Magnitude 7.2 Earthquake in Haiti
The USGS has up-to-date details on the August 14, 2021 event
Additional Aftershock Information
More aftershocks than usual will continue to occur in the southern peninsula of Haiti. Aftershocks will decrease in frequency in the days, months, and years after the magnitude 7.2 main seismic event. During the first weeks there are likely to be hundreds of aftershocks large enough to be felt in this area.
Larger aftershocks could cause additional damage, especially in weakened structures. Several magnitude 5 and larger aftershocks have occurred already, and it is likely that there will be more earthquakes of this size over the next week, month, and beyond.
About 1 in 20 mainshocks, like the 7.2, are followed by a similar-sized or larger quake, within the first week. This chance goes down with time however, and large aftershocks can occur even months after the mainshock.
USGS scientists and partner agencies continue to monitor the situation and gather more information about this aftershock sequence.
Additionally, USGS landslide scientists have mapped almost 1,600 landslides in the country so far. More information will be published here once it's available.
What To Do If Your Area Experiences More Seismic Activity
Advice on what to do during an earthquake varies depending on the country. According to GeoHazards International, if you currently live in Haiti and are inside a building when you feel an earthquake, this is what to do:
- If you are inside and can easily get out, evacuate to a safe open place covering your head and your neck. Head to an open space where walls and electric poles cannot fall on you.
- If you can’t evacuate, drop where you are, cover your head and neck with one arm and get under a sturdy table, and then hold on to the table legs until the shaking stops.
- Stay away from landslide areas and hillsides with cracks, as aftershocks can cause new landslides and existing landslides to move again.
Haiti’s earthquake event on August 14 was centered 13 kilometers (just over eight miles) south-southeast of Petit Troup de Nippes, and was widely felt across the region including all of Hispaniola (Haiti and Dominican Republic) and the islands of Jamaica, Cuba, and Puerto Rico, with estimates of over 1 million people exposed to very strong or severe shaking levels.
Follow-on Seismic Activity
Aftershocks are expected to continue to occur in the southern peninsula of Haiti, mostly in the vicinity of the magnitude 7.2 mainshock. Already, there have been several magnitude 5 and larger aftershocks, and it is likely that there will be more over the next week, month, and beyond. There is a chance for larger aftershocks to cause additional damage, especially in weakened structures.
There is a very small chance that this earthquake could be part of a sequence that includes an even larger quake (about 1 in 20 earthquakes occur as part of a sequence).
Landslide and Hurricane Risk
Landslides triggered by this earthquake are estimated to be significant in number and over a wide area, and there are a significant number of people living near areas that could have produced landslides.
Preliminary landslide mapping from post-event satellite imagery revealed at least 150 landslides west of the town of L’Asile in Département des Nippes and hundreds of landslides in the mountains and south of Beaumont in Department de la Grand'Anse. Cloud cover obscured much of the satellite imagery, limiting the review area.
Intense precipitation from incoming Tropical Storm Grace could mobilize sediment from earthquake-triggered landslides into debris flows and could cause additional landslides.
Direct fatalities and damage from landslides are possible, roads through mountainous areas may be obstructed, and streams could be dammed. Overland access to the western affected areas such as Les Cayes from the east may be difficult.
The USGS will continue to monitor the situation and publish further updates as we gather more information about this earthquake and the ongoing geologic hazards.
Original Story: 8/14/21
The earthquake occurred 78 miles (125 km) west of the capital city of Port-au-Prince at a depth of 6.2 miles (10 kilometers).
The preliminary USGS PAGER report shows RED for shaking-related fatalities and economic losses – indicating high casualties are probable and significant damage is likely. Given the likely impact of this event, a significant international response seems likely.
Local earthquake information: Ayiti-SEISMES | Accueil (unice.fr)
The earthquake occurred in Haiti's southwest peninsula, about 60 miles (100 km) west of the devastating January 2010 M 7.0 earthquake. Perceived shaking for today’s earthquake was very strong to severe at the epicenter and weak to light in Port-au-Prince. USGS scientists expect that this event will trigger aftershocks, but these will decrease in frequency over time.
Like the 2010 event, the faulting mechanism for this earthquake indicates oblique thrust faulting along the Enriquillo-Plantain Garden fault zone, the major fault structure and microplate boundary in the region.
Visit the USGS earthquake event page for more information. For estimates of casualties and damage, visit the USGS Prompt Assessment of Global Earthquakes for Response (PAGER) website.
If you felt this earthquake, report your experience on the “USGS Did You Feel It?” website for this event.
For information about tsunami watches, warnings or advisories, visit the National Oceanic and Atmospheric Administration (NOAA) tsunami website.
The USGS operates a 24/7 National Earthquake Information Center in Colorado that can be reached for more information at 303-273-8500.
Learn more about the USGS Earthquake Hazards Program.
We will update this story if more information becomes available.