Did you know that the earth we live on has been continuously changing for millions of years? Well, the shape of the land, mountains, and even the seabed was not always as it is now. So, the slow but sure movement of the earth's plates has formed a beautiful and amazing natural feature. This is what is studied in the branches of geology, namely the science that explains how the earth can change over time. And the natural beauty that we see, such as mountains, valleys, islands, is the result of a long process called landscape morphology. You certainly still remember when you studied the branches of science in 7th grade. One of them was geology, which discussed the earth and all its changes. Well, did you know that most of the beautiful views we see, such as mountains, beaches and valleys, are the result of natural processes that have been taking place for millions of years. Well, these forms of the earth's surface are called landform morphology. Come on, let's observe some examples of natural landscapes in Indonesia. Landscapes are naturally formed forms of the earth's surface, such as mountains, rivers, beaches and valleys. Well, this formation process can be caused by the movement of the earth's plates, erosion or volcanic activity such as weathering and so on. Indonesia is an archipelagic country that has a very diverse and beautiful natural landscape . Starting from the Jayawijaya mountains in Papua, Lake Toba in Sumatra to a row of exotic beaches in Bali and Lombok. Well, because the diversity of this natural landscape is one of the natural treasures that we should protect and be proud of. Well, changes in the landscape occur due to geological forces, namely the forces that form the earth's surface, which are divided into two. First, there are exogenous from outside the earth and endogenous, namely from within the earth. In this chapter we will explore how forces from within the Earth such as tectonism, volcanism, and geology shape the Earth's structure and create its incredible natural wonders . There are three characteristics that make up the layers of the earth. First there is the earth's crust, then there is the earth's mantle, and there is the outer core and the inner core. Have you ever seen a boiled egg? It turns out that the structure of the earth is similar to a boiled egg. Oh, how is that possible? Well, the egg shell represents the earth's crust, which is the thin outermost part. Then the egg white is like the earth's mantle. The second part is a bit thicker and the egg yolk resembles the earth's core. Each layer has unique characteristics to compose and shape the earth where we live. Did you know that the outermost part of the earth where we stand is called the earth's crust. Well, even though it is the thinnest layer, the earth's crust contains many important elements and valuable minerals. This crust is also where all life takes place, both on land and on the seabed. Come on, let's look more deeply into the characteristics of this layer of the earth . Furthermore, behind the earth's crust that we are standing on, there is a thick layer called the earth's mantle. Well, this layer is the thickest and heaviest, stretching thousands of kilometers deep. Even though it is made of solid rock, the high heat makes it plastic and able to move. Well, this movement also influences the earth's activities such as earthquakes and volcanoes. The earth's core consists of two parts, namely the inner core and the outer core. Have you ever imagined the deepest part of the earth which is very hot and liquid? Well, that's where the Earth's outer core is located , which is a unique layer that is different from the crust and mantle because it is a thick liquid. not water, but hot metals such as iron, nickel which continue to move into it. Well, this fluid movement even plays an important role in creating the Earth's magnetic field that protects life on the surface. Imagine being at the center of the earth, a place with incredibly hot temperatures reaching 7,000 degrees Celsius and pressure so great that even liquid metal turns into solid. Well, this is the inner core of the earth. The innermost layer is composed of iron, nickel, solids, and other elements such as sulfur and carbon. Even though it is hotter than the surface of the sun, the extreme pressure keeps it solid, making this layer the center of strength and stability of the Earth. The large or moving parts are parts called tectonic plates. that is, these plates are like giant puzzle pieces that continue to move very slowly on the top layer of the Earth's mantle. Well, this movement is what causes the formation of mountains, earthquakes, and even continents shifting positions over millions of years. Well, understanding plate tectonics helps us understand how the Earth continues to change over time. Come on, let's take a look. The earth's plates that we carry are always moving. Well, this movement is called tectonism, namely the movement of the earth's plates. Different from volcanism, which is related to volcanic activity . So, tectonism is part of endogenous forces, namely forces that originate from within the earth. Now let's look at the continents in the world. Well, this is what causes or is the result of tectonism, namely the movement of the earth's plates so that it breaks up various continents. In addition, tectonism is a horizontal and vertical movement that causes changes in the shape of the earth's surface. This movement in tectonism is called tectonic movement or this tectonic movement can affect the earth's surface because this movement causes cracks, folds, curves and faults. There are three movements of the plates. The first is divergent movement or moving away from each other. Divergent plate boundaries occur when two Earth plates move away from each other. As a result, magma from within the earth rises to the surface and forms a new layer of the earth's crust. For example, the formation of the mid-Atlantic right, namely mountains or seabed in the Atlantic Ocean. The second is the plate boundary from convergent or colliding with each other . So this convergent plate boundary occurs when two plates collide, causing one plate to sink into the other plate. This movement can cause very strong earthquakes such as the earthquake and tsunami that occurred in Aceh on December 26, 2004. The third is the transform plate boundary . or passing each other . Transform movement occurs when two plates rub against each other horizontally and in opposite directions. This friction generates energy that can trigger shallow earthquakes. For example, the San Andreas fault in California, United States and is 1300 km long. Have you ever felt the ground shake suddenly? That's what is called an earthquake. Earthquakes are a natural event that can occur anytime and anywhere. Especially in regions like Indonesia which run along the ring of fire. So, in this 8th grade science lesson, we will learn how earthquakes occur, what causes them, and how they impact life. What is a seismicity? Seismicity is a vibration that occurs due to the release of energy from within the earth. These vibrations occur due to the accumulation of energy between the continental and oceanic plates. If the energy is large, an earthquake will occur. So seismic is the scientific term for vibration. While an earthquake is an event that we feel. Types of earthquakes based on the process of occurrence. Well, it is divided into three. There are tectonic earthquakes, then volcanic earthquakes, and series earthquakes. It can be seen as follows. The strength of an earthquake can be measured using a tool called a seismograph or the unit of strength is called the rister scale. So, you can check the size of the earthquake strength or magnitude if measured using a rister scale. Well, let's see. earthquake categories based on earthquake strength. If it is 3 to 3.9 it means minor. Well, even if it's more than 8 it's very big. It can be determined using the rister scale in the following table . Volcanoes often sound scary because of their very powerful eruptions. However, did you know that volcanoes also bring many benefits to life? In this 8th grade science lesson, you will learn about volcanoes, what they look like, and their impacts on everyday life. The occurrence of volcanoes is based on the earth's plates. Well, the formation of the result of the movement of tectonic plates that form the earth's crust has three processes. The first is the subduction zone or plate collision, the second is divergence, which is the spreading of the plates. Then the third is from hotspots or hot spots, namely magma rising from hot spots in the Earth's mantle and forming volcanoes in the middle of the plates. The following are the benefits of volcanoes which can be seen as follows. Thank you in advance. Don't forget to follow, subscribe, and bye bye.