Latest news with #seismicwaves
Daily Mail
17-07-2025
- Science
- Daily Mail
Monster Alaska earthquake rocks state and sparks tsunami...and scientists warn it may not be over
A powerful 7.3-magnitude earthquake struck the Alaska on Wednesday, sending seismic shockwaves racing through the Earth's crust and lighting up The quake, which hit at 12:38pm local time (4:30pm ET), triggered an immediate tsunami warning for parts of coastal Alaska and rattled a vast swath of the Pacific Rim. But scientists now warn the true danger may just be beginning. Although the shaking was felt most intensely in southern Alaska, where it struck near the Aleutian subduction zone, the energy released by the quake did not stay local. Seismic waves, vibrations that travel through the Earth, activated seismic sensors as far east as the East Coast of the US and reaching across the ocean to Europe and parts of Asia and Africa. While the vibrations were not strong enough to be felt by people thousands of miles away, sensitive instruments captured every pulse of the Earth's movement in real time. Using a global network of sensors and cutting-edge computer simulations, scientists converted the raw data into animations showing how the seismic energy rippled out from the epicenter like waves from a stone thrown into water. A yellow star marked ground zero on the map in Alaska, while red and blue dots representing seismic stations lit up one by one as the waves swept past. In less than a minute, the tremors had reached monitoring stations across the world. Large earthquakes are known to redistribute stress along fault lines, sometimes increasing the strain on already vulnerable zones. If those areas are near their breaking point, the added pressure could trigger aftershocks or even fresh quakes, not just locally, but potentially in distant regions connected by geological stress transfer. In rare cases, shifting stress can also activate entirely separate fault systems, making this kind of global disturbance more than a geological curiosity. This happened in 1992, when a major 7.3 magnitude earthquake hit California and within hours, of the mainshock, seismic activity increased in places of the mainshock, seismic activity increased in places up to 750 miles away, including in Yellowstone National Park and western Nevada. When an 8.8 magnitude quake rocked Chile in 2010, the seismic waves triggered activity in Mexico and Southern California. The vibrations were captured using real-time computer simulations that convert raw seismic data into animations of Earth's movement, showing how ground motion travels outward from the epicenter. An animation of the traveling shockwaves depicted blue and red seismic stations scattered across the map, lighting up as each recorded the powerful geological event. The visual sequence, starting at 0.00 seconds, showed the epicenter marked with a yellow star, with a red line tracing the expanding wavefronts as they moved away from Alaska. As time progressed from 1.97 to 64.94 seconds, the seismic waves continued their relentless expansion. In the early stages, between 1.97 and 15.74 seconds, the waves primarily impacted the western coast of North America. The primary waves reached seismic stations in Alaska and the Pacific Northwest, with the red line on the map illustrating their rapid advance. This phase highlighted the immediate regional impact, where the energy of the quake was most intensely concentrated. During the mid-stages, from 17.71 to 37.39 seconds, the seismic waves pushed further inland across the US. The wavefronts began to reach stations in Canada and the central US, demonstrating the broadening scope of the earthquake's influence. The red line on the map continued to extend, tracking the waves' progression as they traversed the continent. In the later stages of the event, between 39.36 and 64.94 seconds, the seismic waves reached the East Coast and began influencing stations in Europe and Asia. Adding to the mystery, a massive magnetic pulse was detected at the exact moment the earthquake occurred. The very second the rupture began, Earth's magnetic field showed a sharp spike. Within hours, a G1-class geomagnetic storm developed, disrupting the planet's magnetic environment. Strangely, this occurred despite otherwise nominal solar wind conditions, prompting researchers to question whether the quake may have played a role in triggering the storm. While the link between earthquakes and geomagnetic activity remains poorly understood, the coincidence is striking.
Yahoo
25-06-2025
- Science
- Yahoo
Something Strange Is Happening 1,700 Miles Beneath Your Feet. Now We Know Why.
