Over the past 2 weeks, earthquake “swarms,” some with magnitudes of 3.9, have been occurring beneath Yellowstone Lake. These “earthquake swarms,” a series of smaller earthquakes clustered within a short period of time, have occurred over five hundred times in the Yellowstone area from December 26th to January 1st. While smaller earthquakes are common in this area, the recent earthquakes show increased geothermal activity.

Five miles below the Yellowstone plateau is a subterranean chamber of magma and pressurized gas. The Yellowstone Caldera is often referred to as a “supervolcano” because of its immense size and especially large explosive eruptions. It is believed that the geographical features of the park are due to the most recent explosion of the volcano 640,000 years ago.

If the volcano were to erupt, the consequences could be devastating. An eruption of the predicted size would cover most of the country in ash, and all of the atmospheric dust could affect global climate. The head of the Yellowstone Volcano Observatory has proposed extending monitoring of the volcano, labeling it a “high threat” system. Over the next several months the volcano’s surveillance is of great importance, as is surveying the earthquake’s strength.

However, Hank Heasler, a National Park Service geologist, says that there is little to worry about. The volcano has not erupted for many years, and these earthquake swarms are not incredibly intense. Twenty years ago, the earthquake swarms reached 4.7 on the Richter scale. These swarms are only 3.9.

Sources:
http://www.msnbc.msn.com/id/17629668/
http://www.time.com/time/health/article/0,8599,1869313,00.html