Earthquakes around the world

Last week was almost unusually quiet regarding earthquakes with no M6 or above worldwide.
In the usual area there were 0 out of 77 earthquakes worldwide equal or greater to 4.5 and 1883 out of 2214 quakes of all sizes.
Percentage: 85.0%
Last week I thought of finished in the post by saying stillness before the storm. And the M7.6 in Alaska did get the big blue marble rolling.
In the usual area there were 40 out of 136 earthquakes worldwide equal or greater to 4.5 and 2074 out of 2541 quakes of all sizes.
Percentage: 81.6%
Earthquakes 7 days to October 25th 2020.gif
 

5.5-magnitude quake hits 55 km NNE of Mamuju, Indonesia: USGS

October 28, 2020
NEW YORK, Oct. 27 (Xinhua) -- An earthquake with a magnitude of 5.5 jolted 55 km NNE of Mamuju, Indonesia at 19:43:52 GMT on Tuesday, the U.S. Geological Survey said.

The epicenter, with a depth of 17.38 km, was initially determined to be at 2.2321 degrees south latitude and 119.1095 degrees east longitude.

Moderate mag. 5.5 earthquake - 123 Km NNE of Atka, Alaska, USA

Date & time: Wednesday, 28 October 2020 04:13 UTC
Local time at epicenter: 27 Oct 4:13 pm (GMT -12)
Magnitude: 5.5
Depth: 233.2 km
Epicenter latitude / longitude: 53.2014°N / 173.4182°W
US.png
(Alaska, United States)
Nearest volcano: Korovin (105 km / 65 mi)

28.10.2020
 

5.6-magnitude quake hits 56 km WSW of Changuillo, Peru -- USGS

2020-10-28
BEIJING, Oct. 28 (Xinhua) -- An earthquake with a magnitude of 5.6 jolted 56 km WSW of Changuillo, Peru at 09:02 GMT on Wednesday, the U.S. Geological Survey said.

The epicenter, with a depth of 10.0 km, was initially determined to be at 14.9272 degrees south latitude and 75.6744 degrees west longitude.

Urgent: 5.8-magnitude quake hits 65 km SSW of Sola, Vanuatu: USGS

October 28, 2020
HONG KONG, Oct. 28 (Xinhua) -- An earthquake with a magnitude of 5.8 jolted 65 km SSW of Sola, Vanuatu at 14:12:56 GMT on Wednesday, the U.S. Geological Survey said.

The epicenter, with a depth of 178.34 km, was initially determined to be at 14.4415 degrees south latitude and 167.3852 degrees east longitude.

28.10.2020
 
Large 6.9/7.1 quake reported off the coast of Greece/Turkey (added: footage claiming to be from the recent quake of a building that has collapse, i'm guessing in Turkey):

It's not currently showing on USGS. But from CSEM:

Magnitude6.9
RegionDODECANESE ISLANDS, GREECE
Date time2020-10-30 11:51:24.2 UTC
Location37.89 N ; 26.79 E
Depth10 km

Macroseismic
Intensity
V Effects: Strong Shaking
Distances
62 km SSW of Karabağlar, Turkey / pop: 458,000 / local time: 14:51:24.2 2020-10-30

13 km NNE of Néon Karlovásion, Greece / pop: 6,700 / local time: 13:51:24.2 2020-10-30

Added: It's now up on USGS as an M7:
M 7.0 - 14 km NE of Néon Karlovásion, Greece
VIDYFI
VIIShakeMap
YELLOWPAGER
Time 2020-10-30 12:51:26 (UTC+01:00) Location 37.897°N 26.795°E Depth 10.0 km
 

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Tectonic Summary​

The October 30, 2020, M 7.0 earthquake offshore Samos Island, Greece, occurred as the result of normal faulting at a shallow crustal depth within the Eurasia tectonic plate in the eastern Aegean Sea. The focal mechanism solution indicates that the earthquake occurred on a moderately dipping normal fault striking either eastward or westward. This mechanism indicates north-south oriented extension that is common in the Aegean Sea. Tectonics in the region surrounding this earthquake are relatively complex; to the south, Africa (Nubia) lithosphere subducts northward beneath the Eurasia plate at the Hellenic Trench; to the east, the Anatolian microplate (part of Eurasia) moves in a general westward direction, driving right-lateral faulting along its northern boundary, the North Anatolian Fault, and left-lateral faulting in southeast Turkey. The Aegean Sea region, western Turkey, and southern Greece where the October 30 earthquake occurred overall experiences north-south extension that is driven by southward migration of the Hellenic Trench.

In western Turkey and the Aegean Sea region, historic earthquakes demonstrate a mixture of transtensional and extensional faulting focal mechanism solutions. The October 30, 2020 earthquake produced nearly pure normal faulting, and is broadly consistent with past earthquakes in the region. The location of the October 30, 2020 event is about 250 km north of the closest main plate boundary, where the Africa plate moves to the north at a rate of approximately 10 mm/yr with respect to Eurasia; this earthquake is thus considered an intraplate event.

While commonly plotted as points on maps, earthquakes of this size are more appropriately described as slip over a larger fault area. M7 normal faulting events typically have a fault area of 50 x 20 km.

The Aegean Sea frequently experiences moderate to large earthquakes, and the region within 250 km of the October 30, 2020 earthquake has hosted 29 other M 6+ events over the preceding 100 years. The largest instrumentally documented earthquake in the region was a M 7.7 earthquake in July 1956 between the islands of Naxos and Santorini (Thera), and southwest of the October 30, 2020 earthquake. The 1956 earthquake was the largest earthquake of the 20th century in Greece. As a result of this 1956 event, a M 7.2 aftershock occurred 13 minutes later with an accompanying large tsunami, 53 fatalities, 100 injuries, and extensive damage in Amorgos and nearby Santorini. More recently, on June 20 2017 a M 6.6 earthquake occurred southeast of the October 30, 2020 event near Bodrum, Turkey, and resulted in 2 fatalities and hundreds of injuries reported in Greece and Turkey.

 
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