Turkey was hit by an earthquake that tells us something about the science of forecasting earthquakes

A 20-Year-Old Earthquake on Turkey’s East Anatolian Fault Line Revealed by John McCloskey

Two decades ago, John McCloskey drew a red line on a map of southeastern Turkey to indicate where a large earthquake would likely strike. The only question was when.

The larger the mainshock, the bigger the aftershocks and the less severe they are as time goes on. While the original quake has been felt along its fault line as well as at a different fault line connecting to the north, there has also been a magnitude 7.5 after shock that appears to have hit. Alice Gabriel, a seismologist at the Scripps Institution of Oceanography, says that there is a complicated system of faults. That complicates things so that something else doesn’t stay there. It may have been that the stress that led to the 7.5 quake had been building for some time, and the jolt from the mainshock unleashed it. “It sort of advanced its clock a bit, so that it had the large earthquake that it would have eventually anyway, probably a bit sooner,” says Austin Elliott, an earthquake geologist at the United States Geological Survey. There’s nothing that makes the earthquakes distinct. The stress in the earth’s crust is changed by an earthquake so large, it increases the rate of earthquakes in the area.

This is unlike the Ring of Fire, which runs along the west coast of the United States. Subduction is the most likely cause of earthquakes in this zone.

A group of people used this technique in 2002 to figure out which parts of the East Anatolian fault were stressed. With the help of historical records, the team incorporated the stress changes caused by ten earthquakes since 1822 into a model of ongoing plate movement. The location and length of the fault that caused a large earthquake in February has been suggested by modelling to be at heightened risk of giving way in the future. The team knew that it would be devastating and forecast a magnitude of 7.3 or higher. “The correspondence is remarkable,” McCloskey says.

The death toll from the earthquake is expected to increase further, with rescuers digging through rubble to find survivors. Nature spoke to four researchers about the seismic activity in the region and what the next few days will bring.

Earthquake-Shattered Buildings in Syria: The Effects of the Fourth Anatolian Fault on Urban Living and Disaster Management in Turkey

The North and the East Anatolian Faults are both located on the Anatolian plate. The tectonic plate that carries Arabia, including Syria, is moving northwards and colliding with the southern rim of Eurasia, which is squeezing Turkey out towards the west, says David Rothery, a geoscientist at the Open University in Milton Keynes, UK. Turkey is moving west at an average of 2 centimetres per year. Half the length of the fault has been struck by earthquakes.

In a study1 published last March in Soil Dynamics and Earthquake Engineering, Arzu Arslan Kelam at the Middle East Technical University, Ankara, and her colleagues suggested that the centre of the city of Gaziantep would experience medium-to-severe damage from a magnitude-6.5 earthquake. Most buildings are constructed of brick and are close to each other.

Since the beginning of the conflict more than 11 years ago, the building standards in Syria have become impossible to enforce. The buildings collapsed after the earthquake in Syria’s northwestern regions. Some war-damaged buildings in Syria have been rebuilt using low-quality materials or “whatever materials are available”, says Rothery. “They might have fallen down more readily than things that were built at somewhat greater expense. We’ve yet to find out,” he adds.

With snow and scattered showers in the region, those trapped underneath the rubble are at risk of getting cold, especially since they’ve already gone days without food and water. The residents have been asked to leave their buildings for their own safety.

The chances of finding survivors diminish with every hour, even though rescue teams are still looking for signs of life beneath the rubble of collapsed buildings.

A number of factors have contributed to making this earthquake so lethal. One of them is the time of day it occurred. Many people who were in their beds when the earthquake struck are now trapped under the rubble of their homes.

The quality of buildings, codes and construction in Turkey, from earthquake reconstruction to reconstruction and reconstruction: a comment on CNN’s Anisotropy

Additionally, with a cold and wet weather system moving through the region, poor conditions have made reaching affected areas trickier, and rescue and recovery efforts on both sides of the border significantly more challenging once teams have arrived.

According to CNN, the images of widespread destruction and debris indicates there are highly variable qualities of designs and construction. The types of structural failures following an earthquake are usually partial collapses. He said that he tried to avoid total collapses in both codes and the actual design.

