Yellowstone Is Hiding Something Much Bigger Than Scientists Have Predicted

California. California. California. California. California. When we have another big earthquake, it's going to be tens of billions of dollars and hundreds if not thousands of lives lost. Something beneath California has been moving. In early 2025, NASA satellites revealed California actively shifting, with parts of the Central Valley sinking eight inches annually. By 2026, the Long Valley Caldera dropped over two inches. These aren't measurements reconstructed only from ancient rocks. They're changes detected during the last few years. Today on DiscoverTube, we're following 20 of them across California. From moving faults and collapsing aquifers to landslides, magma, volcanic systems, and a major tectonic boundary hidden beneath the Pacific. 1. The 2025 NASA Study That Found California Moving On February 10, 2025, NASA's Jet Propulsion Laboratory released results from a study that gave researchers a remarkably detailed view of California's moving surface. The team analyzed satellite observations collected between 2015 and 2023. The measurements came partly from the European Space Agency's Sentinel-1 satellites. Researchers used a technique called Interferometric Synthetic Aperture Radar, or INSAR. Instead of simply photographing California, radar observations taken at different times can be compared to detect extremely small changes in the position of the ground. And the resulting map wasn't uniform. California was moving differently depending on where researchers looked. Around San Rafael, Corta Madera, Foster City, and Bay Farm Island in the San Francisco Bay Area, researchers measured subsidence exceeding approximately 10 millimeters per year. But farther inland, the numbers became much larger. In fast-sinking parts of California's Central Valley, the study identified subsidence reaching approximately 20 centimeters per year. That's almost 8 inches annually. The researchers also found the opposite. Parts of the Santa Barbara groundwater basin were rising by several millimeters per year as groundwater replenished the aquifer. The study's lead author, NASA JPL remote sensing scientist Marin Gavorson, explained that land movement can sometimes contribute substantially to local sea level effects. So this isn't simply a story about California's geological past. NASA and NOAA researchers used measurements extending through 2023, published the results in 2025, and showed that California's surface is still moving now. But vertical movement is only one part of the state. Another system moves California sideways. 2. The 800-Mile Fault That Never Stopped Moving The San Andreas Fault stretches nearly 800 miles across California. It marks a major portion of the boundary between the Pacific and North American tectonic plates. Those plates don't collide head-on here. They slide horizontally past each other. Most of the time, that movement happens slowly enough that nobody standing above it notices. But the geological record shows what happens when accumulated stress is released rapidly. During the 1857 Fort Tejon earthquake, estimated at around magnitude 7.9, approximately 220 to 225 miles of the San Andreas ruptured. At Wallace Creek in the Carrizo Plain, the landscape shifted by approximately 30 feet, around 9 meters. That's roughly the length of a school bus. Studies of the Carrizo section have estimated long-term slip rates around 34 mm per year. 34 mm sounds insignificant. Over 1,000 years, however, that rate would amount to roughly 34 meters. Today, scientists don't need to wait for another 1857-scale earthquake to detect movement. USGS and partner institutions use GPS stations, seismic networks, geological mapping, and increasingly detailed remote-sensing measurements to watch California's fault systems. And those observations feed into another question. Not whether California will experience major earthquakes again, but where, how large, and with what consequences. 3. THE EARTHQUAKE CALIFORNIA HAS ALREADY MODELLED Scientists cannot predict the exact date of California's next major earthquake, but they can calculate probabilities and model realistic scenarios. The USGS Uniform California Earthquake Rupture Forecast estimated a 60% probability of at least one magnitude 6.7 earthquake in the Los Angeles region during a 30-year period. The estimated probability of magnitude 7 or greater was 46%. For magnitude 7.5 or greater, 31%. Former USGS seismologist Dr. Lucy Jones became one of California's most recognizable earthquake researchers, partly because of work translating numbers like these into something people could understand. Jones played a major role in the USGS ShakeOut scenario. The scenario modeled a scientifically plausible magnitude 7.8 earthquake on the southern San Andreas. It wasn't a prediction. Researchers instead asked what would happen if an earthquake consistent with California's known geology occurred today. The consequences extended far beyond collapsed structures. Water pipelines, transportation corridors, electrical infrastructure, communications, fires, emergency response. The exercise also helps correct one of California's biggest earthquake myths. The San Andreas is roughly 800 miles long, but only about 10 to 12 miles deep. According to USGS, its physical dimensions make earthquakes much larger than approximately magnitude 8.3 extremely unlikely on this fault. California doesn't need a fictional magnitude 10 earthquake to have a serious problem. Its real faults are already large enough. 