Hello and welcome to my earthquake section, this section is based on earthquakes only and all about them such as the Primary wave, Secondary wave, and the Surface wave. It also has the focus, epicenter, seismogram, seismograph, and the Ritcher scale.
EARTHQUAKES
An earthquake is the shaking of the ground caused by the sudden release of energy in rocks.
Primary wave
Primary waves travel the fastest of all three types of waves. Primary waves can pass through solids, liquids and gasses. Primary waves waves causes a slight vibration that might shake liquids and stuff on shelves. Primary waves can provide a warning that a earthquake is happening, and could give people a little time to prepare for the wave that will happen after.
Secondary wave
Secondary waves travel more slower than the primary waves. Secondary waves can pass through solids only but it can't go through any liquids or gasses.
Surface wave
Surface waves are the slowest of the three types of waves, but their rolling motions breaks roads and buildings .
Focus/Epicenter
A focus is were a earthquake begins and the location of the epicenter is directly above the focus. Some earthquakes have their focus in the Crust. A earthquake hypocenter is the location were the strain energy stored in the rocks is first released. making the point were the fault begins to shake. This occurs deep below the epicenter.
Seismogram/Seismograph
Seismologists use a special machine called a seismograph to measure earthquakes. Seismographs must be attached to a bedrock. Charles.F.Ritcher invented the Ritcher scale in 1935 in California at the Institute of Technology.