“If you are not designing these structures for the seismic intensity that they may face in their design life, these structures may not perform well,” said Jaiswal.

Many of the buildings that have collapsed may have been built before 1999, according to Erdik. He added there also would have been instances where some buildings didn’t conform to code.

The codes in Turkey are very modern, similar to US codes, but there is an issue of codes Complying that we have tried to tackle with legal and administrative procedures. he explained. The permits and controls for design and construction are given by the cities. But then again, there are things that are lacking.”

Why are people dead after a deep earthquake? The earthquake-turkey-syria why death is the biggest enemy in Turkey and Syria

Despite the mounting challenges, a structural engineer and humanitarian coordinator urged rescuers not to abandon hope as survivors could be found up to “weeks” after the massive earthquake hit the region. Kit Miyamoto of the non-profit Miyamoto Global Disaster Relief praised the community in Turkey that came together after the earthquake struck.

The community, the citizens are actually the first line of defense, he told CNN Wednesday. “They dug up family, friends, neighbors.”

The window for search-and- rescue is rapidly closing, warns another expert. Ilan Kelman is a professor of disasters and health at University College London, and he said that most survivors are pulled out after 72 hours.

He said time is the biggest enemy in Turkey and Syria. There are a number of reasons why people die, some of them due to immediate medical needs such as bleeding to death or succumbing to crush injuries and others due to earthquakes and the weather which has dropped below freezing at night and is cold during the day. Food and water are lacking for many who die waiting to be rescued.

The term “Richter Scale,” used by scientists for many years, has been replaced by the less accurate but still accurate “Modified Mercalle Intensity Scale” according to the US Geological Survey.

The power of an earthquake is known as magnitude. The intensity of the shaking can vary depending on the local geography and topography, and depth of the quake. On the magnitude scale, each increase of one whole number translates to 32 times more energy.

It is the strongest earthquake to hit in the world since an 8.1 magnitude earthquake hit near the South Sandwich Islands in the southern Atlantic Ocean in 2021, though the remote location caused little damage.

CNN has a severe weather expert who talks about the Epi-line but never the epicenter.

Source: https://www.cnn.com/2023/02/07/middleeast/earthquake-turkey-syria-why-deadly-intl/index.html

An Indonesian earthquake attorney is facing charges for his use of the word “where is the state” in a rant about the Turkish government’s response to the earthquake

In a strike slip the plates are moved horizontally rather than vertically. “Why that matters is because the buildings don’t want to go back and forth. The secondary waves start to go back and forth as well.

The coast of Indonesia was struck by an earthquake with an estimated magnitude of 9.1 in 2004, which caused a wave that left hundreds of thousands of people dead or missing.

The country had its worst nuclear disaster on record, as walls of water engulfed entire towns and dragged houses onto highways in the aftermath of that incident.

A verdant olive grove was cleaved into two during last week’s devastating earthquake in Turkey, creating a valley 984 feet long (about 300 meters) that now divides the area.

Irfan Aksu, who lives in the neighborhood, told Turkish news agency Demioren News Agency that when the earthquake started last Monday it created “an incredible sound” where he lived.

He asked experts to check the area for future damage. “This is not a small town, there are 1000 houses, and 7000 thousand people live here,” he said. “Of course, we are scared… if it was a little closer, it would have happened in the middle of our town.”

President Recep Tayyip Erdogan has long spoken of the need to be ready for natural disasters. A year after an earthquake hit Izmir and surrounding areas in 2020, Erdogan reportedly boasted that the government had been with the people “from the very first minute.”

Turkish prosecutors are looking into a lawyer for his use of the word “Where is the state?” in a rant about the government’s response to the earthquake. The lawyer was charged with a crime.

Building Safety in the Era of the 1999 Aegean Earthquake: Can the Government Survive? Comment on Turkish Prime Minister Sinan Ulgen

He said that the Turkey earthquake was a tragedy. Yet McCloskey is hopeful that we will learn from it. The next red line on a map will have no bearing on the catastrophic loss of lives if we do.