"Hearst Magazines and Yahoo may earn commission or revenue on some items through these links." Here's what you'll learn when you read this story: Over a thousand miles from the surface, in Earth's D' layer—right on the edge of the liquid metal outer core—there is a weird acceleration of seismic waves. Experiments recreating the phenomenon in a lab found that this is the result of post-perovskite crystals, which form from perovskite. The alignment of these crystals determines their hardness, which then determines how fast seismic waves can move through them. Deep beneath Earth's surface are layers of soil, rock strata often embedded with fossils, gurgling magma, and—back up. Before your Journey to the Center of the Earth mission can get any further, you're going to have to get past flows of solid rock. The D' layer—located between layers of magma above and the liquid rock of the outer core below—has been mystifying scientists for decades. This is in part because if you were to plunge down 2,700 kilometers (1,700 miles), you would be jump-scared by seismic waves that accelerate when they hit the threshold of the D' layer. It used to be thought the reason for this was the mineral perovskite, found in the lower mantle, morphing into a form known as post-perovskite close to the D' layer. But that still wasn't enough to explain the phenomenon. Geoscientist Motohiko Murakami wanted to investigate what could possibly be going on to cause the strange seismic wave acceleration known as the D' discontinuity. Because trekking to the core-mantle boundary (CMB) where the D' layer lies is obviously not an option, he led a team of researchers from Switzerland and Japan in running lab tests and computer simulations to find out what post-perovskite had to do with he unusual increase in seismic waves. Post-perovskite crystals are anisotropic, meaning their physical properties are different when measured in different directions. They have two different types of textures—one comes from transformation (the phase transition from the perovskite phase to post-perovskite), and the other is a result of deformation (when post-perovskite crystals turn to face in the same direction). Murakami and his team found out that it isn't just transformation that causes the rumbling. It actually happens with deformation. 'The deformation-induced texture forms when crystals undergo plastic deformation, causing their orientations to align in specific directions. It is mainly produced by dislocation slip or creep,' Murakami said in a study recently published in the journal Communications Earth & Environment. How post-perovskite crystals are aligned determines their hardness, and the speed at which seismic waves move through them depends on how hard they are. Materials called perovskites can be created from any substances capable of being arranged into the same cubic crystal structure. Perovskite is a calcium titanium oxide mineral (CaTiO3), while post-perovskite is a form of magnesium silicate (MgSiO3) achieved at extremely high pressures. Its crystal structure is orthorhombic, meaning that the right angles of the cubes have unequal axes. For post-perovskite crystals to align with each other, the axes all have to be in the same position. Murakami used MgGeO3 to create crystals analogous to post-perovskite. Like perovskite, MgGeO3 crystals deform easily when pressure is applied, so how they behaved would reflect was is going on over a thousand miles underground. The crystals were heated by a laser, compressed, and heated again to synthesize post-perovskite. They were then exposed to high-pressure sound waves, and the wave velocity was measured once those waves passed through the crystals. It turned out that sound waves can experience a substantial increase in velocity when passing through aligned post-perovskite crystals. Researchers also discovered that the cause of this alignment—which determines the hardness of the material, and therefore the speed of sound waves in the lab and seismic waves deep in Earth—is convection. As hotter material rises, cooler material sinks, as it does in convective storms like hurricanes. Murakami thinks that convection of materials in the mantle (such as plumes rising and slavs sinking) is behind the deformation in the D' layer. This is the first time any evidence—even lab-based evidence—has been found for Earth's innards moving. 'While previous theoretical work has suggested that anisotropy could explain the observed seismic discontinuities,' he said. 'Our results, obtained through in situ measurements of post-perovskite velocities under high pressure, represent the experimental verification of this hypothesis, bridging the gap between theory and observation.' You Might Also Like The Do's and Don'ts of Using Painter's Tape The Best Portable BBQ Grills for Cooking Anywhere Can a Smart Watch Prolong Your Life?
