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First-Ever Fault Rupture Captured On Video During Myanmar Earthquake
First-Ever Fault Rupture Captured On Video During Myanmar Earthquake

Forbes

time2 days ago

  • Science
  • Forbes

First-Ever Fault Rupture Captured On Video During Myanmar Earthquake

Video showing shaking of the surface and at 0:16 a sudden offset as part of the ground moves (for ... More the observer) from the left to the right. A video uploaded just a few days after a powerful earthquake hit Myanmar on March 28, 2025, quickly captured attention of the geological community, as it shows the exact moment the ground ruptures along a fault. The video comes from a CCTV security camera recording along the trace of Myanmar's Sagaing Fault, which ruptured in a magnitude 7.7 earthquake. The camera was placed about 20 meters to the east of the fault and was 120 kilometers away from the earthquake's center. When geophysicist Jesse Kearse and his colleague Yoshihiro Kaneko at Kyoto University analyzed the video more carefully, they noted that the video not only shows a fault in motion as never seen before — shaking followed by a visible slide of the ground — but reveled the dynamics of fault slip. 'I saw this on YouTube an hour or two after it was uploaded, and it sent chills down my spine straight away,' Kearse recalls. 'It shows something that I think every earthquake scientist has been desperate to see, and it was just right there, so very exciting.' Geological clues, like curved scrape marks on fault planes, already suggested that blocks of rock moving past each other during faulting rotate slightly , but until now there has been no visual proof for this geomechanical behavior. 'Instead of things moving straight across the video screen, they moved along a curved path that has a convexity downwards,' Kearse explains. The researchers decided to track the movement of objects in the video by pixel cross correlation, frame by frame. The analysis helped them measure the rate and direction of fault motion during the earthquake. They conclude that the fault slipped 2.5 meters for roughly 1.3 seconds, at a peak velocity of about 3.2 meters per second. This shows that the earthquake was pulse-like, which is a major discovery and confirms previous inferences made from seismic waveforms of other earthquakes. In addition, even if most of the fault motion is vertical (a classic strike-slip fault), the slip curves at first, then remains linear as the slip slows down. The pattern fits with what earthquake scientists had previously proposed, as the ground breaks first at the weakest point (in this case the surface) and then the rupturing fault follows. The video confirmation can help researchers create better dynamic models of how faults rupture and how the energy of an earthquake spreads from its point of origin, Kearse and Kaneko conclude. The full study, "Curved Fault Slip Captured by CCTV Video During the 2025 Mw 7.7 Myanmar Earthquake," was published in the journal The Seismic Record and can be found online here. Additional material and interviews provided by the Seismological Society of America.

First video of an earthquake fault cracking has revealed another surprise
First video of an earthquake fault cracking has revealed another surprise

