Explainer: Earth Tremors and earthquakes simplified

At around 7.00 p.m on Sunday evening, Kenya was shaken.

A 4.8-Richter-scale magnitude tremor reverberated across the country and was felt in Nairobi, Mombasa, Taita Taveta, Machakos, Nakuru, Nyeri, and Kiambu counties.

Those who were indoors at the time said they saw objects moving for the three seconds the tremor lasted.

Just felt an earth tremor in Langata. Who else felt it? ????

— Gathoni (@I_am_Gathoni) March 24, 2019

Social media instantly was abuzz with ‘seismic analysts’ to outsmart each other. Some said it was an earthquake, others a tremor.

But was it really?

According to the United States Geological Survey, a website that provides details about the natural hazards that threaten lives, what Kenya experienced last night was a tremor of magnitude 4.8.

The tremor was linked to an earthquake that struck Indonesia earlier on Sunday.

Difference between Earth Tremors and Earthquakes

Simply put, an earth tremor is a sudden shaking of the ground that causes destruction, as a result of movements within the earth's crust or volcanic action. It is of a smaller magnitude compared to an earthquake.

Tremors and quakes are measured with a seismograph.

An earthquake, on the other hand, refers to the violent shaking of the earth surface, resulting from the sudden release of energy in the Earth's lithosphere that creates seismic waves.

Earthquakes can range in size from those that are so weak that they cannot be felt to those violent enough to toss people around and destroy whole cities.

A large earthquake from afar will feel like a gentle bump followed several seconds later by stronger rolling shaking that may feel like sharp shaking for a little while.

A small earthquake nearby will feel like a small sharp jolt followed by a few stronger sharp shakes that pass quickly.

According to USGS, here’s what to do after an earthquake has occurred:

• Expect aftershocks hours, days, or weeks after the main quake.

Aftershocks can cause building damage and falling debris that could injure you.

• Avoid open flames in damaged buildings.

Earthquakes can damage gas lines, so don’t use lighters or matches.

• If you live near the coast, stay away from the beach.

Earthquakes can cause dangerous tsunamis and flooding.

• Drive carefully and plan alternative routes.

Structural damage and traffic light outages may make it difficult to get to your destination.