The U.S. Geological Survey Saturday reported an early-morning earthquake of 2.1 magnitude in parts of western Carroll County and eastern Frederick County.

The USGS said the epicenter was about three miles from Linganore, in Frederick County, and about 11 miles from Westminster in Carroll. A spokesman at Linganore Winecellars in Mount Airy said the vineyard had no awareness of the quake.

According to the Richter scale, a 2.0 magnitude earthquake is large enough to be detected but generally not felt. Quakes measured at between 2.0 and 2.9 on the scale can be felt but rarely cause damage.