1. A magnitude (M) 5.9 earthquake struck eastern Afghanistan in the early morning hours of June 22
- The relatively moderate-magnitude earthquake struck at 1:42 am local time (20:54 UTC). It was a shallow earthquake with a depth of 10km beneath the surface. Seismic wave patterns indicate that this earthquake was predominately strike-slip faulting near the boundary of the Indian and Eurasian tectonic plates .
- The earthquake erupted 28 miles from the provincial capital of Khōst. Greater damage was reported in Patika, a neighboring province on the boarder of Afghanistan and Pakistan. Light shaking, Modified Mercalli Intensity (MMI) of 3.5, was felt in the capital of Kabul, nearly 100 miles away from the earthquake’s epicenter1.
- At least 1,000 fatalities and over 1,600 injuries have been reported, but the total is likely to increase as the damage is assessed.
2. A deadly earthquake event with many homes destroyed
- The June 22 event is the deadliest earthquake to hit this part of Afghanistan in more than a decade. Large earthquakes in this region are uncommon. There have only been seven M6.0 and larger earthquakes in this area since modern record keeping began1.
- According to the USGS PAGER, more than 35 million residents were exposed to ground shaking from this event. Approximately 1 million experienced moderate or greater shaking (> MMI 5)2.
© 2022 CoreLogic,Inc., All rights reserved.
- Economic losses from this event are expected to be minimal. The region of southeastern Afghanistan is primarily residential with high degrees of poverty and little development as it is rural and mountainous. The capital and economic center of Afghanistan, Kabul, did not experience severe enough ground shaking to generate material losses.
3. Why was this “moderately” strong earthquake so deadly?
- The high number of fatalities from this event are a result of the construction materials used for residential properties in the region and the time of day that the earthquake erupted.
- The population in these regions of Afghanistan and Pakistan generally reside in homes that are especially vulnerable to ground shaking. The predominant construction materials utilized are masonry materials like adobe blocks or mud. These materials are highly susceptible to the lateral forces that occur in buildings when they are shaken.
- Relative to more seismically hazardous parts of the globe with strong building codes and earthquake resilient construction, like Japan or California, a M5.9 earthquake is not severe enough cause wide-spread damage. In more developed nations, material building damage is not expected for earthquakes under M6.5. Modern building codes, such as the International Building Code, construction materials and practices are utilized to mitigate the effects of moderate to extreme ground shaking. The use of steel, either in the form of beams or rebar embedded in concrete walls, increases the overall ductility of a structure, which allows the building to absorb ground shaking motion. Many buildings contain moment-resisting frames where columns and beams can bend, but joints remain rigid, allowing for the entire frame to respond to lateral forces.
- Additionally, the earthquake erupted in the early morning hours. The probability that people were in their homes, and not in public spaces or buildings that may have been more earthquake resistant, is highest.
2022 CoreLogic, Inc. , All rights reserved.
[1] United States Geological Survey, 2022. https://earthquake.usgs.gov/earthquakes/eventpage/us7000hj3u/executive (Accessed June 23 2022)
[2] Yawar, Mohammad Yunus and Ahmad, Jibran, Afghanistan earthquake kills at least 1,000, toll expected to rise (Reuters, 2022).
