# Scientists Find a Razor-Sharp Line of Earthquakes Hidden Beneath Alaska > Source: > Published: 2026-07-01 01:19:00+00:00 Back in 2002, a massive earthquake in central Alaska was felt as far away as Seattle. This giant earthquake even generated standing waves that damaged houseboats in Washington State. Known as the [2002 Denali earthquake](https://en.wikipedia.org/wiki/2002_Denali_earthquake), it was a seismic reminder of how much power lies latent beneath our feet, and just how far-reaching its impacts can be. Now, a team of seismologists has tracked down the potential origin of that quake. They've reported their findings in * The Seismic Record*, a journal of the Seismological Society of America. They used [machine learning](https://www.sciencealert.com/artificial-intelligence) to construct a catalog of earthquakes from data captured at stations near the central stretch of the Denali Fault and the Alaska Range suture zone. These earthquakes followed a clean line – or, as the scientists put it, a 'razor-sharp edge' – along the subducting Yakutat slab. Scientists already knew the Yakutat slab was subducting (sliding underneath) the North American plate, but they'd never been able to trace its edge in such clear detail. To complicate matters further, these aren't the only two hunks of Earth involved in the traffic jam: the Pacific plate is part of the collision, too. Some major faults in the North American plate add to the tectonic pile-up, including the Denali fault for which the 2002 earthquake was named. Lead author Meghan Miller, a seismologist at Australian National University, [says](https://www.seismosoc.org/news/thousands-of-new-earthquakes-define-the-razor-edge-of-an-alaskan-microplate/) the machine learning aspect of the study was essential to uncovering the Yakutat edge. This, she says, uncovered information hidden in the data that was difficult to see using traditional methods. That included the 250-kilometer-long chain of earthquakes (that's about 155 miles), stretching in a straight line northwest to southeast. "Thousands of small, previously undetected earthquakes form a prominent linear cluster that illuminates the precise edge of the subducted Yakutat microplate and defines the location of changing slab morphology reflecting the change in stress state," Miller and colleagues [report](https://doi.org/10.1785/0320250055). By exploring seismic noise data collected between earthquakes, the team were able to map the edge of the Yakutak plate in unprecedented detail. This revealed that the plate stretches much further beneath the North American plate than we previously knew. In fact, it even reaches below the Denali fault. The ongoing collision of plates creates massive mechanical stress in the region, and the way their structures are interacting, it seems, has a significant influence over the patterns of earthquakes and volcanoes in south-central Alaska. Miller and team think this congested intersection of plates set the stage for the [magnitude 7.9](https://en.wikipedia.org/wiki/2002_Denali_earthquake) 2002 Denali earthquake, which was the strongest shock ever recorded in the Alaskan interior. "We suggest that the northeastern margin of the Yakutat microplate, imaged here to be directly below the curved section of the fault, influenced nucleation of the 2002 event," the authors [propose](https://doi.org/10.1785/0320250055). They think the seismic stress of plate collision and subduction could have propagated up through the Denali fault. The findings also support theories that the Yakutat slab had a hand in forming the volcanic fields in the area, which are relatively young, geologically speaking. **Related: A Giant Seismic Wave Bounced Off Earth's Core And May Have Shifted Japan** "Considering the new data documenting the lateral extent of the subducted Yakutat microplate presented here, we propose that the Quaternary onset of volcanic fields around the northern and northeastern margins of the imaged Yakutat slab record re-establishment of a mantle wedge since around one million years ago," the authors [conclude](https://doi.org/10.1785/0320250055). The research was published in * The Seismic Record*. This article was fact-checked by [Carly Cassella](https://www.sciencealert.com/carly-cassella) and edited by [Peter Dockrill](https://www.sciencealert.com/peter-dockrill). While we pride ourselves on our process, we are only human. If you spot a mistake, [please let us know](https://www.sciencealert.com/contact-us).