USGS - science for a changing world

Pacific Coastal & Marine Science Center

Tsunamis & Earthquakes

USGS PCMSC Tsunami and Earthquake Studies

 

1952 Tokachi-Oki Earthquake & Tsunami

The recent September 25, 2003 M 8.3 earthquake near Hokkaido, Japan is located in the same region as the M 8.1 1952 Tokachi-Oki earthquake. During his stay at the USGS as a visiting scientist, Dr. Kenji Hirata (JAMSTEC) led a study examing the slip distribution of the 1952 earthquake using tsunami records. Below are excerpts from the presentation from the 2003 Annual Meeting of the Seismological Society of America on the 1952 Tokachi-Oki earthquake and tsunami. See spatial relationship between the 1952 and 2003 earthquakes.

References:

Hirata, K., Geist, E.L., Satake, K., Tanioka, Y., and Yamaki, S., 2003, Slip distribution of the 1952 Tokachi-Oki earthquake (M 8.1) along the Kuril Trench deduced from tsunami waveform inversion: Journal of Geophysical Research, v. 108, no. B4, p. ESE 6-1 - ESE 6-15.

Geist, E.L., Hirata, K., Satake, K., Tanioka, Y., and Yamaki, S., 2003, Reconciling source areas determine from aftershock and tsunami data: The M 8.1 1952 Tokachi-Oki earthquake along the Kuril subduction zone: Seismological Research Letters, v. 74, p. 221.

see also:
Nanayama, F., Satake, K., Furukawa, R., Shimokawa, K., Atwater, B., Shigeno, K., and Yamaki, S., 2003, Unusually large earthquakes inferred from tsunami deposits along the Kuril trench: Nature, v. 424, p. 660-663.

purpose

damage and casualties

Photo from the 1952 tsunami. Floating ice was brought onshore during tsunami inundation and damaged structures.

tsunami ice breaking house

Photo of 1952 tsunami during inundation.

tsunami inundation

Photo of damage following 1952 tsunami.

tsunami damage

Coastline highlighted in orange had observed runup less than 4 m. Red coastline had observed runup greater than 4 m. Star is 1952 epicenter. Circles are aftershocks from 1952 earthquake.

runup distribution

Data from tide gauge stations shown below are used to analyze the 1952 earthquake.

tide gauge stations

In some cases, ice blocked the tide gauge station and corrupted the record.

ice blocking tide station

Geometry of 1952 rupture. Slip on subfaults A thru J is determined. Depth contours of subducting Pacific Plate indicated at 50, 75, and 100 km. Next slides show profile Q-P.

rupture geometry

depth profile

inversion scheme

green's function

Results of inversion. Highest slip is on shallow subfaults F and I near trench and subfault E.

slip distribution

Comparison of predicted and observed records.

predicted and observer records

Comparison of predicted and observed tsunami runup along Hokkaido coastline.

predicted and observed runup

Stress drop distribution derived from slip inversion. Highest stress drop correlates with highest observed seismic intensity.

stress drop distribution

Generally, aftershocks are located in lower stress-drop regions.

aftershock related to stress drop

Location of historic earthquake relative to the 1952 Tokachi-Oki rupture. Note that the recent 9/25/03 epicenter is very close to the 1952 epicenter.

location of historic earthquakes

Topography of subducting Pacific plate may influence rupture mechanics.

topography of subducting plate

The University of Tokyo Earthquake Research Institute has computed the slip distribution for the 2003 earthquake :

ERI Slip Distribution
Photo courtesy of University of Tokyo Earthquake Research Institute

(click on image above to go to the ERI page)

Note that the epicenters for the 1952 and 2003 earthquakes are very close to each other. The highest slip for the 2003 earthquake occurs near the 1952 subfaults B and D with low slip (see above), but also near the high slip subfault E. Subfault E may outline an asperity along this fault. Initial tsunami modeling by Tohoku University indicates that highest tsunami amplitudes were in the Cape Erimo region (southern tip of coastline shown above) in contrast to the Kushiro-Kiratappu region for the 1952 tsunami.

 

Accessibility FOIA Privacy Policies and Notices

USA.gov logo U.S. Department of the Interior | U.S. Geological Survey
URL: http://walrus.wr.usgs.gov/tsunami/SSA03.html
Page Contact Information: Laura Zink Torresan
Page Last Modified: 22 October 2008 (lzt)