An earth tremor is another term for an earthquake, although it is most commonly used to describe earthquakes of low intensity. Earthquakes are measured with tools called seismographs, and their intensity is rated on a logarithmic scale, called the Richter scale. The Richter scale is not useful for earthquakes that rank higher than a level 8 earthquake.Continue Reading
Earthquakes occur when the earth’s tectonic plates move and contact other plates. Sometimes the plates rub against each other laterally, while other times one plate moves underneath another. When this happens, it is called a subduction zone or a subduction-caused earthquake. In some particularly violent earthquakes, two plates collide into each other. This type of collision may even cause mountains to form, which happened millions of years ago when the Indian subcontinent crashed into Asia, producing the Himalayas.
Earthquakes are rather common, though few are strong enough to cause much damage. People may not even feel very weak earthquakes. The center of the disturbance is called the earthquake’s epicenter, and epicenters usually occur along major fault lines, where two plates contact each other. Many large and active fault lines occur around the margin of the Pacific Ocean, which has given the region the name “ring of fire” for all of the earthquakes and volcanoes in the region.Learn more about Earth Science
The one and only known home for life, Earth is one of the most interesting planets of the solar system. Life on Earth is extremely diverse; however, relative to Earth's size, all of life is contained within a very thin layer of its surface and lower atmosphere.Full Answer >
According to scientists, the earth is about 4.5 billion years old. However, because of the constant upheavals in climate, plate tectonics, asteroid strikes and other events, most of the evidence of the earth's beginnings are lost.Full Answer >
Scientists agree that the Earth formed about 4.6 billion years ago out of accreted matter from the solar nebula. All planets in the solar system formed the same way. Once the proto-Earth was formed, many changes occurred over vast timescales to produce the Earth of the 21st century.Full Answer >
While no one knows for certain how the Earth formed, scientists theorize that it formed over 4 million years ago after the sun went through its initial formation, gravity began to draw heavy particles together into a planet and solar winds blew away lighter gases. These heavy particles became the core of the planet. As the mass continued to grow, heavier particles sank to the center, according to Space.com.Full Answer >