It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
The Mendocino Triple Junction is the meeting point of three tectonic plates. Using data from tiny earthquakes, researchers at USGS, UC Davis and CU Boulder propose a new model for this seismic zone. The Pacific plate is dragging the Pioneer fragment under the North American plate as it moves north. At the same time, a fragment of the North American plate has broken off and is being subducted with the Gorda plate.
By tracking swarms of very small earthquakes, seismologists are getting a new picture of the complex region where the San Andreas fault meets the Cascadia subduction zone, an area that could give rise to devastating major earthquakes. The work, by researchers at the U.S. Geological Survey, the University of California, Davis and the University of Colorado Boulder, is published Jan. 15 in Science.
“If we don’t understand the underlying tectonic processes, it’s hard to predict the seismic hazard,” said coauthor Amanda Thomas, professor of earth and planetary sciences at UC Davis.
Three of the great tectonic plates that make up the Earth’s crust meet at the Mendocino Triple Junction, off the Humboldt County coast. South of the junction, the Pacific plate is moving roughly northwest against the North American plate, forming the San Andreas fault. To the north, the Gorda (or Juan de Fuca) plate is moving northeast to dive under the North American plate and disappear into the Earth’s mantle, a process called subduction.
But whatever is going on at the Mendocino Triple Junction is clearly a lot more complex than three lines on a map. For example, a large (magnitude 7.2) earthquake in 1992 occurred at a much shallower depth than expected.
First author David Shelly of the USGS Geologic Hazards Center in Golden, Colo., compared it to studying an iceberg.
“You can see a bit at the surface, but you have to figure out what is the configuration underneath,” Shelly said.
Shelly, Thomas, Kathryn Materna at CU Boulder and Robert Skoumal at USGS’s Earthquake Science Center at Moffett Field, Calif., used a network of seismometers in the Pacific Northwest to measure very small, “low-frequency” earthquakes occurring where the plates rub against or over each other. These earthquakes are thousands of times less intense than any shaking we could feel at the surface.
They confirmed their model by looking at how the plates respond to tidal forces. The gravitational forces of the Sun and Moon pull on tectonic plates just as they do on the waters of the ocean. When tidal forces align with the direction in which a plate wants to move, you should see more small earthquakes, Thomas said.
Five moving pieces
The new model includes five moving pieces, not just three plates – and two of them are out of sight from the Earth’s surface.
At the southern end of the Cascadia subduction zone, a chunk has broken off the North American plate and is being pulled down with the Gorda plate as it sinks under North America, the team found.
South of the triple junction, the Pacific plate is dragging a blob of rock called the Pioneer fragment underneath the North American plate as it moves northwards. The fault boundary between the Pioneer fragment and the North American plate is essentially horizontal and not visible from the surface at all.
The Pioneer fragment was originally part of the Farallon plate, an ancient tectonic plate that once ran along the coast of California but is now mostly gone.
The new model explains the shallowness of the 1992 earthquake, because the subducting surface is shallower than previously thought, Materna said.
“It had been assumed that faults follow the leading edge of the subducting slab, but this example deviates from that,” Materna said. “The plate boundary seems not to be where we thought it was.”
The work was supported by a grant from the National Science Foundation.
The fault beneath Istanbul doesn’t behave the way scientists once thought.
New research from USC shows that variations in underground temperature and sediment thickness segment the Main Marmara Fault in ways that control where earthquakes start, how far they spread and where they stop — findings that could reshape risk assessments for one of the world’s most vulnerable megacities.
The study, published in Nature Communications Earth & Environment, focuses on the North Anatolian Fault beneath the Sea of Marmara that hasn’t produced a major earthquake since 1894. Using physics-based simulations that model more than 10,000 years of seismic activity, researchers found that the fault is unlikely to rupture in a single, catastrophic event. Instead, it will likely break in segments, with maximum earthquake magnitudes reaching about 7.3.
