The app explains: Why is Haiti prone to devastating earthquakes

The powerful earthquake that struck Haiti on Saturday killed hundreds of people and injured thousands more. This devastating move occurred nearly 11 years after the earthquake that killed tens of thousands, if not hundreds of thousands. About 100,000 buildings were destroyed in the 2010 earthquake.

Here’s a look at why Haiti has experienced so many devastating earthquakes throughout its history and why they have been so disastrous.

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What makes Haiti vulnerable to earthquakes?

The Earth’s crust is made up of moving tectonic plates. Haiti is located near the intersection of two of them: the North American Plate and the Caribbean Plate.

Multiple fault lines intersect between these plates or near the island of Hispaniola, which Haiti and the Dominican Republic share. What’s worse, though, is that not all of these fault lines behave the same way.

“Hispaniola is in a place where the plates go from crushing each other to sliding on top of each other,” said Rich Briggs, a research geologist at the US Geological Survey’s Geohazard Science Center.

“It’s like a stone stuck in the tracks of a sliding stone door,” he added. “It doesn’t move smoothly because it has many different forces on it.”

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What caused the last earthquake?

Saturday’s earthquake measuring 7.2 on the Richter scale likely occurred along the Enrico-Plantine Garden fault zone, which runs through the Tiburon Peninsula in southwest Haiti, according to the US Geological Survey (USGS).

This is the same fault zone where the devastating 2010 earthquake occurred. It is also considered the potential origin area for three other major earthquakes that rocked Haiti between 1751 and 1860, two of which destroyed the port. -O Prince, DC.

The earthquakes are the result of the slow movement of tectonic plates against each other, creating friction over time, said Gavin Hayes, scientific advisor for earthquakes and geological hazards at the USGS.

“This friction builds and builds, and eventually the stored pressure overcomes the friction,” Hayes said. “And that’s when the fault suddenly moves. This is an earthquake.”

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Why can earthquakes be so devastating in Haiti?

It’s a combination of factors including an active seismic zone, a population of 11 million, and buildings that are regularly designed to withstand hurricanes, not earthquakes.

Concrete structures and concrete blocks can withstand high winds, but are susceptible to damage or collapse upon vibration. Poor building practices also play a role.

The 2010 earthquake struck near Port-au-Prince, a densely populated area, and caused widespread destruction. The Haitian government put the death toll above 300,000, although a report requested by the United States government put the death toll between 46,000 and 85,000.

“I think it’s important to realize that there are no natural disasters,” said Wendy Bohon, a geologist with the Integrated Research Institutions for Seismology. “What you have is a natural hazard interfering with a weak system.”

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What does the future hold?

Geologists say they cannot predict the next earthquake.

“But we know that earthquakes like this can cause tremors of similar size in the next section of the fault,” said Hayes of the USGS. “And it presents a fairly significant danger in places where there are no building practices that would allow movement resistance.”

Building more earthquake-resistant buildings is on hold in Haiti, the poorest country in the Western Hemisphere.

Prior to Saturday’s earthquake, Haiti had not fully recovered from the 2010 earthquake and Hurricane Matthew in 2016. In addition, President Jovenel Moise was assassinated last month, causing political chaos in the country.

Mark Schuller, professor of anthropology and nonprofit studies at Universidad del Norte, said that although there are some success stories of Haitians constructing buildings with the most earthquake-resistant structures, the country lacks a central effort to do so.

The Haitian government is getting weaker and weaker, while NGOs are focusing on their own projects.

“There is technical knowledge in Haiti. There are trained architects. There are city planners. That is not the problem,” Schuller said.