WELD COUNTY - The USGS is reporting a 3.1 magnitude earthquake in Weld County.
9NEWS viewers contacted the station at 10 a.m. Sunday morning saying they had felt the earthquake in Greeley, Evans and LaSalle.
William Yeck, a research geophysicist at the National Earthquake Information Center says Sunday's earthquake occurred in roughly the same area as a quake in the summer of 2014.
"There's a sequence that started in 2014 around June 1," said Yeck. "It was a magnitude 3.2 and some earthquakes afterwards. Those were linked to wastewater injection. This earthquake occurred fairly close to that but we can't say if it's either a natural earthquake or a human caused earthquake."
Sunday's quake was felt as far away as Boulder according to the USGS, but wasn't large enough to cause any damage.
"Generally a 3.1 earthquake is a fairly small earthquake, not something that would cause a lot of concern in terms of potential damage," said Yeck. "People will definitely feel a jolt and it would be a quite a shock, especially if you live in the region near Greeley where earthquakes are very uncommon. You know suddenly feeling a shift in the ground is quite unexpected."
Yeck says in 2014 people described the earthquake like a truck hitting their house.
In the Denver area Yeck says earthquakes are rare.
"The exception was in the 60s and 70s there were a sequence of earthquakes called the Denver earthquakes that were induced by wastewater injection at the Rocky Mountain Arsenal," said Yeck. "That was actually the first case of earthquakes we knew were caused by humans injecting wastewater into the ground. Since then things have been really quiet
It could be months or even a year before a cause is determined for Sunday's quake.
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