Travis Hilliard was at home watching TV late Friday night when he felt his house shake.
"I thought it was a bomb," said Hilliard, a Steamboat Springs resident. "After I realized that it wasn't a bomb, I thought someone was drunk and hit my house. When I realized it wasn't an accident, I finally thought it was a earthquake."
Hilliard, who is from Florida, didn't think earthquakes occurred in Colorado.
"Well, now I know," he said Saturday.
He's likely not alone in his newfound knowledge.
A magnitude 4.1 earthquake jolted Steamboat at 11:57 p.m. Friday and undoubtedly shook a few nerves.
The earthquake's epicenter was determined by the U.S. Geological Survey's National Earthquake Information Center to be about 14 miles east-northeast of Steamboat.
Felt at least as far south as Toponas, the quake originated about 3.1 miles below the Earth's surface, according to the USGS.
Chuck Vale, Routt County's emergency management director, said no damage or injuries were reported as a result of the quake.
"There is no concern anywhere," he said. "Everyone and everything is just fine."
As a precaution, Vale ordered a structural check on local dams, including Stagecoach Reservoir and Steamboat, Pearl, Catamount and Long lakes.
The tremor certainly got the attention of Routt County residents. Vale said the Routt County Communications Center, which answers all 911 calls made in the county, received about 180 calls in a one-hour period after the earthquake struck.
Most residents were concerned about whether they should be alarmed about the occurrence of an earthquake and how they should respond, particularly because the phenomena is fairly rare in the area.
"Most people just shrugged it off," Vale said. "We're ready for the next one."
Despite the high number of calls to dispatchers, Steamboat Springs police officers did not need to respond to any earthquake-related calls, Officer Josh Carrell said.
Yampa Valley Electric Asso--ciation and Atmos Energy officials didn't report any gas or power failures or problems. Downtown merchants didn't report any broken merchandise or damage to their stores.
"Everything was just fine when we came in this morning, even though the guests in the store were all talking abut how shocking the news was," said Into the West employee Betty Hilliard, Travis' mother. "I slept right through it."
Steamboat resident Joan Allsberry is from California, so she knows all too well what earthquakes feel like and the damage they can cause. But even she wasn't convinced that Friday's seismic activity was an earthquake.
"It was such a quick jolt," she said. "I thought for sure it was an explosion, not an earthquake."
California earthquakes, she said, generally last longer and create more of a rolling sensation. Steamboat's earthquake wasn't long enough to make her panic.
"It was a little bit of entertainment for us Californians," she said.
Like Travis Hilliard, many residents described the feeling of Friday's quake as if a car had hit their house.
"That's funny," said USGS geophysicist Don Blakeman. "Because that is exactly what an intensity level of four should feel like -- a car hitting your house."
Blakeman, who was monitoring seismic activity around the globe from the USGS's Golden office Friday night, said earthquakes are measured on two scales -- the Richter Scale, which measures seismic activity, and an intensity scale, which is a measurement of what people report feeling from the earthquake.
"Colorado does have about 15 or 20 earthquakes a year, but typically they are smaller than this one," Blakeman said.
Blakeman estimated the epicenter of the earthquake to be two or three miles east-northeast of Buffalo Pass on the southwest side of North Park. The earthquake would have felt stronger to anyone in that area, he said.
Local geologist Bill Bowes said the Steamboat Springs area is not on a direct fault line, but there are small ones that surround the area.
The last earthquake recorded in the Steamboat area was in April 2002, Blakeman said. A February 2000 earthquake of magnitude 3.0 was centered south of Wolverine Lake in the Mount Zirkel Wilderness Area, about 15 miles north-northeast of Steamboat. A magnitude 2.5 earthquake was recorded in 1993, and a magnitude 3.5 quake was reported in 1974.
Earthquakes are caused by the release of pressure built up in the Earth's crust, either from tectonic-plate movement or the transfer of pressure along fault lines. The released pressure creates energy that travels in waves. Friday night's earthquake, which lasted only a couple of seconds, could have resulted from pressure that was building for tens, hundreds or thousands of years, Blakeman said.
The quake could be a precursor to a larger tremor, Blakeman said, though that would be unlikely. No aftershocks were reported as of Saturday afternoon.