A once-overlooked fault line beneath North America may pose a far greater threat than previously realized. Canadian geologists have raised the alarm over the Tintina Fault, a hidden seismic hazard stretching from Yukon Territory into interior Alaska, that could potentially unleash a magnitude 7.5 earthquake or greater without warning.
The newly spotlighted fault could impact communities across Alaska, British Columbia, Alberta, and Montana, with experts warning of serious consequences for infrastructure and public safety.
Hidden Danger Building Beneath Alaska And Canada
First identified in 1912 by geologist J. B. Tyrrell, the Tintina Fault has remained largely under the radar due to its quiet geological history. Now, using advanced satellite and drone-based mapping techniques, scientists have discovered that the fault has been building up stress for thousands of years.
According to Dr. Michael West, state seismologist at the Alaska Earthquake Center, this system has been “quietly building toward a potentially very large earthquake.” Recent research suggests the fault may have accumulated about 20 inches of slip, a significant displacement that could be released in a single catastrophic event.
The fault runs beneath critical infrastructure, including highways, rivers, and the Trans-Alaska Pipeline, putting thousands of people and key systems at risk.
Evidence Points To A Violent Seismic History
The study, published in Geophysical Research Letters, used drone laser scans and 3D modeling to analyze ancient geological formations. In one area, scientists observed that a 132,000-year-old terrace had been displaced sideways. Elsewhere, they documented a shift of over 4,100 feet in the Flat Creek Beds, which date back 2.6 million years. These massive displacements suggest that the Tintina Fault has ruptured multiple times in the distant past with immense power.
Despite this dramatic evidence, the fault remains largely absent from official hazard models, including the USGS’s 2024 Alaska model. Lead author Dr. Theron Finley, a recent PhD graduate from the University of Victoria, emphasized that the landscape itself tells a different story. He noted that the fault is likely in the late stage of a seismic cycle, quietly gathering energy for its next rupture.
The Threat Of An Overlooked Fault Line
What makes the Tintina Fault particularly dangerous, according to researchers, is not just its potential to produce powerful earthquakes — it’s that “no one’s been paying attention to it,” as Dr. West put it. While faults like San Andreas are widely studied and monitored, Tintina has remained in the geological shadows, despite its capacity for widespread devastation.
This quiet period is not necessarily reassuring. Dr. West warned, “We are not good at thinking about things that happen every 12,000 years,” yet it’s precisely over such timescales that the fault accumulates the kind of pressure needed to cause major earthquakes. The last known rupture occurred more than 12,000 years ago, and geological clues suggest it may now be nearing another.
Infrastructure, Preparedness, And Potential Impact
A rupture along the Tintina Fault could devastate roads, pipelines, and even trigger landslides, particularly in remote communities with limited access to emergency resources. The Fairbanks North Star Borough in Alaska, home to over 125,000 people, lies within the potential impact zone. A quake of magnitude 7.5 or higher could significantly damage the Trans-Alaska Pipeline, a vital artery for energy transport in the region.
With few monitoring systems currently tracking activity along the fault, and the absence of any real-time early warning mechanism, researchers urge a shift in focus. Dr. West and his colleagues stress that the Tintina Fault demands more scientific attention, investment, and inclusion in national seismic hazard maps.
Source link
