1973 Nemuro earthquake: Difference between revisions

| magnitude = 7.1 {{m|s|link=y}}<ref name="M 7.0" /> <br> 7.5-7.7 {{m|w|link=y}}<br>7.9{{m|t|link=y}}

| depth = {{convert|15|km|mi|abbr=on}}

| fault = [[Kuril–Kamchatka Trench]]

| type = [[Tsunami earthquake]]

| casualties =

}}

The '''1975 Kuril Islands earthquake''' which struck on June 10, nearly two years after the 1973 event was also considered an aftershock.<ref name="Yoshio">{{cite journal |last1=Yoshio |first1=Fukao |title=Tsunami earthquakes and subduction processes near deep-sea trenches |journal=Journal of Geophysical Research |date=10 May 1979 |volume=84 |issue=B5 |pages=2303–2314 |doi=10.1029/JB084iB05p02303 |bibcode=1979JGR....84.2303F |url=https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/JB084iB05p02303 |access-date=11 June 2021}}</ref> It ruptured the shallow interface of the Kuril Sunduction Zone with a focal depth of 15&nbsp;km, between the rupture zones of the 1973 and [[1969 Kuril Islands earthquake|1969 earthquakes]]. Although it had a smaller surface wave magnitude and JMA magnitude of 7.1,<ref name="Sapporo">{{cite journal |title=北海道東部沖地震のお知らせ |journal=Sapporo District Meteorological Observatory |date=1976 |trans-title=Report on the Earthquake Off E coast of Hokkaido |language=ja}}</ref><ref name="M 7.0">{{cite web |title=M 7.0 - Kuril Islands |url=https://earthquake.usgs.gov/earthquakes/eventpage/usp0000bdp/executive |website=earthquake.usgs.gov |publisher=USGS |access-date=11 June 2021}}</ref> it generated tsunami run-ups higher than the mainshock, at 5.5 meters.<ref name="Bryant">{{cite book |last1=Bryant |first1=Edward |title=Tsunami: The Underrated Hazard |date=2008 |publisher=Springer-Verlag Berlin Heidelberg |isbn=978-3-642-09361-6 |edition=2 |url=https://www.springer.com/gp/book/9783642093616|pages=129–138|chapter=5. Earthquake-generated tsunami|chapter-url=https://books.google.com/books?id=6lvl6i7r2CcC&pg=PA131}}</ref> Further analysis of event data has enabled the recalculation of the moment magnitude and tsunami magnitude of the earthquake. Two studies in 1978 and 1977 calculated the magnitude to be {{M|w}} 7.5–7.6 and 7.7 respectively.<ref name="Ioki">{{cite journal |last1=Ioki, K., Tanioka, Y. |title=Rupture Process of the 1969 and 1975 Kurile Earthquakes Estimated from Tsunami Waveform Analyses |journal=Pure and Applied Geophysics |date=2016 |volume=173 |issue=12 |pages=4179–4187 |doi=10.1007/s00024-016-1402-0 |bibcode=2016PApGe.173.4179I |doi-access=free }}</ref> Estimating the tsunami magnitude of the event using tsunami data assigned this event an {{M|t}} of 7.9. The 1975 aftershock is considered a [[tsunami earthquake]] due to the disproportionately large tsunami that it generated.<ref name="Ioki" />