1987 Chiba earthquake
| 千葉県東方沖地震 | |
Strike-slip | |
| Max. intensity | JMA 5−[4] MMI VII (Very strong) |
|---|---|
| Casualties | 2 dead, 144 injured |
The 1987 Chiba Prefecture offshore earthquake (
Boso Peninsula in Chiba Prefecture at 11:08:01 JST
on December 17, 1987.
Tectonic setting
The crustal structure in the southern
Okhotsk Plate along the line of the Sagami Trough and beneath the Eurasian Plate along the line of the Nankai Trough. Further to the east, the Pacific Plate is subducting beneath the Okhotsk and Philippine Sea plates along the line of the Japan Trench.[3] A velocity analysis of the region beneath Kanto suggests that the wedge of oceanic mantle lithosphere of the Philippine Sea Plate in contact with the Pacific Plate is affected by serpentinization as shown by the anomalously low seismic velocity. The boundary between the serpentinized and unmetamorphosed parts of the mantle wedge is interpreted to be vertical and NNW–SSE trending.[5]
Earthquake
The earthquake had a
reverse faulting.[3] The earthquake is interpreted to have ruptured part of the boundary between the two parts of the Philippine Sea Plate mantle wedge.[5]
Damage
According to the materials of the Fire and Disaster Prevention Division of the Chiba Prefecture General Affairs Department, two deaths (one in
Mobara and another in Ichihara), 26 serious injuries and 118 minor injuries were reported. 16 buildings collapsed, 102 were severely damaged, and 63,692 suffered minor damage. Three fires, power outages, and train service disruptions were also reported.[6][7] Liquefaction was observed on landfills and riverbanks. Even though most of the damage occurred in Chiba Prefecture, damage and landslides were also reported in Kanagawa Prefecture.[8][9][10]
See also
- List of earthquakes in 1987
- List of earthquakes in Japan
- 2012 Chiba earthquake
- 2021 Chiba earthquake
References
- ^ "M 6.7 - 10 km SW of Mobara, Japan - Technical Summary". earthquake.usgs.gov.
- ^ "M 6.7 - 10 km SW of Mobara, Japan". earthquake.usgs.gov.
- ^ .
- ^ "震度データベース検索". 気象庁. Retrieved 2022-04-11.
- ^ .
- ^ "1987年千葉県東方沖地における災害情報の伝達と市町村・住民の対応] 東京大学社会情報研究所廣井研究室" [1987 Transmission of disaster information off the east coast of Chiba Prefecture and response of municipalities and residents] (PDF). Hiroi Laboratory, Institute of Social Information, University of Tokyo. Archived from the original (PDF) on 2016-03-05. Retrieved 2022-04-11.
- ^ Butts, David (December 17, 1987). "Earthquake in Japan kills two, injures 53". United Press International. Retrieved April 12, 2022.
- ^ "千葉県東方沖地震" [Chiba Prefecture East Offshore Earthquake]. typhoon.yahoo.co.jp (in Japanese). Retrieved April 12, 2022.