No Significant Increase in Earthquake Activity In The Area

According to the United States Geological Survey

Some Jefferson County residents felt a seemingly increasingly familiar sensation last week as another minor earthquake shook the region. Though the epicenter of last week’s quake was not centered in Jefferson County, it is the fifth time that local residents have encountered a quake since the November 10th quake in Kentucky. The Jefferson County area was close to the epicenter of two November 24th earthquakes and the latest quake struck the Greenback area on December 5th. With the recent earthquake activity being felt in the area, some concern has arisen about the reasoning for increased activity in the area.

In actuality, there has been no significant increase in earthquake activity in the area, according to the United States Geological Survey, which monitors seismic activity in the United States and the World. In an interview with a staff Geo Physicist, he stated that recent earthquakes are not unique in the area. While earthquakes are not commonly felt as often in the Eastern portion of the United States, there is regular activity that is not always felt. Western Tennessee is on a more active fault, however, the mountainous regions of Eastern Tennessee, combined with TVA reservoirs, contribute to the activity in the local area. He suggested that the force of the Kentucky quake, coupled with the proximity to the epicenter of the November 24th quake, has raised awareness in the area. Most minor earthquake activity is not recognized by the general public, however the heightened awareness has brought the issue to the forefront. While the Kentucky quake and the first quake on November 24th exceeded 3.0 on the scale, the subsequent quakes registered less than 3.0.

California experiences 30-50 registered 2.0 or better quakes per day. Geo Physicists consider any quake less than 4.5 to be very minor and a quake would have to register 6.0 or better to cause real damage to the area. Large reservoirs that were created by TVA can, in themselves, create small earthquakes due to the extra stress caused by the weight of the water on the land. Older buildings, such as historic construction, fare much worse in a quake and those buildings and homes that are true brick construction have the greatest risk. Newer construction has met federal standards and it would require a significant quake to present damage.

Though local residents may be more aware of activity in the area, recorded seismic activity shows no marked increase in the area, according to USGS. Geo Physicists at the USGS did note that any activity in the Eastern United States appears to have further reaching impact than was previously thought. The geological structures and rock prosperities in the Eastern United States appears to be the reason for the increased sensitivity in the area. Research is ongoing concerning the differences in the reactions of various regions of the United States and should be presented later this month

Source: K. Depew, News Director