(TRINIDAD, Colo.) — The U.S. Geological Survey (USGS) reported that an earthquake with a magnitude of 3.4 occurred just north of Trinidad a little after midnight on Saturday, Oct. 26. According to the USGS website, 18 people reported that they felt light shaking from the earthquake in the area north of Trinidad. Courtesy: FOX21 News File Photo Earthquakes are not common in most of North America east of the Rocky Mountains, according to USGS. Those that do occur are mostly as faulting within bedrock, usually miles deep. Few earthquakes east of the Rockies are linked to mapped geologic faults such as in California's San Andreas fault system, where earthquakes are more common.