GEOLOGY

Detailed explanation-1: -A seismograph is the primary earthquake measuring instrument. The seismograph produces a digital graphic recording of the ground motion caused by the seismic waves . The digital recording is called a seismogram. A network of worldwide seismographs detects and measures the strength and duration of the earthquake’s waves.

Detailed explanation-2: -Seismographs are instruments used to record the motion of the ground during an earthquake. They are installed in the ground throughout the world and operated as part of a seismographic network. The earliest “seismoscope” was invented by the Chinese philosopher Chang Heng in A.D. 132.

Detailed explanation-3: -The Richter Scale It used a formula based on the amplitude of the largest wave recorded on a specific type of seismometer and the distance between the earthquake and the seismometer.

Detailed explanation-4: -A seismograph is a machine which measures an earthquake.

Detailed explanation-5: -Because of the limitations of all three magnitude scales (ML, Mb, and Ms), a new more uniformly applicable extension of the magnitude scale, known as moment magnitude, or Mw, was developed. In particular, for very large earthquakes, moment magnitude gives the most reliable estimate of earthquake size.