A significant section of the North Anatolian Fault -- the seismic fault line that runs beneath the Sea of Marmara, off the coast of Turkey -- has grown eerily quiet in recent years, scientists say. And that could mean one of two things.

The less worrisome of the possibilities is that the two tectonic plates are gliding slowly, safely by. The other, more catastrophic option, is that a hangup has brought the two plates to a standstill, with seismic tension slowly building.

During a recent survey of the fault line -- including analysis of 20 years of GPS data -- seismologists from MIT and Turkey located evidence of both scenarios. While western portions of the line appear to be moving along without issue, scientists predict the seismic gap that lies five miles west of Istanbul is likely to produce large earthquake in the near future.

Researchers determined the particularly sticky segment of fault line should have slipped some eight to ten feet over the last 250 years -- but it hadn't.

"Istanbul is a large city, and many of the buildings are very old and not built to the highest modern standards compared to, say, southern California," Michael Floyd, an earth scientist at MIT, said in a press release. "From an earthquake scientist's perspective, this is a hotspot for potential seismic hazards."

Floyd says it's quite difficult to offer a timeline for when an earthquake is likely to occur. But, he says, when it comes, it's likely to be a magnitude 7 temblor or stronger.

"When people talk about when the next quake will be, what they're really asking is, 'When will it be, to within a few hours, so that I can evacuate?' But earthquakes can't be predicted that way," Floyd added. "Ultimately, for people's safety, we encourage them to be prepared. To be prepared, they need to know what to prepare for -- that's where our work can contribute."

The work of Floyd and his colleagues was detailed in a recent issue of the journal Geophysical Research Letters.