The seismograph and the seismoscope are the two main instruments used to measure the strength of earthquakes. The seismoscope is a simple instrument that measures the time that an earthquake takes place. The seismograph records the motion of the ground during an earthquake.
A seismograph's main component is a hanging mass — as heavy as 1,000 pounds — that is connected to a pen, and this large pendulum is situated just above a paper surface. When the ground moves, so does the paper, which rubs against the pen and marks the movement. Seismographs are isolated and connected to bedrock to ensure that the data they receive is not affected by the movement of surrounding objects. Advanced technology improves the accuracy of the seismograph and makes it sensitive to minute ground movements.Learn More
A diagram that uses the Richter scale is used to measure the magnitude of an earthquake. When an earthquake takes place, a device called a seismograph records the earthquake's vibration, and multiple seismographs can form a coherent picture. From the resulting diagram, the earthquake's force can be determined.Full Answer >
The Richter scale is used to quantitatively measure the magnitude of an earthquake. This tool was devised by the seismologist Charles F. Richter in 1935.Full Answer >
The Chinese seismograph was an instrument developed in 132 A.D. by the Chinese philosopher Chang Hêng to detect earthquakes and determine the direction from which they came. It was a brass instrument decorated with eight dragons, each holding a copper ball. On the base were eight frogs, each with their mouth open, to catch the ball when it drops.Full Answer >
A seismogram is interpreted when geologists look at squiggly lines made by a seismograph on a piece of paper, according to Michigan Technological University. Initial waves, called P waves, are small and close together because they travel quickly. More intense waves, called S waves, are next followed by surface waves that show up as the largest markings on a seismogram.Full Answer >