Uploaded on October 11, 2021

Event Event time: 2021-10-07 22:41:23.0 (JST, JMA), 2021-10-07 13:41:24.5 (UTC, USGS) Location: 35.590°N, 140.103°E (JMA), 35.577°N, 140.070°E (USGS) Depth: 75km (JMA), 62km (USGS) Magnitude: Mj5.9 (JMA), Mww5.9 (USGS)

Information in our site

• Strong Ground Motions (NIED K-NET, KiK-net data, MeSO-net) [in English]
• 観測された強震動データ (防災科研K-NET, KiK-net, MeSO-net) [in Japanese]
• Prompt report on 2021/10/07 22:41 NW Chiba Pref. Earthquake [in English]
• 強震観測速報 (2021年10月7日22時41分千葉県北西部の地震) [in Japanese]

Direct links

• M 5.9 - 4 km WSW of Chiba, Japan, by USGS Earthquake Hazards Program

Related institutions

• United States Geological Survey (USGS), USA
• Seismic Monitor, Incorporated Research Institutions for Seismology (IRIS)

The Generic Mapping Tools (GMT, Wessel and Smith, Eos, 79, 579, 1998) was used to make the figure of the epicenter, which is from JMA (https://www.data.jma.go.jp/svd/eqev/data/daily_map/20211007.html). The land topography and ocean bathymetry are from GEBCO Compilation Group (2020, GEBCO 2020 Grid, doi:10.5285/a29c5465-b138-234d-e053-6c86abc040b9).

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