Reduced human activity and displacement due to the pandemic of coronavirus resulted in a significant decrease in ambient seismic noise. These vibrations are generated by human activity and usually cause movements of the Earth’s crust. These have not disappeared but they are much less noticeable, reports CNN.
Our staff is teleworking. The earth continues shaking. Ground movements at frequencies 1-20 Hz, mainly due to human activity (cars, trains, industries, …) are much lower since the implementation of the containment measures by the government. #StayHome @ibzbe @CrisiscenterBE pic.twitter.com/pGgQAyLuUP
– Seismologie.be (@Seismologie_be) March 20, 2020
As a consequence of the phenomenon, certain minor seismic manifestations can now be detected by scientists. However, they would have gone unnoticed during normal human activity. The Brussels seismic center has thus gained in efficiency.
Between 30 and 50% less noise
Built in the city more than a century ago, the installation is usually “almost useless,” said Thomas Lecocq, geologist and seismologist at the Royal Observatory in Belgium. “Thanks to the silence of the city, it is almost as efficient as that in the basement,” analyzes the specialist, referring to an underground seismic station.
Since mid-March, the date of the containment of the inhabitants of Brussels and the closure of schools and non-essential shops, ambient seismic noise has dropped from 30 to 50% in the Belgian capital. The level recorded is similar to that which the seismologists observe on December 25, indicates Thomas Lecocq.
How the seismic noise on our little @raspishake seismometer running in West London (Twickenham) has been affected by the # covid19UK lockdown. This is a month of data for station R091F. The average noise levels are down reflecting fewer trains, buses and cars. pic.twitter.com/WmJLmAO18k
– Paula Koelemeijer (@seismo_koel) March 31, 2020
Researchers working in Los Angeles or in the west of London have made similar observations. In the British capital, a first drop was visible after the cessation of the activity of the schools and the places of gathering, explains the expert Paula Koelemeijer. Another fall then occurred after the government declared national containment.