Ozgenler’s answer is yes. Improvements put on the books after the 1999 Aegean earthquake were a good start, but many more needs to be done.

Critics have pointed to so-called “zoning amnesties” given to contractors. These provided a way for buildings to be constructed more quickly, in part by skipping safety measures meant to strengthen a building’s capacity to resist an earthquake.

He says many of the buildings that toppled over this month were left with their upper stories basically intact. The ground floors are often used for commercial properties.

He says many businesses knocked out load-bearing walls or columns to increase their commercial space, which negatively impacted the structural integrity of the building.

“They have blood on their hands, and that makes me really, really angry when I see this,” Ozgenler says. “I mean, you don’t need an earthquake of 7.7 [magnitude] to see a building … fall over like this, if there’s no walls in the building, no core.”

Even if building owners or tenants do bear some blame for weakening buildings in earthquake-prone areas, analyst Sinan Ulgen at Istanbul’s Center for Economics and Foreign Policy says ultimately it’s up to the state to regulate that — to enforce the building codes on the books.

Ulgen says there will undoubtedly be a backlash of some kind against the government’s initial quake response, which may be why Erdogan has already pledged to provide shelter for all of the estimated 20 million people affected by the quake who need housing within a year.

This is all happening just weeks before elections were expected to be called, possibly to be held in May. The challenges of holding a vote in the earthquake hit areas still remain, and it’s not clear whether elections will be possible.

Ulgen says that the disaster will be a handicap for the government, because there is no polls showing the political impact of the disaster.

Source: https://www.npr.org/2023/02/20/1157837625/turkey-earthquake-damage-istanbul-safety-readiness

Aftershocks and rescue operations in the wake of the 2005 earthquake in Hatay, Turkey, said Interior Minister Süleyman Soylu

Noting that the elections are a constitutional obligation, he says ultimately it will be up to President Erdogan to decide if he wants to delay the vote, but doing so would require parliamentary approval that would need opposition support, which he sees as highly unlikely.

Adding to the uncertainty is the fact that the opposition coalition has yet to announce its own presidential candidate.

The quake’s epicenter was in the province’s Defne district, Turkish Interior Minister Süleyman Soylu said Monday, adding that there have been 26 aftershocks since.

In northwest Syria, there have been more than 130 injuries, the White Helmets volunteer rescue group said Monday. The quake also led to the collapse of a number of buildings that were already hit by the previous earthquake.

The White Helmets said they are working to take the injured to hospitals, inspect the affected villages and towns and open the roads for the ambulances.

The USGS initially reported the earthquake as being of magnitude 6 at a depth of 10 kilometers before changing it to magnitude 6.3.

The public have been told not to go to buildings. Turkish Vice President Fuat Oktay earlier Monday asked the public “not to enter the damaged buildings, especially to take their belongings.”

“We went back to our house and this shock happened again and we went out… may God help us,” said Zahir, who lives in a town between the cities of Iskenderun and Antakia, in Turkey’s Hatay province.

On Sunday, Turkey’s disaster management authority said it had ended most search and rescue operations nearly two weeks after the earthquake struck as experts say the chances of survival for people trapped in the rubble this far into the disaster are unlikely.

Early Warnings for California Earthquakes: Why February’s quake aftermath can be hard to predict and devastating for many people, not just in California

Earthquake forecasting could help in other regions as well. California, for example, which is home to the massive San Andreas fault, has implemented the beginnings of an early-warning system that relies on networks of seismometers to detect the very start of a quake. That can provide seconds or minutes of advance notice to Californians to ‘drop, cover and hold on’ while automatically triggering life-saving measures such as slowing trains to a stop.

It isn’t possible to use the technique everywhere. This model requires some knowledge of previous earthquakes and can only be used to assess areas where the history of earthquakes is well known. In the case of aftershocks, they are typically smaller than main shocks. Scientists are working hard to evaluate the model, and there are many unknowns.

That makes February’s aftermath particularly painful for those researchers who have been sounding the alarm for years. McCloskey says many people will be killed and their houses destroyed if a red line is put on a map.