Yahoo
17-06-2025
- Science
- Yahoo
Solid Rock Caught Flowing 1,700 Miles Beneath Surface in Experimental First
The D" layer, some 2,700 kilometers (nearly 1,700 miles) below our feet, has been mystifying scientists for decades. Now we may have an answer as to what exactly goes on in this special zone deep inside Earth – solid rock is flowing. Seismic waves unexpectedly speed up as they pass through the boundary of the D" layer, and a 2004 study seemed to find the answer: it showed that extreme pressures and extreme temperatures could turn the lower mantle mineral perovskite into a different form labeled 'post-perovskite', somewhere around the D" layer boundary. However, it was later found that this new phase isn't enough on its own to explain the acceleration of seismic waves. For the new study, scientists in Switzerland and Japan ran computer simulations and lab tests to determine that the crystals in post-perovskite all need to be pointing in the same direction for seismic waves to speed up. "This discovery not only solves the mystery of the D" layer but also opens a window into the dynamics in the depths of the Earth," says geoscientist Motohiko Murakami, from ETH Zurich in Switzerland. "We have finally found the last piece of the puzzle." The researchers essentially recreated the deep layers of Earth in their lab, on a much smaller scale. They found that the alignment of the post-perovskite crystals determines its hardness, and thus the movement of waves rippling through it. They found something else, too: that the solid rock above the D" layer can flow in a convection pattern. This type of movement, which varies across different parts of Earth's layers, determines the alignment of post-perovskite crystals. It's driven by a combination of cooler material, which is sinking, and hotter material, which is rising. It's the first experimental evidence we have of such movement in this region of Earth's insides – though of course direct observations are impossible. "These findings indicate that the texture of the post-perovskite phase can explain most of the key features of the D" discontinuity," write the researchers in their published paper. This all feeds into our knowledge of the complex interplay of heat, pressure, and movement that's happening way down deep under Earth's surface. Having a better understanding of these forces then tells us more about everything from volcanic eruptions to Earth's magnetic field. The core-mantle boundary (CMB), which is where the solid mantle hits Earth's liquid outer core, is of particular interest to scientists. It represents a huge switch between materials in terms of density, composition, conductivity, and other measures – making it vital to the most fundamental forces driving our planet. "Our discovery shows that the Earth is not only active on the surface, but is also in motion deep inside," says Murakami. While the study helps answer some questions, there are still a lot of mysteries left down there. The research has been published in Communications Earth & Environment. Hundreds of Mysterious Giant Viruses Discovered Lurking in The Ocean Scientists Just Solved a 100-Million-Year-Old Mystery About Platypus Sex Deep-Sea Wonderland Found Thriving Where Humans Have Never Been
Sustainability Times
17-05-2025
- Science
- Sustainability Times
'Sea Storms Rattle the Core': Shocking New Study Reveals Ocean Waves Penetrate Deep Into Earth's Interior Layers
IN A NUTSHELL 🌊 Ocean storms in the North Atlantic generate microseisms that travel through the Earth's core, providing new insights into its structure. in the North Atlantic generate microseisms that travel through the Earth's core, providing new insights into its structure. 🔍 Researchers used spiral-shaped seismometers in Australia to detect PKP waves, a rare type of seismic wave caused by cyclones. in Australia to detect PKP waves, a rare type of seismic wave caused by cyclones. 🌌 This method could revolutionize planetary exploration by offering a way to study the interiors of planets and moons without tectonic activity. by offering a way to study the interiors of planets and moons without tectonic activity. ⚙️ Challenges include the faintness of storm-generated signals and the need for advanced equipment and precise data processing techniques. In a groundbreaking study, scientists have discovered that ocean storms can provide valuable insights into the Earth's interior. Traditionally, researchers relied on earthquakes to study the Earth's core, but this method has proven unreliable. Now, ocean storms, particularly those in the North Atlantic, are offering a more consistent and revealing alternative. As these storms unleash chaos on the ocean's surface, they send shockwaves deep into the Earth, traveling through its liquid outer core and solid inner core. This innovative approach not only enhances our understanding of Earth's structure but also opens new possibilities for exploring other planets. Catching