4. The Caldera That Dropped 2.4 Inches On January 13, 2026, USGS geophysicists Josh Crozier and Alicia Hodovec-Ellis reported a measurable change at Long Valley Caldera. GPS stations showed its central area had subsided approximately 2.4 inches, 6 centimeters, since 2021. USGS described it as the most significant subsidence there since detailed measurements began in the 1980s. Long Valley measures roughly 20 miles long and 10 miles wide, and formed approximately 760,000 years ago during the Bishop Tuff supereruption. But the recent measurement came with an interesting contradiction. USGS reported that 2025 was unusually quiet seismically at Long Valley. Only six earthquakes of magnitude 1 or greater were located inside the caldera monitoring area that year, the first year since 1980 with fewer than 10. So scientists measured deformation without a corresponding surge in earthquakes. USGS does not interpret this as evidence that another supereruption is approaching. That's what makes the measurement interesting. Researchers can now watch an enormous volcanic system change by centimeters. 5. The Valley Still Sinking Today California's largest subsidence problem isn't volcanic, it's connected to groundwater. Historically, parts of the San Joaquin Valley have sunk nearly 30 feet because groundwater pumping compressed underground sediments. And recent measurements show the problem hasn't disappeared. NASA's 2025 satellite study detected subsidence reaching approximately 20 centimeters per year in fast-sinking Central Valley locations during the 2015-2023 observation period. In April 2025, USGS also highlighted its updated Central Valley Hydrologic Model, which can simulate groundwater, surface water, agricultural demand, and subsidence decades into the future. USGS hydrologist Michelle Sneed spent roughly 25 years studying this process. The mechanism is straightforward. Remove enough groundwater and underground pressure falls. Fine-grained sediments compress, and the surface above them sinks. Some compaction can be permanent. California isn't simply losing groundwater. In certain locations, the underground reservoir itself is physically changing. 6. The Aquifer That Cannot Fully Recover That permanent compaction creates another problem. An aquifer can lose storage space. When groundwater returns after drought, some compressed sediments rebound. Others don't. NASA-backed research has shown that decades of excessive pumping have permanently reduced groundwater storage capacity in parts of California's Central Valley. Former NASA JPL scientist Tom Farr and other researchers have used radar observations to connect groundwater loss with surface deformation. This means a wet year doesn't necessarily reset California's groundwater system. Water can return. Collapsed pore space may not. 7. The Landslide NASA measured moving 4 inches per week. In January 2025, NASA JPL released another remarkable California measurement. This time, the target wasn't an aquifer or volcano. It was the Palos Verdes Peninsula in Los Angeles County. NASA's airborne UAVSAR radar had flown over the region during fall 2024. Researchers compared multiple radar observations. What they found was dramatic. During a four-week period, portions of the active landslide area moved toward the ocean by as much as 4 inches, 10 centimeters, per week. Not per year, per week. The landslide complex itself is not new. Parts of Palos Verdes have been moving for at least six decades. But NASA found that the active area had expanded following record rainfall in Southern California in 2023 and another wet winter in 2024. Radar allowed scientists to see the movement across a large residential area. This is exactly what modern geological monitoring can do differently. A landslide doesn't need to collapse suddenly for researchers to watch it move. They can measure the slow failure while it's happening. 8. The Fault Beneath the East Bay San Francisco's earthquake problem isn't limited to the San Andreas. Across the Bay Area lies the Hayward Fault. It passes through one of California's most heavily developed urban corridors. USGS developed the Haywired scenario around a scientifically plausible magnitude 7.0 Hayward Fault earthquake. Again, the goal wasn't prediction, it was consequence modeling. What happens when an urban earthquake damages roads while simultaneously breaking pipelines? What happens when electrical interruptions affect communication? What happens when fires begin while transportation routes are compromised? California's risk comes partly from the fact that multiple fault systems cross densely populated areas. The San Andreas is the famous one. It isn't the only one that matters. 