These Small, Cheap Devices Help Monitor Haiti’s Earthquakes

When a 7.0 magnitude earthquake shook Haiti in 2010 and killed an estimated 200,000 people, only one seismometer was in operation in the country. The tremor quickly knocked out the high school teaching instrument, the seismometer, and recorded some useful data.

Weeks passed before foreign seismologists could travel to the disaster area, and then months passed before the portable seismometers they installed, which recorded enough aftershocks to illuminate a torn fault.

A magnitude 7.2 earthquake shook Haiti last August. Conventional seismometers installed after the 2010 earthquake were not working at the time. But a number of small, inexpensive instruments operated by civilian scientists were able to capture the seismic waves, giving researchers a quicker view of where the Earth had broken deeper underground and the value of listing enthusiasts interested in science. (The death toll from the quake was about 2,200, much lower than in 2010 because the epicenter was in a more rural part of the country.)

“In 2021, we had that information in real time,” said Eric Klais, a geophysicist from Cole Normal Superior in Paris who has been studying Caribbean tectonics for over 30 years. “So that’s a big difference.”

Writing in an article published in the Science Journal on Thursday, Dr. Calais and his colleagues described what the civic science seismometers revealed about the August earthquake. The catastrophic earthquake of 2010 caused the same fault to erupt about 40 miles, but farther west. The data also revealed some surprises, Dr. “At the eastern end of this segment, there was no defect, where two tectonic plates were sliding behind each other,” said Calais. Instead, the two plates were also being pushed together, with the north one sliding over the south top.

“If we hadn’t had aftershocks delivered, we wouldn’t have been able to put proper geometry into our models,” said Dr. Said Klais. “Then our assessment of what happened will be wrong.”

The Caribbean is an area of ​​seismic risk that is sometimes overlooked, with active volcanoes and seismic defects. Susan E., a seismologist with the United States Geological Survey. “The Caribbean has its own small-scale Ring of Fire,” Hogg said. “It’s like a small Pacific rim.”

But tectonic plates are breaking together at a slower rate, and large earthquakes are rare. The region was relatively quiet in the late 20th century. “People were happy about it,” said Dr. Hough said. “The 2010 earthquake did not surprise any of the world’s earthquake professionals, but it did surprise many who were not aware of the scientific results.”

Dr. Hogg and Drs. Calais was one of the seismologists who traveled to Haiti in 2010. After the earthquake that year, international organizations provided funding to set up a traditional seismometer in Haiti, which cost thousands of dollars. A magnitude 7.2 earthquake shook the region in August. 14, none of Haiti’s traditional seismometers were working, although seismometers were collecting data at the United States Embassy.

“It is difficult, if not impossible, to operate a traditional type of advanced seismic network in Haiti,” he said. Hough said. “They don’t have a functional power grid, for example, leave reliable internet everywhere.”

Haiti remains politically unstable, suffers from widespread poverty and is vulnerable to natural disasters. The president, Jovenel Moyes, was assassinated a month before the August earthquake. A few days after the earthquake, a tropical storm, Grace, passed over the island.

In 2018, at the Seismology Conference in Malta, Dr. Calais met Brandon Christensen, chief executive of Raspberry Shake, a Panama-based company that connects a small, inexpensive computer called the Raspberry Pi to a small, inexpensive device used by the oil and natural gas industries to measure small ground speeds. A seismometer that costs a few hundred dollars instead of thousands of dollars.

Raspberry shake devices, smaller than a breadbox, can measure minute movements of the ground, albeit in a smaller range of frequencies than modern conventional seismometers. But they do not need to be anchored on the ground and only need a power outlet and internet connection.

“I immediately thought the level of simplicity of the device was such that it would have a better chance of surviving in Haiti in the long run, meaning no maintenance,” said Dr. Calais recalled. He used the little surviving grant money to buy five of them, and, with colleagues in Haiti, he began looking for volunteers who were willing to put one in their home or office. Since then the network has expanded to about 15 devices.

Dr. Calais said Haiti data showed that while raspberry shakes were not as capable as traditional seismometers, they did make scientifically valuable measurements. “They’re capable of working when it comes to recording even the smallest aftershocks,” he said.

Raspberry Shakes, however, is not free from Haiti’s infrastructure limitations. When the main quake struck last August, only one in three near the epicenter was operational.

The closest device to the epicenter was offline, as the host let its Internet service down. But he renewed it soon after he felt the tremor. “We have to accept this kind of problem,” said Dr. Said Klais. “Internet and power are never provided in Haiti.”

Researchers were also able to add three raspberry shakes to the area, and all six measured more than a thousand aftershocks that arrived the following week.

Seismic data published online only Dr. Calais’s inspiration for setting up a raspberry shake network. It is also to spread knowledge about the dangers of earthquakes among the volunteers hosting Raspberry Shakes and others in Haiti.

Steve J., a geophysicist and author of the science paper at the State University of Haiti. “We want to force some people in the community to act differently,” Smith said.

Dr. Born in Haiti, Smith was studying to become a civil engineer, but after the 2010 earthquake she changed her field and completed her doctorate at Purdue University. Calais, who was a professor there at the time.

Raspberry Shakes, which grew out of the Kickstarter project in 2016, is now established worldwide, with similar networks in France, Oklahoma and Haiti in Nepal. More than 1,600 devices report their data on the company’s website. “They’re popping up everywhere,” Mr. Said Christensen.

With adequate equipment deployed, “you can start doing magical things like early warning of an earthquake,” Mr. Said Christensen. “You can start mapping and finding earthquakes in places that people think are asymmetrical or you can start mapping faults.”

Some research does not even include earthquakes. In a July 2020 paper published in Science, scientists used data from 300 seismic stations, including 65 raspberry shakes, to observe the global silence of noise resulting from trains, planes, factories and other man-made vibrations. Nationwide epidemic of covid 19.

“Without the raspberry shake, that would be a very difficult question to answer,” Mr. Said Christensen. “The reason is that most seismographs, which are professional grades, are installed in mountains and places that are really quiet, away from humans.”

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