The moho is not located at a uniform depth, but about 10 kilometers 6 miles below the seafloor and about 35 kilometers 22 miles beneath the surface of continents. A free powerpoint ppt presentation displayed as a flash slide show on id. Identify the elements that make up the core of the earth densities2. The earth has an outer silicate solid crust, a highly viscous. Earths interior crust, mantle, core discontinuities. Seismic waves and how we know earth s structure video transcript what i want to do in this video is really make some clarifications and go a little bit more in detail about the different layers of the earth. Crust mantle core our knowledge of these layers has come. Different layers of the earth its interior, structure and composition. Question the structure of earth s deep interior cannot be studied directly. Earth s layers the internal structure of the earth earth s layers kelvinsong, from wikimedia commons the interior of the earth is made up of several concentric layers of which the crust, the mantle, the outer core and the inner core are significant because of their unique physical and chemical properties. Crust, lithosphere, mantle, asthenosphere, core, seismic discontinuities, mohorovicic. The earths interior earth and planetary science university of. The interior of the earth, like that of the other terrestrial planets, is chemically divided into layers.
Atmosphere composition and structure notes the domain of air on the earth geography 9 atmosphere composition and structure earth is a unique planet because the life is found only on this planet. Maiya velazquez geosphere01 earth s interior the earth s interior helps us understand earthquakes, volcanoes, plate tectonics, etc. Understanding the basic structure of earth is very important to learn higher concepts well. Describe the process of convection within the earth s. Pdf the interior structure of the earth fabio catino. Seismic waves, shadow zone of pwaves and swaves pmf ias.
Earth and space science earth s interior page 3 of 3 content a. The interior structure of the earth is composed of three main layers. Structure of earths interior is fundamentally divided into three layers crust, mantle and core. The earths interior structure lecture 1 how do we know whats inside the earth. Seismology is providing a more sharply focused picture of the earth s internal structure that should lead to improved models of mantle dynamics.
Chapter 12 earths interior most of our knowledge of earth s interior comes from the study. The mantle is about 2,900 kilometers 1,802 miles thick, and makes up a whopping 84% of earth s total volume. Interior structure of the earth we have already seen how we can combine data with our knowledge of the basic parameters of the earth to determine that the earth is a stratified planet, that means, that the density of the earth increases as we go down to greater depths in the earth. In continuation to the geography notes which we provided earlier, today we will be covering a very important topic from the geography part of the general knowledge section on the topic important points about the interior structure of the earth a good number of questions from this topic are asked from this topic in every exam. Earth notes 17 earth s interior and its material 2. Important points about the interior structure of the earth. Meteors that at times reach the earth are an important source of information about the interior structure of the earth.
The innermost layer surrounding the earth s centre is called core, which is about 3500 kms in radius. Earths interior structure of the earth the structure of earth is in spherical form and is composed of four layers, three solid and one liquid which is in the form of molten metal, and is hot. Isaac newton gave a name to the concept of gravity and and discovered that gravity is influenced by density. Chemically, earth can be divided into the crust, upper mantle, lower mantle, outer core, and inner core. The mantle is the mostlysolid bulk of earth s interior. Thus, the post is very helpful for the upcoming ssc exams 2016. Therefore, the interior of earth can not be studied only by direct observations. In this lesson, anjali explains the internal structure of the earth, various sources of information through which earth s internal structure is known and the layers in which the earth is divided internally. The refraction or reflection of seismic waves is used for research into the structure of the earth s interior. Pdf earth is a very unique planet in the solar system. Seismic waves are waves of energy that travel through the earth s layers and are a result of earthquakes, volcanic eruptions, magma movement, large landslides and large humanmade explosions. Earth s diameter is approximately 12,756 km 7,500 miles. But geologists use seismic waves to determine the structure.