9. The Other Fault Moving Southern California east of Los Angeles lies the San Jacinto Fault System. It accommodates part of the relative motion between the Pacific and North American plates. This is one reason describing Southern California as simply the San Andreas Fault misses much of the geology. Tectonic strain is distributed across a network. USGS and Caltech monitor that network using dense seismic instrumentation. Tiny earthquakes help map structures underground. GPS measurements track gradual crustal motion. Larger earthquakes show where accumulated stress has been released. And in February 2026, the California Volcano Observatory even published a new explainer examining how researchers distinguish tectonic earthquake swarms from potentially magmatic swarms. That's important in California because faults and volcanic systems sometimes occupy the same regions. A cluster of earthquakes does not automatically mean magma. Scientists examine location, migration, deformation, depth, and other measurements before determining what a swarm may represent. 10. The Young Volcanoes Beside the Salton Sea, near the southern San Andreas, sit the Salton Buttes. Their most recent eruption occurred only about 1,800 years ago. USGS says the geothermal field beneath them is heated by zones of partially molten rock at depth. The region also experiences frequent earthquakes and has been monitored seismically for decades. But current context matters. In 2026, California's monitored volcanoes remained at normal-slash-green background status. That means researchers are monitoring a young volcanic system without evidence that an eruption is imminent. And beneath the same region, hot fluids are carrying something valuable. 11. The Lithium Beneath the Salton Sea The Salton Sea geothermal system contains extremely hot, mineral-rich brines. Those fluids also contain lithium. A US Department of Energy assessment estimated that geothermal operations were bringing brines containing the equivalent of roughly 21,500 tons of lithium per year toward the surface. Although that doesn't mean all of it is currently recovered commercially. The idea is to extract lithium while geothermal plants generate electricity from the same underground fluids. That's why the region is increasingly called Lithium Valley. California's underground geology isn't always a hazard. Sometimes the heat beneath it is a resource. 12. The Underground Heat, Powering 270,000 Homes About 100 miles northeast of Bakersfield lies the Koso Volcanic Field. It covers approximately 150 square miles, 400 square kilometers. Its underground heat is already being used. According to USGS, the Koso geothermal system can produce enough electricity for roughly 270,000 homes. Koso is also one of the California-Nevada volcanic regions where USGS identifies partially molten rock underground. Again, magma existing at depth doesn't mean an eruption is approaching. It means California's volcanic systems still contain heat, and scientists continue measuring them. 13. The Volcano That Erupted in Modern California California doesn't need prehistoric evidence to prove it can erupt. Lassen Peak erupted between 1914 and 1917. The broader Lassen Volcanic Center has produced hundreds of eruptions across approximately 200 square miles during the past 825,000 years. Some are remarkably recent. Chaos Crags erupted around 1,100 years ago. Cinder Cone around 1666. Lassen Peak began erupting in 1914. Today, the region contains hot springs, steam vents, boiling mud pots, and geothermal activity. And researchers are still watching it. The July 2026 CalVO update reported Lassen at normal background levels, alongside California's other monitored volcanoes. That's exactly why monitoring matters. Scientists aren't waiting until a volcano looks dangerous. They're building years of baseline data before anything unusual happens. We've now gone from a 2025 NASA satellite study to a 2026 USGS Long Valley measurement. A landslide moving up to 4 inches per week, sinking groundwater basins, active faults, geothermal fields, and young volcanoes. So, here's the question. Which recent measurement surprises you most? The 6-centimeter change at Long Valley? The 8 inches per year Central Valley subsidence? Or the Palos Verdes landslide moving 4 inches in a single week? Tell us below. And if you want more stories built around what NASA, USGS, NOAA, and researchers are actually measuring, subscribe to DiscoverTube. Because California's northern edge brings us to something much larger. 