗像市池田において発見された活断層露頭
  • フクオカケン ムナカタシ イケダ ニ オイテ ハッケン サレタ カツダンソウ ロトウ

Search this article

Abstract

 A new outcrop of a reverse active fault was observed at Ikeda, Munakata City, Fukuoka Prefecture. Late Quaternary fluvial terraces in this area are divided into five levels: Ikeda I terrace to Ikeda V terrace in descending order. Ikeda III Terrace, near the outcrop, is covered with a loamy soil and aqueous silt. Kikai-Tozurahara tephra (95ka) is contained at the middle of the silt. We estimate that the Ikeda III terrace was formed at approximately 100ka. The strike and dip of the fault plane are N20°W and 28°W, respectively. Terrace gravels (Ikeda III terrace gravel), Ikeda Formation (Paleogene) and Kitazaki Granodiorite (Cretaceous) in this outcrop were deformed. The displacement of terrace gravels on this thrust is about 3.2m in the vertical component. From the approximate age of the terrace and the vertical displacement of active faults, the average long-term vertical slip rates is estimated to be 0.03mm/yr. This outcrop overlaps with geologic boundary fault and there is reactivity along the scar of the geologic boundary fault between the Paleogene and Mesozoic basement rocks.

Journal

References(1)*help

See more

Keywords

Details 詳細情報について

Report a problem

Back to top