In 1935, Charles Richter found a way to measure earthquakes using a machine called a seismograph. It draws wiggly lines to show how much motion happens during an earthquake. Richter gave each quake a number with a 1 being very weak and 7 and over being strong. To this day, seismologists still use the Richter scale to measure an earthquakes power.
The numbers below shows how the magnitude and the intensity of earthquakes are related.1-2
Shaking is rarely felt by people.2-3
Only people at rest feel the shaking, especially if they are on the upper floors of a building.3-4
Many people indoors feel the shaking, but most people do not recognize it as an earthquake.4
Most people indoors and some outdoors notice shaking. Dishes, windows, and doors rattle. Walls creak. Parked cars rock.4-5
Felt by almost everyone. Many sleeping people wake up. Liquid splashes out of glasses. Small objects are knocked over. Some dishes and windows break.5-6
Felt by all. People have trouble walking. Some heavy furniture moves. Dishes break, and pictures fall off walls. No damage to buildings.6
People have trouble standing. Furniture breaks. Plaster and bricks may crack and fall. Noticeable waves on ponds. Church bells ring. Considerable damage to poorly built buildings.6-7
People have trouble driving cars. Walls, chimneys, and tree branches break and fall. Some poorly built buildings may collapse. Tall structures may twist and fall.7
People panic. Underground pipes may break, and well-built buildings are considerably damaged. The ground may crack.7-8
The ground cracks. Water splashes over the banks of rivers and canals. Railroad tracks bend.8
Highways, railroads tracks, bridges and underground pipelines are destroyed. Most buildings collaspe. Large cracks appear in the ground.8 or greater
Destruction of buildings and transportation systems. Almost everything is destroyed. The surface of the ground moves in waves or ripples. The ground is covered with cracks and holes.