Earthquakes, natural and human causes

in this coloured photo you can see, on the right, a globe, and on the left, a stock chart like an electrocardiogram

The human race causes  50% of all earthquakes. We can thank the coronavirus pandemic for making this fact into headline scientific news.

There is the age-old question we all have been asked or thought: “What would happen to our planet if every human jumped at the same time”. Even popular physics and science programs and magazines have tried to explain the answer (such as Vsauce on YouTube).

We all exert a weight on the Earth, and the closer or further our weight to the centre of the earth depends on the overall effect. However, our total combined weight, compared to the overall weight of the earth, means that our physical movements on this planet are very small. Nevertheless, if masses of us humans jump, at the same time, and in close proximity, we all can cause a small and detectable seismic activity. If every human in the world jumps at the same time, our overall weight will be spread out over the entire earth and will not cause any great and devastating results, not even close. Highly populated areas, like cities, might detect some small seismic activity, but we won’t be bringing down buildings.

So how is it that the pandemic has recently shown us humans are causing 50% of earthquakes? I must point out here, that the word ‘earthquake’ is actually meaning any small detectable seismic activity.

It is not us humans directly, which are causing seismic activities, but the activities we are doing, and what we are using: machines and explosives. There are thousands of airplanes landing every day, from fully booked flights filled with people and luggage, to cargo airplanes. Have you every felt the slight shaking of the train station when a train zooms past? Towns near mining activity are often feeling small seismic movements. Traffic in the cities, with the weight of cars and trucks, moving about, continually dispersing weight on the roads. Even large ships, the heaviest machines of man, docking into a harbour causes shaking of the earth.

We humans are shaking our planet every day, all over the world, due to our activities. As the pandemic caused mass halting of human activities, Seismologists have been witnessing mass quietening of the earths fragile crust. This was experienced by all seismic measuring points as each country closed their factory doors.

For the first time, Seismologists have been able to measure seismic activity caused solely by the earth, and not by us humans.