| Title: | Cause of destructive strong ground motion within 1–2 s in Mukawa town during the 2018 Mw 6.6 Hokkaido eastern Iburi earthquake |
| Authors: | Takai, Nobuo Browse this author →KAKEN DB |
| Shigefuji, Michiko Browse this author |
| Horita, Jun Browse this author |
| Nomoto, Shingo Browse this author |
| Maeda, Takahiro Browse this author |
| Ichiyanagi, Masayoshi Browse this author |
| Takahashi, Hiroaki Browse this author |
| Yamanaka, Hiroaki Browse this author |
| Chimoto, Kosuke Browse this author |
| Tsuno, Seiji Browse this author |
| Korenaga, Masahiro Browse this author |
| Yamada, Nobuyuki Browse this author |
| Keywords: | The 2018 Hokkaido eastern Iburi earthquake |
| Strong ground motion |
| Velocity structure |
| Temporary strong motion observation |
| Microtremor measurement |
| Multichannel analysis of surface wave |
| S-wave velocity |
| Site amplification |
| Issue Date: | 2019 |
| Journal Title: | Earth, Planets and Space |
| Volume: | 71 |
| Issue: | 1 |
| Start Page: | 67 |
| Publisher DOI: | 10.1186/s40623-019-1044-4 |
| Abstract: | We investigated the cause of destructive ground motion during the 2018 Hokkaido eastern Iburi earthquake. We conducted strong motion observations of aftershocks and microtremors and the surface wave method in the damaged areas of the town of Mukawa, Hokkaido prefecture, Japan. The ground accelerations were continuously recorded during a period of approximately 3 months after the main shock on September 6, 2018. The heavily damaged buildings were mainly situated around the strong motion station (HKD126) in Mukawa town. Such concentration of damage can be explained by the strong power that was observed in the 1–2 s period of the response spectrum at this station. We estimated the S-wave velocity profiles of this station site and a temporary station site that was installed on a nearby hill. The estimated S-wave velocity, which was inverted from phase velocity structures with the microtremor array and the surface wave method observations explained the difference in the SH-wave amplification characteristics between the two sites. An analysis of HKD126 and the temporarily observed records clearly indicates the strong effects of the local geological conditions on the heavily damaged area of Mukawa. The strong ground motion power generated during the main shock in Mukawa for 1–2 s period was mainly amplified by this shallow underground velocity structure. |
| Rights: | https://creativecommons.org/licenses/by/4.0/ |
| Type: | article |
| URI: | http://hdl.handle.net/2115/74684 |
| Appears in Collections: | 工学院・工学研究院 (Graduate School of Engineering / Faculty of Engineering) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)
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