Yahoo

time19-07-2025

  • Science
  • Yahoo

First video of an earthquake fault cracking has revealed another surprise

When you buy through links on our articles, Future and its syndication partners may earn a commission. A first-of-its-kind video showing the ground cracking during a major earthquake is even more remarkable than previously thought. It not only captures a ground motion never caught on video before but also shows the crack curving as it moves. This curvy movement has been inferred from the geological record and from "slickenlines" — scrape marks on the sides of faults — but it had never been seen in action, geophysicist Jesse Kearse, a postdoctoral researcher currently at Kyoto University in Japan, said in a statement. "Instead of things moving straight across the video screen, they moved along a curved path that has a convexity downwards, which instantly started bells ringing in my head," Kearse said, "because some of my previous research has been specifically on curvature of fault slip, but from the geological record." The video — captured by a security camera near Thazi, Myanmar — shows the ground rupturing during a magnitude 7.7 quake that hit the region on March 28. It shows the ground shaking, followed by a crack opening up. These ground ruptures are relatively common during big quakes, but they'd never been caught on video. Kearse said he watched the video with chills down his spine shortly after it was uploaded to YouTube. On his fifth or sixth viewing, he noticed that the crack was curvy. He and his colleague at Kyoto University, geophysicist Yoshihiro Kaneko, then analyzed the video more closely. They found that the crack curves sharply at first and then accelerates to a peak velocity of about 10.5 feet per second (3.2 meters per second) of movement, slipping a total of 8.2 feet (2.5 meters) in 1.3 seconds. After hitting its top velocity, the crack straightens and slows. The findings suggest that the curvature happens because stresses on the fault right at the ground surface are lower than the stresses on the fault deeper in the Earth. This creates an uneven pattern in how the fault moves. "The curvature holds important information about the dynamics of the rupture," Kearse said in an annotated video of the slip he posted on YouTube. Related: The San Andreas Fault: Facts about the crack in California's crust that could unleash the 'Big One' The differing stresses at the surface push the fault off its course, "and then it catches itself and does what it's supposed to do," Kearse said in the statement. RELATED STORIES —'This is a very big earthquake': The science behind Myanmar's magnitude 7.7 earthquake —20 largest earthquakes in history —Scientists find hidden mechanism that could explain how earthquakes 'ignite' The dynamics of these curvatures depend in part on which way the rupture travels, so an understanding of the curves can reveal clues about how past earthquakes unfolded and help scientists better predict future ground ruptures. The research was published today (July 18) in the journal The Seismic Record. Editor's Note: This article was updated at 8:20 p.m. EDT to note that the new research has now been published in The Seismic Record.

Scientists sound alarm over massive underwater force threatening to accelerate city collapse: 'Potentially double or triple the effects'
Scientists sound alarm over massive underwater force threatening to accelerate city collapse: 'Potentially double or triple the effects'

Yahoo

time11-05-2025

  • Science
  • Yahoo

Scientists sound alarm over massive underwater force threatening to accelerate city collapse: 'Potentially double or triple the effects'

Rising sea levels and subsiding shorelines are putting New Zealand's coastal communities at risk. A new study revealed that human activities heighten and expedite the risks of sinking cities. As Forbes reported, a group of New Zealand researchers studied how the island's cities and shorelines are sinking. This is concerning because sinking cities may be affected by rising sea levels sooner than previously anticipated. In New Zealand and globally, sea levels are rising due to our warming climate and melting ice in polar regions. Meanwhile, localized instances of human activity, such as groundwater extraction, land reclamation, and dredging, are causing coastal lands to sink. Kyoto University researcher Jesse Kearse said these activities can "potentially double or triple the effects of sea-level rise in certain places." The researchers determined that coastal infrastructure is at risk because of this sinking effect and rising sea levels. In their study, they used satellite-based mapping and radar images to assess the physical properties of surfaces and measure ground deformation. Focusing on vertical land movement at urban coastal strips between 2018 and 2021, they observed coastal strips decreasing in all of New Zealand's major population centers. Some areas are experiencing subsidence rates of over 15 millimeters per year. This revelation is significant because billions of people live near coastlines. No coastal city, in New Zealand or elsewhere, is immune to rising sea levels. With supercharged weather events becoming more common as our climate warms, people living along the coast face considerable danger. This study also stands out because it highlights humans' impacts on at-risk coastlines. The researchers noted that areas of reclaimed land in New Zealand are particularly vulnerable to the land's stability. What would you do if natural disasters were threatening your home? Move somewhere else Reinforce my home Nothing This is happening already Click your choice to see results and speak your mind. Land reclamation involves filling water-submerged areas with soil, rock, or other materials to create new land where water once flowed. The researchers concluded by pointing out many unanswered questions regarding subsidence rates and how long they will persist. They also warned about the risks of future development in coastal areas due to vertical land motion patterns. Research studies like this one raise public awareness about coastal community risks and the threats of rising sea levels, especially when extreme storms hit. Fortunately, governments and businesses are working on technologies to adapt and plan ahead. For example, innovators use predictive artificial intelligence and smart reefs to protect residents from floods. Architecture firms have designed floating homes as practical solutions for people living in flood-prone areas. Meanwhile, officials have developed plans to protect coastal lands by planting mangroves and adding sand piles. If you live along the coast, there are steps you can take to protect yourself and your home. Preparing for hurricanes and floods is crucial, so keep a go bag packed if you need to evacuate. To prepare for future power outages, you can install solar panels or sign up for a community solar program. (Solar is also a type of clean energy. In other words, the photovoltaic panels don't generate any troublesome heat-trapping pollution when turning sunlight into power.) Hurricane-proofing your house by raising it and installing a custom seawall can help as well as reinforcing your home with durable materials to boost its resilience and give you peace of mind. Join our free newsletter for good news and useful tips, and don't miss this cool list of easy ways to help yourself while helping the planet.

