Most of the quakes have been small enough that they haven't been felt by people, but the larger ones, including the most powerful one — 4.4 on the Richter scale — on June 15, certainly have.
Dr. Michael Poland, a research geophysicist at Cascades Volcano Observatory at the United States Geological Survey, told Sputnik that earthquake swarm at Yellowstone wasn't particularly extraordinary because about half of all earthquakes at Yellowstone occur as parts of swarms.
"The fact that the swarm on the western edge of the Park has been ongoing since June 12 is a little unusual — most swarms only last days to weeks — but it's not unprecedented. There was a swarm in 1985 that lasted for three months! So what is happening now is the sort of thing we expect from Yellowstone," Poland told Sputnik.
There are also earthquakes taking place northwest of Yellowstone in Helena, Montana, and neighboring Idaho.
"These events are related to faults in the region, and not related to Yellowstone. And we haven't seen any changes in other monitoring data from Yellowstone that might indicate a change in the status of the Yellowstone magmatic system due to these regional earthquakes," Poland explained.
The scientist also said that there is no reason to expect an eruption at Yellowstone, claiming that "Yellowstone activity remains 'normal.' There are no changes in ground deformation or thermal activity that suggest a change in the magmatic system, nor any truly anomalous earthquakes. Prior to an eruption, we would expect to see lots of earthquakes and very significant ground uplift, and that's just not happening right now."
Magma last flowed at Yellowstone 70,000 years ago and the last large eruption was 640,000 years ago. So while another large eruption is highly unlikely, a small hydrothermal explosion from one of the geyser areas could take place, which could be quite dangerous to those in the vicinity.
There is no reason to panic right now. "If a major eruption were imminent, there would be very strong earthquakes happening constantly — local residents and visitors would certainly feel lots of shaking, and we would see really major changes in other monitoring parameters," Poland told Sputnik.
Brian Wilcox of Nasa's Jet Propulsion Laboratory at the California Institute of Technology has suggested drilling into the volcano and using pressurized water to release the heat from the magma chamber, thereby neutralizing it. When asked whether this is a feasible option, Poland told Sputnik that even though the concept is interesting and could provide a lot of information about volcanoes through studying the rocks that are brought to the surface, drilling to prevent an eruption is unfortunately unrealistic.
"The potential for unintended consequences is vast and the approximations used to design the proposed drilling plan are approximate. So, the plan does not strike me as feasible," he opined.