About the Lithosphere
The Earth consists of many layers ranging from the mantle to the atmosphere, and all of it works together perfectly. The lithosphere is actually the thin, solid layer of the Earth, which comprises the crust and upper mantle. In other words, the lithosphere is made up of solid rock, which is the Earth’s outer surface, and magma, the hot liquid center of the Earth.
The Layers of the Lithosphere
The crust is made up of three different types of rock, igneous, sedimentary and metamorphic. Igneous rock is created after fissures or cracks open up in the Earth, or a volcano erupts releasing magma. Magma is superheated rock in liquid form, and when it erupts out of a volcano, it is known as lava.
The constant eroding from weathering agents like wind, water and ice creates sedimentary rocks. Smaller pieces of rock break off from larger pieces and turn into sand, pebbles, gravel and clay. These little pieces of rock may travel down streams or rivers before settling into place and forming into solid pieces of sedimentary rock. This process takes many years. Some 70% of rocks on Earth are sedimentary.
Rock that changes form due to the extreme heat, pressure and chemical reactions found in the Earth’s core are called metamorphic rock. The change takes place starting at 7.4 miles to 9.94 miles beneath the surface, at a temperature of 212 degrees Fahrenheit to 1,472 degrees Fahrenheit. Any type of rock that changes to another form is called metamorphic rock.
Magma makes up a very important part of the lithosphere. In fact, magma is responsible for the renewal of the Earth’s surface and its appearance over time. With the constant changing of rocks and new lava flows forming land, the Earth refreshes itself almost on a daily basis. Earth’s Structure Vocabulary Terms, Terrie Schultz
Lithosphere Interesting Facts
There are some interesting facts about the lithosphere, including how much it is responsible for Earth’s changes; in fact, the Earth wouldn’t change at all if it weren’t for it. When volcanoes erupt, they may leave devastation behind but over the long term, new plant life will emerge - even those never before seen. The lithosphere keeps the Earth vibrant and ever changing and able to sustain life.
The lithosphere is broken up into plates, a dozen large ones and several smaller ones, and the continents sit on top of these plates. These plates move relative to each other at rates of about 5 cm to 10 cm a year causing movement of the Earth. These plates’ movement or plate tectonics are what cause earthquakes around the globe. Exploring Plate Tectonics and Geologic Rock Formations, Kimberlee
The lithosphere was actually discovered by seismology; in other words, by listening to the movement of the Earth’s crust through earthquakes. While listening to fast earthquake waves, scientists discovered that the top mantle is just as rigid as the crust, although they have a different chemical makeup. The lithosphere is approximately 74.56 miles thick under the continents and is thinnest under the oceans at a few miles.