New Zealand's Major Cities Are Sinking
New Zealand's Major Cities Are Sinking

Forbes

time16-04-2025

  • Science
  • Forbes

New Zealand's Major Cities Are Sinking

Global mean sea level has risen about 21-24 centimeters (8-9 inches) since 1880. Staggeringly, somewhere around 10 cm of that rise has happened in the past 30 years, and the rate at which sea levels are rising is accelerating – it was ~2.1 mm/year in 1993, and now it's ~4.5 mm/year. For coastal populations, of which there are a lot – close to 1 billion people (or ~12.5% of the world's population) live within 10 km of a coastline – sea level rise isn't some far off threat. Its impacts are already being felt. Storm surges during Hurricane Helene brought devastation to coastal communities across the Southeast US in 2024. Cities including NYC, and Panjin in China are increasingly experiencing floods at high tide, even in times of good weather. No coastal city is immune to the impacts of sea-level rise. And as a new study from a group of New Zealand researchers shows, human activity is exacerbating the risk. Their analysis found that in many NZ cities, shorelines are steadily subsiding or sinking, which means that rising seas will affect them sooner. Global sea level rise is largely driven by two factors, that in turn are a result of our warming climate. The first (and largest) contributor is the melting of ice sheets and glaciers, particularly in the polar regions. The Greenland ice sheet alone is estimated to be shedding about 270 billion tons of ice per year. The second driver is the thermal expansion of the ocean. Water, like all liquids, expand when they're heated. And more than 90% of the heat trapped in our atmosphere – thanks to an accumulation of greenhouse gases – is eventually absorbed by our oceans. A warmer ocean takes up more space than a cooler one, and so we're seeing higher sea levels. This effect is estimated to cause roughly one-third of the global sea-level rise observed by satellites since 2004. However, there are other causes that are far more localized. The land itself may be sinking (or lifting), either as a result of tectonic activity, or of human activity – namely, groundwater extraction, dredging, and land reclamation. These activities can 'potentially double or triple the effects of sea-level rise in certain places,' writes Dr Jesse Kearse, a Postdoctoral Researcher at Kyoto University. Here in Aotearoa NZ, the effects of these land changes on urban areas have been examined in detail for the first time. The results paint a rather worrying picture for our coastal infrastructure. Kearse is the lead author of this new paper, and an expert on measuring vertical land motion using a satellite-based mapping technique called InSAR (Interferometric Synthetic Aperture Radar). 'InSAR allows us to map ground deformation using radar images of the earth's surface,' he explains, speaking over Zoom from Japan. 'It's an active source imaging system – it's not about passively collecting reflected light like you do for optical images. The radar signal is beamed down from a satellite, it hits the surface and reflects back.' The radar satellite used by Kearse and his colleagues is called Sentinel-1. For the past decade, it has been continuously collecting radar imagery of our planet, and making it available via the European Space Agency's database. It's been used to monitor everything from marine winds to soil moisture, and for emergency responses. Unlike optical satellites, SAR can see through clouds and operate both day and night. Captured within a radar image are two pieces of information: amplitude and phase. You can think of the amplitude as the strength of the return signal – it is influenced by the physical properties of the surface. But if you're interested in measuring ground deformation, phase is the useful part. Radar waves have a specific wavelength, 'around five centimeters' in the case of Sentinel-1, so the distance from the satellite to the ground and back again can be expressed in terms of that wavelength (distance = some number of full wavelengths plus some fraction of a wavelength). When you compare two images of the same area taken on different dates, anywhere that you find extra or fewer fractions of a wavelength (i.e. a change in phase) will likely be a spot where the ground has changed its vertical position between