In this article geography section, we discuss the interior of the earth. Interior structure of the earth physical geography. But its properties are studied indirectly by deducing conclusions from the study of earthquake waves that propagate through the interior rocks and other such indirect means. Earth s interior is generally divided into three major layers. Earth s interior knowledge is limited temperature and pressure increase with depth. Lateral variations in seismic wave speeds have been documented in all major layers of the earth external to its core, with horizontal scale lengths ranging from 10 to 10 4 km. Internal structure of the earth 2 internal structure cont. The density of earth s surface layers is much less than the overall density of the planet, as calculated from the planets rotation. Meteorsmeteors are bits of interplanetary material falling through earth s atmosphere and heated to incandescence by friction. The composition and structure of earth physical geography. The interior has three main parts core mantle crust how the geosphere affects earth s spheres there are too different types of earth s. The hard, brittle crust extends from earth s surface to the socalled mohorovicic discontinuity, nicknamed the moho. Scientific understandi ding of the internal structure of the earth is based on.
Lecture notes and slides introduction to geology earth. Hence, this becomes yet another source of information about the interior of the earth. Interior structure of the earth notes the earth images. The core is composed mostly of iron fe and is so hot that the outer core is molten, with about 10% sulphur s.
Depth of mine 9 km only depth of magma chamber 64 km only analysis on the basis of seismic waves. Core is the most dense layer of the earth with its density. The interior of earth can be observed through direct evidence such as rock samples from mining, deep ocean drilling project, volcanic eruptions and indirect evidence such as seismic waves, meteorite investigation, gravitation force, magnetic field etc. The air has a special place among the conditions necessary for life.
It is given fact that the radius of earth is 6,370 km. Using gravity measurements in combination with earth s mass, scientists determined that the interior of the earth must be denser than the crust. These notes will also be useful for other competitive exams like banking po, ssc, state civil services exams and so on. The earth, the crust, the mantle, the core, continental crust, oceanic crust, upper mantle, lower mantle, inner core, outer core, lithosphere 865 km thick 2900 km thick 3480 km thick. Robertson abstract evidence on the structure and composition of the earth s interior comes from 1 observations of surface rocks, 2 geophysical data from earthquakes, flow of heat from the interior, the magnetic field, and gravity, 3 laboratory ex. The material and the structure observed in the meteors are similar to that of the earth. In interpreting earth motions from the geologic record, three needs seem paramount. Heaviest elements are placed at the core and lighter elements are at the surface. Structure of the earth earth s interior is divided into 3 layers that have very different properties. Studying the earths interior can help us to understand earthquakes, volcanoes, plate tectonics and more about the inner earths natural processes. Discuss and describe earth s interior the study of earth s surface and its interior falls under geology. The interior structure of the earth layers of the earth. Interior structure of the earth structure of the earth.
The mantle lies between earth s dense, superheated core and its thin outer layer, the crust. Average crustal abundance, density and seismic velocities of major crustal minerals. The earths interior a look at the layers of the inner earth. Earth is the densest planet in our solar system massvolume. If the surface layers are less dense than average, then the interior.
Structure of the interior of earth earth has a diameter of about 12,756 km 7,972 mi. Ppt structure of the earth powerpoint presentation. Earth and of the earths internal structure are also emphasized because the. Lower mantle definition position what are the layers of earth interior structure of the earth seismic evidence for internal earth interior of the earth geography study material notesthe earth s layers lesson 1 volcano world oregon statethe structure of earth earthquakes discovering geologyupsc geography interior of the earth neostencilinside the earth notesearth s layers crust. In this lesson bhanwar explains the internal structure of the earth, various sources of information through which earth s internal structure is known and the layers in which the earth. How do scientists know the structure of the earths interior.
Mechanically, it can be divided into lithosphere, asthenosphere, mesospheric mantle, outer core, and the inner core. These layers of the earth interact in ways that affect life on the earth. An example of a contemporary 1d velocity structure for the mantle and core the thin lowvelocity crust is not included is shown in figure 3, along with a density. Pdf structure and physical properties of the earths. The inner structure of the earth is described by the authors on the basis of systematic processing and evaluation of the traditional and newer theories and conceptions. Evidence on the structure and composition of the earths interior comes from 1 observations of surface rocks, 2 geophysical data from earthquakes, flow of. Find materials for this course in the pages linked along the left. Scientists know that the core is metal for a few reasons.
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