Editing Earthquake prediction (section)

==== Seismic gaps ====
At the contact where two tectonic plates slip past each other every section must eventually slip, as (in the long-term) none get left behind. But they do not all slip at the same time; different sections will be at different stages in the cycle of strain (deformation) accumulation and sudden rebound. In the seismic gap model the "next big quake" should be expected not in the segments where recent seismicity has relieved the strain, but in the intervening gaps where the unrelieved strain is the greatest.<ref>{{Harvnb|Scholz|2002|loc=§5.3.3|p=284}}; {{Harvnb|Kagan|Jackson|1991|pp=21, 419}}; {{Harvnb|Jackson|Kagan|2006|p=S404}}.</ref> This model has an intuitive appeal; it is used in long-term forecasting, and was the basis of a series of circum-Pacific ([[Pacific Rim]]) forecasts in 1979 and 1989–1991.<ref>{{Harvnb|Kagan|Jackson|1991|pp=21, 419}}; {{Harvnb|McCann|Nishenko|Sykes|Krause|1979}}; {{Harvnb|Rong|Jackson|Kagan|2003}}.</ref>

However, some underlying assumptions about seismic gaps are now known to be incorrect. A close examination suggests that "there may be no information in seismic gaps about the time of occurrence or the magnitude of the next large event in the region";<ref>{{Harvnb|Lomnitz|Nava|1983}}.</ref> statistical tests of the circum-Pacific forecasts shows that the seismic gap model "did not forecast large earthquakes well".<ref>{{Harvnb|Rong|Jackson|Kagan|2003|p=23}}.</ref> Another study concluded that a long quiet period did not increase earthquake potential.<ref>{{Harvnb|Kagan|Jackson|1991|loc=Summary}}.</ref>