those images – it may have subsided or lifted, relative to the ground around it. Phase differences can be measured with very high accuracy. To turn those relative measurements of vertical motion into true or absolute measurements, you need to use a reference – ideally sensors on the ground within the same area that can also measure small ground movements. New Zealand already has a network of suitable sensors. Called GeoNet, it acts as a geological hazard monitoring system, and it continuously collects ground deformation data from its GNSS stations around the country. The combination of high-resolution InSAR data and GeoNet's GNSS data allowed Kearse and his colleagues to measure vertical land movement between 2018 and 2021 at major urban coastal strips around the country; namely, Auckland, Tauranga, Wellington, Christchurch, and Dunedin. Together, these areas are home to the majority of the population. 'One of our main conclusions was that the coastal strip is going down consistently in all of these cities, and it's happening at a rate of a few millimeters each year,' Kearse says. In terms of numbers, they found that 77% of NZ's urban coastlines are subsiding at rates of 0.5 mm/yr or more. Some of the fastest subsidence rates – more than 3.0 mm/yr – were measured in the coastal suburbs of Christchurch. They also identified highly-localized hotspots, with subsidence rates exceeding 15 mm/yr in some cases. 'These human-modified parts of the coastline are going down at locally much faster rates than the rest of the coast, which in turn is going down faster than the inland areas,' he says. While the researchers didn't delve into the cause of these subsidence hotspots in this paper, Kearse has noticed a pattern. 'There's a lot of reclaimed land in New Zealand cities – some of it you cannot detect, and some stands out really clearly in the images. I'm not an engineer, but the methodology or the engineering approach that was used to reclaim the land seems to have a significant effect on its current stability.' In the interview, he gives the example of Wellington Airport whose construction required the movement of 'three million cubic meters of earth and rock', as well as significant land reclamation. 'That was a huge engineering effort. A lot of research, a lot of care and attention was paid to that construction,' says Kearse, 'and it remains very stable. But then you have areas like Naval Point [in Christchurch] Many of the subsiding areas are home to heavy industries, ports and other critical infrastructure like wastewater treatment plants. When asked how worried the public should be about this in the coming decades, Kearse says, 'I think that's a bit outside of my expertise, but my personal opinion is that there are still a lot of unanswered questions in terms of what's actually going on. Are these subsidence rates going to persist for decades to centuries? It's not clear.' Something that complicates the picture is the fact that New Zealand is one of the most seismically-active areas on the planet. It straddles the boundary of two tectonic plates – the Pacific plate and the Australian plate. At the bottom of the South Island (Te Waipounamu), the Australian Plate dives, or subducts, below the Pacific plate. Just off the east coast of the North Island (Te Ika-a-Māui), the situation is reversed – there, the Pacific plate plunges below the Australian one. Wellington's location along the plate boundary means that it can experience large, sudden quakes as well as 'slow-slip events', where faults can move over a period of weeks or months. This complexity is 'really problematic for trying to understand long-term vertical land motion in the capital city,' says Kearse 'In inter-slow-slip time periods, the whole subduction system pulls Wellington down by about 3 mm a year. And then for a few months that will rebound and it might regain 50 or 60% of that accumulated subsidence. And then the cycle will repeat again.' Kearse says that he found no evidence of land subsidence accelerating in recent years – 'in most cases, it was either pretty steady or even decelerating' – but he reemphasized the paper's conclusions, saying 'Vertical land motion has to be considered in any assessment of sea level rise, and in any future development plans for those vulnerable urban areas.'

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