Multiple earthquake sequences, destructive events and volcanic effects led to more than 30,000 damaged buildings.
Multiple strong earthquake and earthquake sequences with damaging effects have been recorded in July 2022, resulting in several casualties and significant damage. Of these, the Mw7.0 on Luzon, Philippines became one of the most destructive earthquakes of the year so far. In total, 29 damaging earthquakes occurred that month and resulted in 19 casualties and 554 injuries. Approx. 60,000 people were displaced and 33,000 structures damaged or destroyed. Damaging earthquakes affected 21 countries.
Many parts of Luzon suffered from the devastating and shallow Mw7.0 on July 27th. Although the extent of the damage is still being assessed, preliminary statistics indicate the second-most devastating earthquake of the year in sense of affected structures. 26,000 buildings in multiple provinces of north-western Luzon suffered damage or destruction. Damaging effects were even reported from the capital Manila, where two hospitals were affected. However, despite the rather destructive effects, death toll remained relatively low. Ten people died, four of them in coseismic landslides. Around 400 other people suffered injuries and 50,000 people were displaced (as of August 1st).
The earthquake resulted from a complex rupture of a shallow fault zone that crosses the mountain range of western Luzon. Shallow faulting in a mountainous environment led to widespread landslides. The National Disaster Risk Reduction and Management Council (NDRRMC) of the Philippines registered at least nine damaging landslides. Of those at least one fatal and one with injuries. Additionally, strong aftershocks are still ongoing with a large Mw5.5 happening on July 31st, bearing the potential for further damage.
A complex set of fore-, main- and aftershocks has also affected southern Iran. In the province of Hormozgan on the southern coast, at least three quakes of Magnitude 6 and larger hit on July 1st, leading to widespread destruction in nearby villages. It followed another damaging earthquake sequence one week earlier just to the west. Liquefaction significantly affected wide areas, including a large shrimp farm. Shocks of the mainshocks were felt as far as Dubai and Qatar. Strong aftershocks up to Magnitude 5.8 followed over the next weeks. In total, these earthquake sequence resulted in seven casualties, 110 injuries and damage to at least 3000 structures.
Another earthquake sequence has affected the Peruvian province of Moquegua. The strongest quake on July 12th reached Magnitude 5.4. Three people were injured and significant damage was caused in nearby villages. 227 houses were fully destroyed while 751 buildings suffered minor damage. More than 500 people were left homeless. Additionally, several landslides occurred, leading to blockage of roads. The quakes resulted from a shallow fault near the city of Arequipa.
Destruction of at least 600 buildings resulted from a strong M5.1 aftershock that has hit south-eastern Afghanistan on July 18th. At least 20 people were injured but no new casualties have been reported. However, this event worsened the disaster situation that followed the devastating M5.9 on June 21st that killed 1079 people in Afghanistan and Pakistan.
No earthquake-related tsunami was observed in July 2022.
A strong earthquake resulting from magmatic ground deformation has caused severe damage in Northern Ecuador and bordering parts of Colombia. The M5.7 event on July 25th destroyed 225 houses and damaged more than 500 more. Nine people in Ecuador were injured and several landslides reported. The nearby volcano Chiles-Cerro Negro has been rumbling for several years, leading to strong seismicity previously in 2017. Since April, significant ground uplift is ongoing with significant level of small seismicity. However, the July 25th event was by far the strongest. While smaller quakes continued, volcanologists of both countries warned that an eruption might occur in the near future and set the alert level to yellow. Since the main cones Chiles and Cerro Negro are thought to be monogenetic and ground uplift mostly concentrated near the Pleistocene-pliocene Potrerillos Caldera, the theoretical sites of a possible eruption cover a broad area with many people possibly affected.
Less people affected but possibly more international attention could follow an ongoing earthquake sequence in south-western Iceland. Near the site of last year’s Fagradalsfjall eruption, a new magmatic intrusion has been observed on July 30th. Following two days of very high seismicity and possible strong ground deformation (satellite data confirmation still pending), a Magnitude 5.4 has been triggered near the town of Grindavik in the evening of July 31st, 20 km south-west of the magmatic dike. Due to the extreme shallow depth (less than 2 km), very strong shaking was felt there and some buildings suffered damage. Rockfall was also reported from nearby hills. With ongoing magma movement, more strong quakes could be expected on Reykjanes peninsula.
Minor rockfall on roads was reported from a shallow 6.2 earthquake near the coast of Antofagasta, Chile on July 28th. However, one person was injured in this quake but damage from this event was limited. Despite this and previously mentioned events, no significant co-seismic landslides were detected.
Although the exact origin of this quake remains unknown by now, a magnitude 4.4 event hit the Russian Oblast Kemerowo on July 5th, leading to a mining accident where at least two miners were killed and two other injuries. We classify this event as possibly induced by mining activity. However, tectonic earthquakes have also been observed there in the past.
Another case of “possibly induced earthquake” happened in Chhattisgarh, India on July 28th. An uncommon M4.6 affected the mining region. Five miners were injured by a rockfall in a mine. However, no building damage on the surface has been confirmed. Earlier this year, a 4.3 quake has affected the same area, causing minor damage to buildings. The Indian Seismological Department gives the depth of the mainshock with 16 km, which would clearly indicate a tectonic origin. Previously, depth solutions of this agency have been rather poor though.
Another earthquake sequence of tectonic origin affected eastern Myanmar in the second half of July. The strongest quake with M5.9 has significantly damaged several buildings in nearby village but only limited information are available from this area due to the political situation. The southern coast of Pakistan was hit by a shallow M5.5 earthquake on July 31st. Damage and partial collapse of some buildings due to the quake was reported from the city of Pasni that previously suffered from severe floodings. However, no details are available at the time of this publication. Germany recorded its first earthquake damage of the year. A magnitude 4.1 quake, the strongest in Germany since 2014, was felt widely in south-western parts of the country on July 9th. At least 11 buildings were slightly damaged. One of the strongest earthquakes in decades hit the norwegian islands of Svalbard on July 18th (M5.9). Although no damage was caused, the quake was felt widely.