“Fault geometry tells us where earthquakes are possible, but rheology — how rocks deform under stress — tells us how they actually unfold,” said Sylvain Barbot, the study’s principal investigator and associate professor of Earth sciences at the USC Dornsife College of Letters, Arts and Sciences. “Variations in temperature and rock type along the Main Marmara Fault act as barriers that can stop ruptures or cause the fault to creep instead of breaking in a large earthquake.”
How scientists simulated thousands of years of earthquakes
The Main Marmara Fault is part of the North Anatolian Fault system, which has produced devastating earthquakes throughout Turkish history. While previous studies mapped the fault’s geometry and slip rates, researchers hadn’t fully understood why earthquakes stop where they do — a critical question for estimating maximum possible magnitudes.
The answer lies beneath the seafloor. In the central Sea of Marmara, thick sedimentary basins sit above the warmer crust, creating what the researchers call a strong rheological barrier. Frictional properties of sedimentary rocks under specific temperature and pressure conditions show that they deform slowly and stably at shallow depths rather than breaking suddenly. Meanwhile, elevated temperatures at greater depths weaken rocks in ways that prevent large ruptures from growing.
“The main takeaway is that temperature and sediment thickness fundamentally change how the fault behaves,” said Sezim E. Guvercin, a postdoctoral researcher at USC Dornsife and first author of the study. “These variations create zones that resist rupture, particularly beneath sedimentary basins in the central Sea of Marmara.”
To test this, the research team built a three-dimensional earthquake-cycle model combining realistic fault geometry, frictional properties of rocks and thermal structure based on regional heat-flow measurements. The simulations used Unicycle, an open-source code that can model thousands of years of seismic cycles.
Different segments, different earthquake patterns
When the model incorporated both sedimentary layers and temperature variations, it reproduced key features of the historical record, including the large 1766 and 1912 earthquakes. Over the simulated period, no earthquake exceeded magnitude 7.3.
Different parts of the fault showed distinct patterns. The western Ganos and Tekirdağ segments, which are cooler and geometrically simpler, produce more regular earthquakes — including magnitude 7.2 events recurring roughly every 150 years. The eastern segments, Kumburgaz and Princes’ Islands, generate smaller, more frequent earthquake doublets, typically between magnitude 6.2 and 6.8 roughly every 100 years and a magnitude 7.0 earthquake roughly every 500 years.
The models also predict shallow creep — slow, continuous slip that releases stress without breaking — in parts of the fault near the Central Basin. That behavior matches geodetic observations and clusters of small, repeating earthquakes recorded over the past two decades.
“Earthquakes tend to nucleate near bends in the fault, where stresses are highest,” Barbot said. “But whether a rupture keeps going or stops is largely controlled by rheology.”
Models that ignored sedimentary basins or thermal structure consistently overestimated earthquake sizes and missed behaviors such as creeping segments. Only by incorporating the physical complexity of underground geology did the simulations match observed patterns.
What this means for Istanbul
The findings don’t reduce Istanbul’s earthquake risk. Moderate to large earthquakes occurring closer to the city, or in rapid succession, could still cause catastrophic damage. Instead, the research provides a more accurate picture of how the fault actually behaves — information essential for building codes, emergency planning and infrastructure decisions.
“Our work shows that what’s underground — heat, rocks and structure — matters enormously for earthquake behavior,” Guvercin said. “Integrating these factors is essential for improving seismic hazard forecasts in regions like Istanbul.”
The locked segments of the Main Marmara Fault on both sides have now gone more than 100 years without a major rupture. If these segments follow the patterns observed in simulations, the region may experience major earthquakes in the coming decades. Understanding exactly how the fault will break when it does could help identify which parts of Istanbul face the greatest risk.
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The study is funded by the National Science Foundation under award number EAR-1848192.
For her groundbreaking work in creating the earthquake information “hub” of the Earthquake Hazards Program, of the U.S. Geological Survey, the Seismological Society of America honors Lisa Wald with the 2026 Frank Press Public Service Award.
Wald began work at the USGS in 1987 in Pasadena, California, as a geophysicist and outreach director before becoming science communications and web content manager at the National Earthquake Information Center in Golden, Colorado, in 2002. She retired from the USGS in 2024.
