Three big earthquakes but several disasters from smaller quakes. An active month with many losses.

General summary:

The year 2023 started with some seismically relatively active weeks, not only in terms of earthquake damage: Three earthquakes larger than magnitude 7 in Indonesia (2) and Vanuatu (1) and nine others larger than Magnitude 6 were detected. While all M7 events caused at least minor damage, most of the M6 quakes remained completely harmless. However: Bigger earthquake disasters of the past month originated from smaller events. In total, 35 damaging earthquakes were registered, leading to four casualties, 1476 injuries and 18,000 damaged buildings. 98.2% of all earthquake losses this month resulted from earthquakes with M<6.

Damaging earthquakes:

Iran has been the most earthquake-affected country in January. Main reason was an ongoing earthquake sequence in the northwestern region of West Azerbaijan. Near the city of Khoy, which was previously affected last October, two strong and hundreds of small earthquakes happened, leaving destruction, frightened residents and many injures. The strongest quake with M5.9 on January 28th also caused three casualties, left 1174 people injured and more than 26,000 homeless. Damage assessment is still ongoing. Initial reports indicate that at least 1800 buildings were destroyed, 7500 more damaged. A magnitude 5.6 quake one week earlier caused 252 injuries and left 16000 people homeless while around 5000 buildings were affected. With impact values of 2.95 and 2.70, the Khoy earthquakes are the most destructive quakes of 2023 so far.

Another earthquake disaster hit the Far Western region of Nepal. A 5.6 quake struck the area on January 24th. One person was killed by triggered rockfalls (also at least 40 sheep), at least four more were injured. Preliminary damage reports say that 575 houses were damaged to various degree, leaving 165 families homeless. While the earthquake was also felt in large parts of India, no damage has been confirmed from there. However, some media reports claim that a building collapse in Lucknow which caused several casualties is related to the earthquake. This cannot be confirmed and Risklayer consideres it as highly unlikely. Therefore, we do not include this in our Earthquake Impact Database.

For multiple days in mid-January, the border region of Guatemala and El Salvador was hit by a moderate earthquake swarm with strongest events reaching Magnitude 5.2. These very superficial events left major damage in both countries, especially in Ahuachapan area of El Salvador. In total, more than 1300 houses were damaged by these quakes. Due to the repeating shaking, more than 60% of the affected buildings became uninhabitable, displacing around 3000 people. Four people in El Salvador were also slightly injured. This earthquake sequence has a tectonic origin and is not related to any volcanic activity. Minor earthquakes are still ongoing but frequency and intensity of these events has significantly decreased by now.

With Magnitude 7.6, the major earthquake in southern Indonesia on January 9th became the strongest quake of the month and, most likely, one of the biggest quakes of the year 2023. However, damage was limited due to the intermediate depth and offshore epicenter location. Shaking was felt in many parts of southern Indonesia and northern Australia but damage was only caused in Maluku and Tanimbar regencies. In total, 11 people were injured, 400 displaced and 1500 buildings damaged, most of them only slightly. A small tsunami was caused but without leaving any damage. Early media reports indicated a fatality from this event, which was quickly denied by Disaster Management Agency. The passed person died during a diving accident that was not related to the quake.

Also the second strongest quake of the month affected Indonesia: It happened north of Halmahera island on January 18th, leaving minor damage on nearby Morotai island. Along the northern coast of Halmahera, several buildings and boats were destroyed on the same day by a so-called "tidal wave" which was said to be associated with the earthquake, according to local media reports. After evaluation of this incident, Risklayer consideres a relation as highly unlikely. The "tidal wave" most likely results from meteorological phenomena.

The third M7 quake affected parts of Vanuatu on January 8th. The epicenter was located near Sanma island and very strong shaking was felt across the island. However, there were only limited reliable reports of damage, indicating some cracked buildings. False claims of several destroyed buildings appeard in some international media outlets which trusted in fake pictures posted by a local source in Social Media. These pictures didn't show the effects of the quake but the destruction after a Tropical Cyclone in 2015.

Tsunamis:

A 9 cm tsunami was detected after the M7.6 event in Southern Indonesia. No more earthquake-related tsunamis were detected. A small volcanic tsunami followed the eruption of Epi volcano, Vanuatu on January 31st.

Volcanic Eruption:

No volcanic activity was associated with damaging earthquakes.

Landslides:

11 damaging earthquakes were associated with landslides, rockfalls or lateral spreading. Except the earlier discussed Nepal quake, no quake-landslides caused harm to people or buildings. Landslide damage to roads resulted from the M7.6 quake in Indonesia, a 4.8 quake on the Philippines on January 18th, a 5.6 quake in China on January 25th and the M5.9 Iran earthquake on January 28th. Additionally, a 5.3 earthquake on Cabo Verde Islands on January 26th triggered rockfalls that affected a road but didn't cause any building damage. Lateral spreading from a very shallow M5.1 on New Zealands North Island on January 3rd affected some farm land.

Induced earthquakes:

No damaging induced earthquakes were detected in January.

Other earthquakes:

According to reports of locals, an earthquake destroyed several houses in western DR Congo on January 18th. However, no seismic network has detected any signal of seismicity from this area although it is important to notice that the closest open station is located in Uganda. Small earthquakes in this area can remain undetected. Reports of damage were very vague which makes it very difficult to evaluate if such an earthquake can be the origin. It remains uncertain. An earthquake is plausible, either is a landslide.

Damaging earthquakes in January 2023 and previous years.

Impact statistics January 2023

Damaging earthquakes: 35 (34 tectonic, 0 induced, 0 volcano-related, 1 unknown origin)
Affected countries: Indonesia (6 events), Iran (4), Greece (3), China, Peru, Philippines, China (2),Albania, Australia, DR Congo, El Salvador, France, Guatemala, Italy, Morocco, Nepal, New Zealand, Pakistan, Russia, Ukraine, Vanuatu
Casualties: 4
Injuries: 1476
People displaced: ~52000
Buildings damaged: ~15000
Buildings destroyed: ~3100