title: Geophysics. Migrating tremor off southern Kyushu as evidence for slow slip of a shallow subduction interface.
abstract: Detection of shallow slow earthquakes offers insight into the near-trench part of the subduction interface, an important region in the development of great earthquake ruptures and tsunami generation. Ocean-bottom monitoring of offshore seismicity off southern Kyushu, Japan, recorded a complete episode of low-frequency tremor, lasting for 1 month, that was associated with very-low-frequency earthquake (VLFE) activity in the shallow plate interface. The shallow tremor episode exhibited two migration modes reminiscent of deep tremor down-dip of the seismogenic zone in some other subduction zones: a large-scale slower propagation mode and a rapid reversal mode. These similarities in migration properties and the association with VLFEs strongly suggest that both the shallow and deep tremor and VLFE may be triggered by the migration of episodic slow slip events.
authors.affiliation: Institute of Seismology and Volcanology (SEVO), Faculty of Sciences, Kyushu University, 2-5643-29 Shin'yama, Shimabara 855-0843, Japan. yamac@eri.u-tokyo.ac.jp.
authors.forename: Y
authors.initials: Y
authors.lastname: Yamashita
authors.affiliation: Nansei-Toko Observatory for Earthquakes and Volcanoes, Graduate School of Science and Engineering, Kagoshima University, 10861 Yoshino-cho, Kagoshima 892-0871, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Yakiwara
authors.affiliation: National Research Institute for Earth Science and Disaster Prevention, 3-1 Tennodai, Tsukuba 305-0006, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Asano
authors.affiliation: Institute of Seismology and Volcanology (SEVO), Faculty of Sciences, Kyushu University, 2-5643-29 Shin'yama, Shimabara 855-0843, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Shimizu
authors.affiliation: Institute of Seismology and Volcanology (SEVO), Faculty of Sciences, Kyushu University, 2-5643-29 Shin'yama, Shimabara 855-0843, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Uchida
authors.affiliation: Nansei-Toko Observatory for Earthquakes and Volcanoes, Graduate School of Science and Engineering, Kagoshima University, 10861 Yoshino-cho, Kagoshima 892-0871, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Hirano
authors.affiliation: Graduate School of Fisheries Science and Environmental Studies, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Umakoshi
authors.affiliation: Nansei-Toko Observatory for Earthquakes and Volcanoes, Graduate School of Science and Engineering, Kagoshima University, 10861 Yoshino-cho, Kagoshima 892-0871, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Miyamachi
authors.affiliation: Institute of Seismology and Volcanology (SEVO), Faculty of Sciences, Kyushu University, 2-5643-29 Shin'yama, Shimabara 855-0843, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Nakamoto
authors.affiliation: Institute of Seismology and Volcanology (SEVO), Faculty of Sciences, Kyushu University, 2-5643-29 Shin'yama, Shimabara 855-0843, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Fukui
authors.affiliation: Institute of Seismology and Volcanology (SEVO), Faculty of Sciences, Kyushu University, 2-5643-29 Shin'yama, Shimabara 855-0843, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Kamizono
authors.affiliation: Faculty of Fisheries, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Kanehara
authors.affiliation: Earthquake Research Institute (ERI), The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Yamada
authors.affiliation: Earthquake Research Institute (ERI), The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Shinohara
authors.affiliation: Earthquake Research Institute (ERI), The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Obara