A minor earthquake occurred on July 26, 1972 near Bengough, Saskatchewan, at 49°21′ N ± 5′, 104°56′ W ± 4′ with origin time 03h58m19s ± 1s GMT. The magnitude was mb 3.7 ± 0.2 and the focal depth less than 10 km. The radius of perceptibility was 30 km and the maximum intensity was IV on the Modified Mercalli scale. There was no reported damage. The large ratio of Love- to Rayleigh-wave amplitudes indicated that the event was not due to the alleged sudden collapse of a solution cavity in the salt formations. The Love- and Rayleigh-wave radiation patterns are consistent with a vertical strike-slip fault striking approximately N 30 °E. Three other earthquakes are known to have occurred in the general area of the Williston Basin—the largest in 1909 was probably about mbgraphic.

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