Low seismicity and damage in April 2022. Casualties were mostly related to induced earthquakes and landslides.

General summary:

In April 2022 the number of damaging earthquakes remained below average as well as the general earthquake activity. 20 cases of damaging earthquakes have been detected during this month of which two can be directly linked to human activity. Eleven casualties and 23 injuries are related to these earthquakes, 5000 buildings were damaged and around 2000 people were displaced. These losses are significantly lower than in the previous months.

Damaging earthquakes:

First considering earthquakes of tectonic origin only, of these 16 events the M5.7 earthquake in Bosnia-Herzegowina on April 22nd was the most significant. It occurred in the south of the country close to Croatian border and was felt in many parts of Balkan peninsula as well as in wide parts of Italy, Austria and south-eastern Germany. According to the latest reports, around 1100 buildings were damaged in Bosnia-Herzegowina and Croatia, some of the severely. Small landslides and rockfalls were triggered by this earthquake and caused additional damage. In one case, a falling boulder hit a residential house, killed one resident and injured two others. Additional damage was caused by a 4.8 aftershock two days later.

1660 buildings suffered damage due to a magnitude 5.1 earthquake in the Chinese province Sichuan on April 6th. More than 1000 people were displaced. The quake affected the southern part of Sichuan which was frequently hit by damaging earthquakes over the past few years, an increase of seismicity that can be partially related to mining and hydraulic fracturing. However, there are no indicators that this earthquake is also related to human activity.

In southern Peru, a Magnitude 3.8 quake on April 10th was said to have destroyed several homes with at least 200 people being displaced. A later issued report however says that these losses were not confirmed my local official sources. It remains uncertain whether the first official report of these losses is true.

Tsunamis:

No earthquake-related tsunami was observed in April 2022.

Landslides:

Except the landslide-related losses after the Bosnia-Herzegowina earthquake and its aftershocks, landslides were reported after two earthquakes: The M5.1 Sichuan earthquake and a small, shallow 3.8 near the Ecuadorian capital Quito which both have affected road traffic without significant losses.

Volcanic Eruption:

No damaging earthquakes were associated with volcanic activity in April 2022. However, the earthquake swarm on the Azores Island Sao Jorge that began in March continued with lower intensity.

Induced earthquakes:

Poland was again affected by mining-induced earthquakes. Two of them lead to dangerous mining collapses. In one case, ten miners were killed following a magnitude 2.8 mining shock in Silesia on April 23rd. Additionally, a smaller mining accident with one injured person followed a M4.5 quake on April 27th in Lower Silesia.

Central Vietnam was hit by several earthquakes over the past few months, the strongest ones on April 18th with M4.6 and M4.3. This earthquake sequence is related to the impoundment of a nearby reservoir. However, although no damage was reported from those mainshocks, damage to schools and homes has been reported from the continuous smaller quakes that happened since January.

Another damaging earthquake was also observed in the northern Netherlands where gas production has caused hundreds of small and damaging earthquakes over the past decades. The new one, M2.7 on April 1st, was followed by around 250 damage claims. As usual after these quakes, most of the damage claims are getting compensated without being confirmed due to legal reasons.

Other earthquakes:

Only eight earthquakes larger than Magnitude 6 occurred during April 2022. Of these, only the M6.7 quake off the coast of Nicaragua on April 21st, also the strongest earthquake of the month, caused minor damage.