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- Juab County got the shakes on Sunday night
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By Myrna Trauntvein
Times-News Correspondent
Yes, Nephi did have another minor earthquake on Sunday.
Monday morning, the US Geological Survey confirmed two small earthquakes had occurred overnight near Nephi.
The first was a Magnitude 3.7 that was followed by a Magnitude 3.2 tremor.
No damage had been reported and, to date, only 50 or so people have responded to the USGS National Earthquake Information Center question: "Did you feel it?"
The first quake was 3.7 magnitude at a 3km depth which occurred at 11:08 p.m. Sunday.
A short time later on December 28 2014, the second quake or aftershock occurred at 11:56 p.m.
According to the site maintained by USGS, the Magnitude Type was ml (Local Magnitude) commonly referred to as the "Richhter magnitude," and was located 12km (eight miles) WSW of Nephi.
A USGS seismologist has reviewed the status of the two minor quakes and has corraborated the data.
The USGS National Earthquake Information Center states that the Nephi-area historical earthquake activity is slightly above Utah state average. It is 113 percent greater than the overall U.S. average.
Also this month, a micro earthquake occurred at 7:18:53 p.m. (MST) on Wednesday, December 24, 2014.
The magnitude 0.9 event occurred four miles SW of Rocky Ridge, Utah and the hypocentral depth was 5 miles from the city.
According to the site, there have been 28 earthquakes in Utah the past year.
Those who would like to help the survey by responding to the question—"Did you feel it?"—should visite the site: http://earthquake.usgs.gov/research/dyfi/ and answer the few questions posed by the USGS National Earthquake Information Center.
On Friday, November 7, 2014 at 1:56 p.m. a M 2.7 event also occurred approximately 17 miles SSW of Nephi; Friday, November 7, 2014 at 1:57 p.m. a M 2.3 occurred 19 miles SSW of Nephi, Utah; November 7, 2014 at 3:24 p.m. a M 1.7 was located 16 miles SSW of Nephi, Utah.
By answering the "Did You Feel It?" questions, citizens contribute to earthquake science.
USGS is trying to tap the abundant information available about earthquakes from the people who actually experience them.
"By taking advantage of the vast numbers of Internet users, we can get a more complete description of what people experienced, the effects of the earthquake, and the extent of damage, than traditional ways of gathering felt information. And best of all, with your help we can do so almost instantly," states the information published at the site.
"By contributing your experience of the earthquake, either immediately afterward, or whenever it is possible for you to do so, you will have made a contribution to the scientific body of information about this earthquake. You will also ensure that your area has been represented in the compilation of the shaking map. This is a two-way street. Not only will you add valuable information on the extent of ground shaking and damage, but in the process we hope you will learn more about how other communities fared and gain a greater understanding of the effects of earthquakes."
There are two different ways to describe the size of an earthquake. One is magnitude (often described by the Richter magnitude ), which is related to the amount of energy released by the earthquake source. It is usually determined by measuring the amplitude (height) or by modeling the character of the earthquake waves recorded by a seismograph.
The second way of describing earthquake size is to measure earthquake effects. Intensity is a qualitative measure of the strength of ground shaking at a particular site. Currently used in the U.S. is the Modified Mercalli Intensity Scale. Each earthquake that is large enough to be felt will have a range of intensities. Usually (but not always) the highest intensities are measured near the earthquake epicenter and lower intensities are measured farther away.
Roman numerals are used to describe intensities to distinguish them from magnitudes.
For example, the magnitude of the Northridge earthquake was 6.7. The intensities ranged from IX (violent) close to the epicenter, to V's (moderate) at distances of about 60 to 200 miles away, and finally not felt at distances far away.
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