One of the first, and rather unsettling things you learn in Secondary School Geography is that the Earth is unstable. In fact, that was the exact words the textbook used. It was quite correct, the earth is unstable as the land that we live on floats on a sea of magma lava. These land masses are called “plates”. These plates move and when they rub or even bang together we feel them as Earthquakes. There are very big plates and there are some that are not so big. These are the ones that cause all the issues as they wobble about, rubbing against the larger ones. This creates powerful tremors which can have destructive effects.
One of the first things that gets taken out is the electricity supply. This affects both over and underground grid networks so you might need a Diesel Generator to ensure that yours doesn’t end. Water supply can also be affected by an Earthquake.
In the UK we are lucky. We are far away from the Atlantic plate to only feel small tremors. However the West coast of North America is a very different story. Sat against the North American plate it is an active one known as the Juan De Fuca plate. It has caused no end of issues, namely the San Andreas fault.