Earth's Crust and Layers
Planet Earth is made up of several layers of crust, but the three main layers are the mantle, the core, and the crust. The core is the center of earth made up on an iron-nickel alloy that has the same tempurature as the sun. The mantle is the layer above the core, seperating the inner and outer mantles. Earth's crust is above the mantle and is the Earth's hard outer shell.
The Asthenosphere
The asthenosphere is a portion of the upper mantle between the lithosphere and is involved in plate tectonics movement. Sesmic waves move relitivly slowley through the asthenosphere and Under the thin oceanic plates the asthenosphere is usually much closer to the seafloor surface, and at mid-ocean ridge it rises to within a few kilometers of the ocean floor.
The Lithosphere
The lithosphere consists of lithospheric plates, otherwise known as the tectonic plates which drift slowly over millions of years. The rate of drift of these plates is comparable to the rate at which your fingernails grow. Over long periods of time, however, they can create mighty structures, such as the Himalayan Mountains in Tibet. Mt. Everest and the other Himalayas were formed when the tectonic plates underlying India forced its way upwards into Asia.
The Asthenosphere
The asthenosphere is a portion of the upper mantle between the lithosphere and is involved in plate tectonics movement. Sesmic waves move relitivly slowley through the asthenosphere and Under the thin oceanic plates the asthenosphere is usually much closer to the seafloor surface, and at mid-ocean ridge it rises to within a few kilometers of the ocean floor.
The Lithosphere
The lithosphere consists of lithospheric plates, otherwise known as the tectonic plates which drift slowly over millions of years. The rate of drift of these plates is comparable to the rate at which your fingernails grow. Over long periods of time, however, they can create mighty structures, such as the Himalayan Mountains in Tibet. Mt. Everest and the other Himalayas were formed when the tectonic plates underlying India forced its way upwards into Asia.