“In the United States, the U.S. Geological Survey makes a wealth of earthquake information available, both educational resources and real-time products, in a variety of forms and through a variety of channels—including internet, text, and email—serving everyone from the general public to seismologists to governments to the media. Today we take that kind of information access for granted,” said USGS research geophysicist Sarah Minson, who nominated Wald for the award.
Minson noted that Wald worked with various USGS earthquake offices to pull together all the disparate USGS earthquake information into a single internet location, creating or facilitating the creation of most of the subsequent content on the USGS Earthquake Hazards Program website.
Wald taught herself HTML in the 1990s to build earthquake.usgs.gov, ushering in the internet era for the Survey. She was a key architect of the Earthquake Notification Service (ENS), which today allows users to receive custom automated earthquake event alerts, PAGER notifications about earthquake damage and fatality estimates, aftershock forecasts and more.
In 2015, Wald helped to produce the first U.S. Federal Crowdsourcing and Citizen Science Tool Kit to aid federal agencies in carrying out citizen science and crowdsourcing projects. She was invited by the White House Office of Science and Technology Policy to be the web designer on the tool kit team.
During her time at USGS, Wald created a wide range of digital products for students, educators and the public, including Earthquakes for Kids, The Science of Earthquakes and the Science for Everyone series. Wald was also on the receiving end of all email inquiries sent to eq_questions@usgs.gov for almost two decades. She answered every one of what amounted to around 1000 emails every year. In their commendations of Wald, her colleagues noted her service in providing communications tutorials and advice for generations of scientists in and out of the federal government.
The Frank Press Public Service Award honors outstanding contributions to the advancement of public safety or public information relating to seismology. This award may be given to any individual, combination of individuals, or organization.
Thursday, January 08, 2026
Peruvian shamans’ first 2026 prediction comes true with Nicolás Maduro's fall
While Trump’s operation to capture Venezuelan President Nicolás Maduro shocked the world, it was foretold just days earlier in Peru...
Don’t bet against Peruvian shamans, it seems.
On 29 December 2025, a group of shamans gathered by the sea in the Miraflores district of Peru’s capital Lima for their annual ritual: forecasting what the coming year has in store for the world when it comes to global leaders, ongoing conflicts, and the course of international relations.
They meet to drink hallucinogenic concoctions derived from native plants - including Ayahuasca and the San Pedro cactus - which are believed to give them the power to predict the future.
And wouldn’t you know it, despite a mixed record with their annual predictions, one of their 2026 prophecies has already come true, as they foretold that Donald Trump would oust Venezuelan President Nicolás Maduro.
Shamans perform a personalized blessing for a man during their annual ritual - 29 December 2025 AP Photo
“We have asked for Maduro to leave, to retire, for President Donald Trump of the United States to be able to remove him, and we have visualized that next year this will happen,” said shaman Ana María Simeón, a full five days before Maduro was captured in a military operation that Donald Trump said would set the US up to "run" the South American country and tap its vast oil reserves.
The prediction was only partially accurate, however. While the group foresaw the fall of the 63-year-old Venezuelan leader, they believed he would flee and not be captured.
"We see Nicolas Maduro defeated," proclaimed another shaman, Juan de Dios Garcia. "Nicolas Maduro will flee Venezuela. He will not be captured."
Shamans hold a photo of Donald Trump during their annual ritual to predict political and social issues for the new year - 29 December 2025 AP Photo
Another one of the group’s predictions for this year also concerns Trump: "The United States should prepare itself because Donald Trump will fall seriously ill," Juan de Dios Garcia proclaimed.
Even if the shamans called for peace and healing worldwide, the 2026 outlook doesn’t look too rosy: they have predicted natural disasters, such as earthquakes, and while they foresee the end of Russia’s war in Ukraine, they previously made the prediction that the conflict would end in 2023.
Last year, they also warned a "nuclear war" would break out between Israel and Gaza, where a ceasefire is currently in place.
However, in December 2023, the group correctly predicted that former Peruvian President Alberto Fujimori, who had been imprisoned for human rights abuses, would die within twelve months. Fujimori died from cancer in September 2024 at the age of 86.
