seismology[sīz mäl′ə jē, sīs-]
Seismology is the branch of science that deals with earthquakes and the movement of the Earth's tectonic plates.
History of Seismology
- People begin to be curious about earthquakes and other Earth movements in the 1700s and early 1800s.
- One early theory about the cause of earthquakes was the theory of elastic wave propagation in solids - that you can hit a solid object and waves of energy will travel through the object and cause movement.
- In 1857 Irish engineer/scientist Mallet proposed the theory that earthquakes move outward from a central focal point, and that, by locating the direction that the earthquake came from, the focal points could be located and studied.
- Mallet also proposed the first earthquake monitoring system, suggesting that there should be observatories made that could study and monitor these earthquake activities and pinpoint where they were coming from and what might be causing them.
- In the late 1870s the first seismograph, which is a piece of equipment that uses ink and paper to measure the severity and duration of an earthquake or other seismic event, was developed by English scientists in Japan.
- In 1897, the first seismograph was installed in the United States, near San Francisco at the Lick Observatory. This seismograph was able to record the great San Francisco earthquake of 1906, allowing for further study of this massive event.
- Also in 1897, the first damper-equipped seismograph was created, which allowed for continuous study of a single earthquake event. This was made possible because the vibrations of the device could be controlled by the damper mechanism. This was a huge step forward over previous seismographic devices because it allowed for longer term studies of earthquakes and their aftershocks without having to reset the devices.
An example of seismology is geological surveying.
Origin of seismologyseismo- + -logy
- seis′mo·log′ic , seis′mo·log′i·cal
From Ancient Greek σεισμός (seismos, “earthquake”) and -λογία (-logia, “study of”).