If you thought you felt a rumble overnight in the Glenwood Springs area, you probably weren’t imagining it.

According to the USGS, two earthquakes occurred in the area in the early morning hours of Tuesday, December 11.

The first earthquake occurred at 3:02 AM, reaching a magnitude of 3.4. This earthquake was detected just over a mile northwest of Glenwood Springs.

The second earthquake occurred roughly an hour later, at 4:13 AM, reaching a 3.6 magnitude. Though more powerful, it was a bit further from Glenwood Springs – close to four miles away in the same direction.

Earthquakes in the 3-4 magnitude range on the Richter Scale are generally not harmful, but may cause slight damage.