14. The 18-Mile Volcanic Corridor Along the eastern Sierra Nevada lies the Mono Inyo volcanic chain. The mono craters extend for approximately 18 miles and contain more than 30 eruption centers. The Inyo system adds another chain roughly 7.5 miles long. Many of these domes, craters, obsidian flows, and vents formed during the Holocene, the geological epoch we're still living in. That makes this volcanic landscape young. But Long Valley's recent monitoring provides useful context for the entire eastern Sierra. Researchers aren't simply mapping ancient volcanic rocks anymore. They're combining geological evidence with modern earthquake networks and GPS stations. The landscape shows where eruptions happened. The instruments show what is happening now. 15. The High-Threat System Near Clearlake North of San Francisco lies the Clearlake Volcanic Field. Mount Canocte rises approximately 3,200 feet above Clearlake, while the most recent eruptions in the volcanic field occurred roughly 8,500 to 13,500 years ago. USGS classifies Clearlake as a high-threat potential volcanic system. Partially molten rock remains beneath the broader region. During one week in July 2026, USGS also recorded 85 earthquakes above magnitude 1 at the nearby geyser's geothermal field. The largest was magnitude 3.1, yet California's monitored volcanoes remained at normal levels. That's an important distinction. Earthquakes alone don't mean an eruption is approaching. 16. The Creek Showing California's Movement at Wallace Creek The 1857 Fort Tejon earthquake shifted the channel roughly 30 feet sideways. Geologist Carey Sia and other researchers used locations around the Carrizo Plain to reconstruct prehistoric earthquakes and estimate long-term San Andreas behavior. But 30 feet represents only one event. Matching volcanic rocks on opposite sides of the fault indicate that the pinnacle's volcanics have moved roughly 196 miles 315 kilometers northward relative to related Neenoch volcanic rocks. One earthquake moves California feet. Plate tectonics moves it hundreds of miles. 17. The Faults Hidden Beneath the Pacific Much of California's tectonic system can't be seen from land. Researchers use sonar, bathymetry, seismic imaging, and other geophysical techniques to map faults beneath the Pacific. Improved offshore mapping has revealed connections between fault segments previously treated separately. That's important because fault length affects potential rupture size. And farther north, much of the San Andreas itself disappears offshore before reaching Cape Mendocino. California's most famous fault is partly invisible. Near its northern end, it enters an even more complicated tectonic region. 18. The Magnitude 7.0 Reminder from 2024 On December 5, 2024, a magnitude 7.0 earthquake struck offshore near Cape Mendocino. It occurred close to one of North America's most complicated tectonic intersections, the Mendocino Triple Junction. Here, the Pacific Plate, North American Plate, and Gorda tectonic system interact. South lies the San Andreas. North begins the Cascadia subduction zone, and subduction zones are capable of producing earthquakes far larger than typical San Andreas events. The 2024 earthquake was a recent reminder that some of California's most important geological movement is happening offshore. 19. The Seven Regions with Melt Underground California Volcano Observatory identifies partially molten rock beneath at least seven monitored volcanic regions in California and Nevada. Medicine Lake, Mount Shasta, Lassen, Clear Lake, Long Valley, Coso, and Salton Buttes. California has also experienced at least 10 eruptions during the past 1,000 years. USGS says future eruptions are inevitable over geological time. But that statement needs context. As of July 2026, all monitored California volcanoes remained at Normal Alert Level and Green Aviation Color Code. California remains volcanically active. That doesn't mean an eruption is currently approaching. 20. The Technology Watching California Move The final discovery isn't a fault or volcano. It's the monitoring system. NASA and USGS can now measure geological movement that would once have been almost invisible. Satellite radar tracks subsidence across the Central Valley. Airborne radar measures landslides around Los Angeles. GPS stations detected Long Valley dropping approximately 6 centimeters since 2021. Seismometers record earthquakes too small for people to feel. And new satellite datasets allow scientists to compare years of ground movement across enormous areas. Put those measurements together and California stops looking like a fixed landscape. Faults creep. Groundwater disappears. Sediments compact. Landslides move. Volcanic systems deform. Geothermal fluids circulate. And tectonic plates continue sliding. But the recent research also reveals something important. Movement does not automatically mean disaster. Long Valley experienced measurable subsidence while 2025 was unusually quiet seismically. NASA detected both sinking and rising land. California's monitored volcanoes remained at normal slash green in 2026. That's why the measurements matter. Scientists aren't simply asking whether California is moving anymore. They're asking how fast, where, in which direction, and is the movement changing? Here on DiscoverTube, those are the measurements worth following. So here's our final question. What do you think scientists will detect moving beneath California next? A fault? A volcanic system? Another sinking region? Or something completely unexpected? Tell us in the comments. And subscribe to DiscoverTube if you want to follow the next NASA, USGS, or geological discovery. Because California's mystery isn't whether the state is moving. Researchers have already measured that. The mystery is what moves next.