Their Express is made up of different types of rocks. In our previous video we had an overview of the three major classifications of rocks which are igneous, sedimentary, and metamorphic rocks
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Electromagnetic Radiation, Historical Design Practices
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Their Express is made up of different types of rocks. In our previous video we had an overview of the three major classifications of rocks which are igneous, sedimentary, and metamorphic rocks. The rocks which make up the maximum volume of the Earth's crust are the igneous rocks. Next to it is the metamorphic and the least when it comes to volume are the sedimentary rocks. Now what exactly is an igneous rock? Igneous Rock is derived from the Latin word igneous meaning fire. It is often called a magmatic rock. Even though it is formed through the cooling and solidification of magma or lava. As hot molten rock rises to the surface, it undergoes changes in temperature and pressure that causes it to cold solidify and crystallise. Same thing happens underneath the Earth's surface. When you think of a lava and magma, you probably picture this molten material integrator of a volcano. And that's what exactly we're talking about. But what I want you to keep in mind is that there is a difference between lava and magma. When it's deep inside the earth, under the surface, we call it magma. When these magma reaches the Earth's surface, it is known as lava. Now what is magma, magma is a molten in semi molten rock mixture found under the surface of the Earth. This mixture is usually made up of four parts, or hot liquid base called the melt minerals crystallise better melt solid rocks incorporated into the melt from the surrounding confines in the dissolved gases. Magma is extremely hot between 701,300 degrees Celsius. These heat makes magma a very fluid and dynamic substance able to create new landforms and engage physical and chemical transformations in a variety of different environments. So how long our form we studied that Earth is divided into three general layers. The core is the superheated centre. The mantle is the thick middle layer, and the crust is the top layer on which we live. Magma originates in the lower part of the Earth's crust and elaborate portion of the mantle. We studied that previously, it's the lithosphere. Most of the mantle and the crust are solid. So the presence of magma is crucial to understanding the geology and morphology of the mantle. differences in temperature, pressure and structural formations in the mantle and crust causes magma to form in different ways. So let's discuss them one by one. First is the compression melting. It involves the upward movement of Earth's mostly solid mantle, these hot material rises to an area of lower pressure through the process of convection. areas of lower pressure always have a lower melting point than areas of higher pressure. This reduction in overlying pressure or decompression enables the mantel rock to melt and form magma. That compression melting often occurs at divergent boundaries by tectonic plates separate. The lifting movement causes the buoyant magma below to rise and fill the space of lower pressure. Download 13.21 Kb. Share with your friends:
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