**7. Time series and strength of the three earthquake groups**

In Section 6 the spatial features of the located aftershocks were analyzed. In this section the time series and the strength of the three earthquake groups are very briefly analyzed. After the events were sorted and plotted in **Figure 9**, we found in the upper panel (a), the right group (see **Figure 2**) there are 23 events, 6 of them with magnitude ≥4.0; in (b), the left group, 26 events, 2 of them with magnitude ≥4.0; and in (c), the bottom group, 22 events, only 1 of them with magnitude ≥4.0. Rough calculations show that the energy released in the right group is more 10 times than that in the left group; more 200 times than that in the bottom group. A common feature is that after 7 years since the mainshock, aftershocks still occurred in all groups.

#### **Figure 9.**

*Time series and strength of the 3 earthquake groups. Each vertical line segment stands for an earthquake; the length shows the magnitude; the position along horizontal axis shows the origin time (the origin time of the mainshock was set to 0). (a) In the right group (see* **Figure 2***) there are 23 events, 6 of them with magnitude* ≥ *4.0. (b) In the left group, 26 events, 2 of them with magnitude* ≥ *4.0. (c) In the bottom group, 22 events, 1 of them with magnitude* ≥ *4.0. All the origin times of the earthquakes were converted into Unix epoch times, and the origin time of the mainshock was set to 0. The time duration is from 1982-0109 12:53 52 to 1989–0109 12:53 52.*

*Locations of the 1982 Miramichi (Canada) Aftershocks: Implication of Two Rupture Regions… DOI: http://dx.doi.org/10.5772/intechopen.108195*
