2 (g) Inside Earth's layers
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A Journey to the Center of Earth
The three main layers of Earth are the crust, the mantle, and the core. These layers vary greatly in size, composition, temperature, and pressure. If you could travel through these layers to the center of Earth, what would your trip be like? To begin, you will need a vehicle that can travel through solid rock. The vehicle will carry scientific instruments to record changes in temperature and pressure as you descend.
Temperature; As you start to tunnel beneath the surface, the surrounding rock is cool. Then at about 20 meters down, your instruments report that the rock is getting warmer. For every 40 meters that you descend from that point, the temperature rises 1 Celsius degree. This rapid rise in temperature continues for several tens of kilometers. After that, the temperature increases more slowly, but steadily. The high temperatures inside Earth are the result of heat left over from the formation of the planet. In addition, radioactive substances inside Earth release energy. This further heats the interior.
The three main layers of Earth are the crust, the mantle, and the core. These layers vary greatly in size, composition, temperature, and pressure. If you could travel through these layers to the center of Earth, what would your trip be like? To begin, you will need a vehicle that can travel through solid rock. The vehicle will carry scientific instruments to record changes in temperature and pressure as you descend.
Temperature; As you start to tunnel beneath the surface, the surrounding rock is cool. Then at about 20 meters down, your instruments report that the rock is getting warmer. For every 40 meters that you descend from that point, the temperature rises 1 Celsius degree. This rapid rise in temperature continues for several tens of kilometers. After that, the temperature increases more slowly, but steadily. The high temperatures inside Earth are the result of heat left over from the formation of the planet. In addition, radioactive substances inside Earth release energy. This further heats the interior.
Pressure: During your journey to the center of Earth, your instruments record an increase in pressure in the surrounding rock. Pressure results from a force pressing on an area. Because of the weight of the rock above, pressure inside Earth increases as you go deeper. The deeper you go, the greater the pressure.
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Earth has three main layers—a crust, a mantle, and a core. The crust includes the solid, rocky surface. Under the crust is the mantle, a layer of hot molten rock. When volcanoes erupt, this hot material rises to the surface. Earth has a dense core made of mainly iron and nickel. The outer core is liquid, but the inner core is solid.
Earth is unique in our solar system in having liquid water at its surface. In fact, most of Earth’s surface, about 70 percent, is covered with water. Perhaps our planet should be called “Water” instead of “Earth”! Earth has a suitable temperature range for water to exist as a liquid, gas, or solid. Water is also important in shaping Earth’s surface, wearing it down and changing its appearance over time.
Earth is unique in our solar system in having liquid water at its surface. In fact, most of Earth’s surface, about 70 percent, is covered with water. Perhaps our planet should be called “Water” instead of “Earth”! Earth has a suitable temperature range for water to exist as a liquid, gas, or solid. Water is also important in shaping Earth’s surface, wearing it down and changing its appearance over time.
Plate Tectonics causes Mountains, Earthquakes and Volcanoes
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View this video to find out How Geologists obtain indirect evidence about the Earth's interior. |
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