Scientists have known about the Riasi fault in Kashmir, but it was not thought of as much of a threat as other, more active fault systems.
However, following a magnitude 7.6 earthquake in 2005 on the nearby Balakot-Bagh fault, researchers began scrutinising other fault systems in the region.
What they found is that the Riasi fault has been building up pressure for some time, suggesting that when it does release or "slip", the resulting earthquake may be huge -- as much as magnitude 8.0 or greater.
"What we set out to learn was how much the fault has moved in the last tens of thousands of years, when it moved, and how different segments of the fault move," said lead author of the study Yann Gavillot, who did much of the work as a doctoral student at Oregon State University in the US.
"What we found was that the Riasi fault is one of the main active faults in Kashmir, but there is a lack of earthquakes in the more recent geologic record,” Gavillot noted.
"The fault hasn't slipped for a long time, which means the potential for a large earthquake is strong. It's not a question of if it's going to happen. It's a matter of when," Gavillot said.
Results of the new study have been published online by the Geological Society of America Bulletin.
"The Riasi fault isn't prominent on hazard maps for earthquake activity, but those maps are usually based more on the history of seismic activity rather than the potential for future events," study co-author Andrew Meigs, professor at Oregon State University said.
"In actuality, the lack of major earthquakes heightens the likelihood that seismic risk is high," Oregon State University noted.
Gavillot said the potential for destruction of the impending earthquake is much greater than the 2005 earthquake.
The 2005 Kashmir earthquake killed about 80,000 people in Pakistan and India.