A 2.7-magnitude quake happened just after 5:30 a.m. A 3.3-magnitude quake happened at 5:36 p.m., according to the USGS.
Those quakes were followed by a third, 2.6-magnitude one just after 10 p.m. Thursday.
All were centered near Irving.
Chuck Chinnis works across from the old Texas Stadium site. He's felt six earthquakes in his office so far, but says the one on Thursday afternoon was by far the strongest.
He says they're getting worse, but is thankful there hasn't been damage.
At Toosdai Gipson's home off of Estes Road and West North Gate Drive, a piece of cardboard now covers a broken window, which shattered immediately after the shaking stopped.
Gipson says thankfully, the window is in the back bedroom, which no one was near at the time of the second quake.
In February, SMU scientists discovered a fault line running from Irving into northwest Dallas.
The fault runs northeast from Hwy. 114 to Walnut Hill Lane.
The scientists' equipment used to measure the quakes placed the quakes' centers about two miles from the old Texas Stadium site, where they originally thought the activity was centered.