# Minor mag. 1.0 earthquake - Italy: 4 Km NE Opi (AQ) on Monday, Sep 20, 2021 10:55 pm (GMT +2) - writeAge(1632171324)

Quakes around its antipode during the following 3 days
Check different time intervals: 24 hours | 2 days
Date & time: 20 Sep 2021 20:55:24 UTC -
Local time at epicenter: Monday, Sep 20, 2021 10:55 pm (GMT +2)
Magnitude: 1
Depth: 15 km
Epicenter latitude / longitude: 41.8102°N / 13.857°E (Italy)
Antipode latitude / longitude: 41.81°S / 166.143°W
Primary data source: INGV (Istituto Nazionale di Geofisica e Vulcanologia)
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## Quakes within 30 degrees from seismic antipode up to 3 days after the quake

The area around the antipode is marked with the big circle on the map.
The total number of quakes that occurred within 3 days around the antipode of the quake was 12. This is compared to the average number of 17.86 quakes during preceding intervals of 3 days with a standard deviation (σ) of 33.9, calculated by analzing all 100 preceding intervals of 3 days for the same region.
Interpretation:
Note: At a magnitude of 1.0, it is unlikely that this quake could affect areas around its antipode. If an increase or decrease of quake is detected, it is likely caused by other factors.
There is no significant variation in the number of quakes that occurred around the antipode within 3 days.
 Mag class Total # Average σ Observed deviation 6+ 0 0.3 1.3 -0.3 (-0.2σ) 5+ 3 3.5 8.9 -0.5 (-0.1σ) 4+ 8 8.2 9 -0.2 (-0σ) 3+ 1 5.8 17.7 -4.8 (-0.3σ) Total 12 17.86 33.9 -5.9 (-0.2σ)
Explanation:
BLACK = Number of quakes within normal statistical range
RED = Significantly lower than normal number of quakes
GREEN = Significantly higher than normal number of quakes

## List of quakes

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Showing quakes magnitude 3.0 or higher (total: 12).
 Date and time MagDepth Location Details 21 Sep 2021 15:30:09 GMT(19 hours after quake) 4.810 km 121 Km ENE of ‘Ohonua, Tonga [Show on map] More 22 Sep 2021 08:36:39 GMT(1 day 12 hours after quake) 5.012 km New Zealand [Show on map] More 22 Sep 2021 14:01:09 GMT(1 day 17 hours after quake) 4.4515 km Fiji: New Zealand [Show on map] More 22 Sep 2021 16:28:33 GMT(1 day 20 hours after quake) 4.733 km New Zealand [Show on map] More 22 Sep 2021 17:33:00 GMT(1 day 21 hours after quake) 5.010 km New Zealand [Show on map] More 22 Sep 2021 17:44:29 GMT(1 day 21 hours after quake) 4.510 km Kermadec Islands, New Zealand [Show on map] More 22 Sep 2021 19:57:25 GMT(1 day 23 hours after quake) 4.8368 km New Zealand: Kermadec Islands Region [Show on map] More 22 Sep 2021 19:57:27 GMT(1 day 23 hours after quake) 5.6383 km New Zealand [Show on map] More 23 Sep 2021 02:03:50 GMT(2 days after quake) 4.5395 km South of the Fiji Islands [Show on map] More 23 Sep 2021 08:36:12 GMT(2 days after quake) 4.8549 km South of Fiji Islands [Show on map] More 23 Sep 2021 08:36:27 GMT(2 days after quake) 4.8586 km New Zealand [Show on map] More 23 Sep 2021 12:39:17 GMT(3 days after quake) 3.033 km New Zealand [Show on map] More
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