Scientists moved to allay fears after an article reported a quake could send tsunami waves crashing over the coast of Washington and Oregon, and even trigger the eruption of volcano Mount Hood.
Locals fear it could be on the cards following a "seismic shift".
Superstation95.com reported a reading from an ocean data buoy showed the water level fell sharply, "signaling a land sink - the type of event often followed by a severe earthquake."
Details of the seismic scare emerged today as Express.co.uk also revealed how TWO large volcanoes erupted, causing 1,200 people to flee their homes in Indonesia and flights to be cancelled in Russia
Its report, said of the land drop: "This means a tectonic plate in the Ocean named the "Juan de Fuca Plate" has made a sudden, eastward movement and slipped beneath another tectonic plate named the "North American Plate.
"This type of event is usually followed by a massive upward movement of the North American Plate causing a very severe earthquake."
Washington has suffered quakes before and is due for one in the next 50 years GETTY
It said there had been an earthquake measuring nine on the Richter scale there in 1700, adding: "If such a thing were to happen today, thousands of people would be killed as a wall of water came ashore well inland passing Interstate 5 and destroying everything in its path from the beach to Interstate 5.
The report was circulated widely on Facebook and other social media, sparking online panic.
But, John Vidale, a seismologist and director of the Pacific Northwest Seismic Network, dismissed any claim an earthquake was on its way.
He said: "The claim that the water level changed isn't right. It was clearly misinformation that was presented as news."
He said any drop could have been triggered by a small wave or instrument malfunction.
The 1994 Californian earthquake devastated the region GETTY
Just like seismometers, what you see on one instrument is hugely considered unreliable and no other instrument showed anything, and the people watching these instruments immediately flagged it to ignore because it's so unlikely to be real.
Chris Goldfinger, director at Active Tectonics and Seafloor Mapping Laboratory and a professor at Oregon State University, confirmed there had been a reading from the buoy, but said it was not that unusual.
He said: "This interesting excursion in the water height at DART buoy 46404 is not a tsunami.
"The buoy is on the Juan De Fuca Ridge flank, not in the subduction zone, so I'd guess this might be a magma chamber deflation event."
The State of the Climate Summary Information is a synopsis of the collection of national and global summaries released each month.
« November 2015
Global Summary Information - December 2015
2015 is Earth's warmest year by widest margin on record;
December 2015 temperature record warm
The globally averaged temperature over land and ocean surfaces for 2015 was the highest among all years since record keeping began in 1880. During the final month, the December combined global land and ocean average surface temperature was the highest on record for any month in the 136-year record.