Figure8-5 Extension and compression in the Chugoku-Shikoku region.

The direction of the two straight lines that cross each other in the figure are those of the maximum extension (or minimum compression; red) and the maximum compression (or minimum extension; blue). Also, the lengths of the straight lines are in proportion to the amount of the extension or compression.

[Compiled from data from Geographical Survey Institute and 'Active Faults in Japan (Revised Edition)']

A: The past approximately 100 years.


Compression is seen in a roughly east-west direction in the eastern and central part of the Chugoku region. Significant compression is seen in a northwest-southeast direction in the southwestern part of the Shikoku region. The large values in the west of Tottori City are due to the 1943 Tottori Earthquake.

B: The past approximately 10 years.


Compression is seen in a northwest-southeast direction in the Shikoku region.