the Sound of the Ocean When massive storms rage across the North Atlantic, they generate powerful ocean waves that clash, producing tiny vibrations known as microseisms. Unlike vibrations caused by tectonic activity, these microseisms result from storm waves colliding. While their energy is much weaker than that of earthquakes, some of these vibrations can travel thousands of miles through the Earth's core. Previously dismissed as mere background noise, microseisms have now emerged as a treasure trove of data, thanks to advanced equipment and sophisticated processing techniques. To capture these subtle vibrations, researchers from the Australian National University (ANU) deployed two arrays of spiral-shaped seismometers in remote areas of Queensland and Western Australia. These instruments were specifically designed to detect PKP waves, a rare type of seismic wave generated by cyclones that travel through Earth's core. During Australia's summer months, the team successfully recorded signals produced by winter storms in the far northern Atlantic. Although the strength of these microseisms was only a fraction of that produced by earthquakes, their frequent and uniform occurrence made them ideal for studying the Earth's inner layers. 'Concrete That Heals Itself': Scientists Create Lichen-Inspired Material That Uses Microbes to Seal Cracks Automatically What It Means for Earth and Beyond While Earth is known for its tectonic activity, many other planetary bodies lack such frequent geological events. However, they do have atmospheres and storms, which could generate similar microseisms. By detecting these vibrations, scientists could gain insights into the interiors of planets without relying on earthquakes. This technique, however, presents certain challenges. The faint storm-generated signals can be easily masked by local noise, and their detection depends on factors such as seafloor topography, ocean depth, and storm characteristics. As a result, not all locations on Earth or other planets are equally suitable for this approach. According to Hrvoje Tkalčić, a co-author of the study and professor at ANU, the signals are complex and vary based on the source and receiver path. Efficient methods and modern observational infrastructure, such as ocean bottom seismometer pools, are essential for detecting and recording these signals. Future research will focus on refining equipment and studying how seismic waves change as they pass through different parts of Earth's core. The findings of this study have been published in the journal Seismological Research Letters. Lead Transformed into Gold: CERN Scientists Stun World with Historic Alchemy Breakthrough After Decades of Failed Experiments The Implications for Planetary Exploration The discovery that ocean storms can reveal information about the Earth's interior has significant implications for planetary exploration. As scientists seek to understand the composition and structure of other planets, this method offers a promising alternative to traditional seismic techniques. By detecting microseisms generated by storms on other planets, researchers can gather data about their internal structures without relying on tectonic activity, which may be absent. This approach is particularly valuable for exploring icy moons and other celestial bodies where earthquakes are unlikely to occur. Abhay Pandey, a PhD student at ANU and study co-author, emphasizes that this method could be instrumental in identifying planets with cores, even those lacking plate tectonics or volcanic activity. By leveraging weather-driven vibrations, scientists can gain a deeper understanding of our solar system and beyond, paving the way for future exploration missions. This Colossal Chinese Telescope Just Turned to the Moon: Hunt for Buried Lunar Water Enters Unstoppable New Phase Challenges and Future Directions Despite the exciting potential of using ocean storms to study planetary interiors, several challenges remain. The faintness of storm-generated signals requires advanced equipment and precise data processing techniques. The detection of these signals is influenced by various factors, including the seafloor's shape, ocean depth, and storm intensity. As such, researchers must carefully select study locations to maximize the effectiveness of this approach. Moving forward, scientists will continue to refine their equipment and methods to enhance the detection and analysis of microseisms. By improving our understanding of how these vibrations interact with Earth's core, researchers can unlock new insights into our planet's structure. Additionally, as we venture into space exploration, this method could become a valuable tool for studying the interiors of other planets and moons. How will this innovative approach shape our understanding of the universe and our place within it? Our author used artificial intelligence to enhance this article. Did you like it? 4.4/5 (24)
