Two earthquakes in Iran kill 300 and injure 5,000 - World Updates | The Star Online

Two earthquakes in Iran kill 300 and injure 5,000 - World Updates | The Star Online

Always changing. The earth crust is not a still matter. Cooling of the earth strain the earth. When one half of the earth begin to cool, the half begin to heat. The rate of cooling and heating up has changed throughout the years with aggressive development. Revolution of the earth also strain the earth. Attractive forces within the solar system also strain the earth. Action produce reaction. Strains produce varied results in different parts of the world as the outer layer of the earth is not homogeneous. Extinct and active volcanoes mark the lines of the of earth weak edges. These weak edges can break. The breaks produce vibrations and the distances the vibrations travel would depend on the force of the break.