DENISON, Tex. (KXII) - Several people said they felt the ground shake in Grayson County Monday, and that's due to four earthquakes.
All four earthquakes were recorded in close proximity to the North Texas Regional Airport.
There were no reports of damage in Grayson County, but lots of people were shaken up.
"I didn't know if it was actually an earthquake and when I learned, I was like, in Pottsboro?" said Skylar Watkins, who felt the earthquakes.
Skylar and her mom Sonya were home Monday afternoon.
"And I heard like a really loud noise, I guess the walls moving," Skylar said.
"At first I thought, oh my gosh, somebody just ran into the house," Sonya said.
But no one ran into her house, it was an earthquake.
"It felt like there was like something pounded in my attic, and I was like what the heck is happening," Skylar said.
The biggest jolt was a 2.8 magnitude earthquake around 4 p.m.
Geologists in Oklahoma and Texas recorded one before and two aftershocks, all with a magnitude of 2.2 or less and all in the same area near the North Texas regional airport.
"Another one was later on in the afternoon and it was kind of the same thing," Sonya said.
Several experts we spoke with said it's too early to determine what caused the earthquakes.
However, the U.S. Geological Survey said the main cause of recent earthquakes in the central part of the country is due to disposal of waste fluids that are a byproduct of oil production.
The Railroad Commission of Texas inspected two sites after a homeowner complained of damage from the quakes, however, they found no violations.
Those are just two of hundreds of oil and gas well sites in the area near the quakes.
"It was like this humongous shake. It felt like my entire house was just going to cave in," Sonya said.
Texas Seismological Network is in the process of analyzing the same four earthquakes recorded by the Oklahoma Geographical Survey on Monday.