...causes the Earth’s movements. The theory of plate tectonics breaks down the exact functions of the lithosphere and the asthenosphere as it relates to how the Earth rotates. The outer layer of the mantle which is a rocky crust it what makes up the lithosphere plates. These lithospheric plates sit on a layer of Earth called the asthenosphere. The asthenosphere is a very hot weak layer that has a continuous movement. In plate tectonics there is a condition known as isostasy that works between the lithosphere, and the asthenosphere. What happens during this process is the lithosphere is basically floating on top of the asthenosphere, because the temperature is close to melting. One of the main influences of the Hawaii volcanoes is the fact that it sits on the Pacific plate the largest tectonic plate on the planet. As the sea floor spreads it causes the plate to continue to widen as well. That has the biggest impact of the growth of the Hawaiian Islands. Another key factor that not influences location, but the intensity is the changes in sea level. When the sea level began to change that made a decrease in the shorelines, so there was more land being submerged under water. The eruption of volcanoes in Hawaii is what influences an Earthquake. According to scientist Earthquakes are common after a volcano has erupted. The Hawaii was formed by a convergent margin of oceanic lithosphere plates. These plates join and on occasion can create a volcano. They can also be made in the middle...
Words: 958 - Pages: 4
...magnetism gets gradually weaker, showing that it is symmetrical on either side. The crust on either side of the ridge is symmetrical and gets gradually weaker and this means that crust is being formed in the ridge and pushed outwards, spreading out on either side. The fact that the magnetism is weaker away from the ridge means that the crust there is older. The second piece of evidence for Hess’s theory is the fact that crust found further away from the ocean ridge is proven to be much older than the crust closer to the ridge. This means that the there is new crust being formed in the ridges and it is spread out by the next crust that comes after it. Three locations that rifting has occurred is Africa, the Red Sea and the Atlantic. The lithosphere is the crust layer and upper part of the mantle of the structure of the Earth. The layer of the Earth’s structure that the plates float upon is the asthenosphere. This layer is made of semi-solid rock and is very hot and slowly flows beneath the plates. ...
Words: 624 - Pages: 3
...about 4.5 billion years ago, after the collapse of the super massive gaseous body. As time moved on, the earth cooled down and is still cooling, as of today. As a result of the cooling process, denser materials like iron and sulfur sank to the inside of the earth; whereas, lighter materials like silicates and water floated near the earth's surface. Coming to the topic of our discussion, our planet earth comprises several layers. Starting from the surface, there are four main layers; namely, the crust, the mantle, the outer core, and the inner core. The pressure and temperature increase tremendously when one goes from the outer layers to the inner layers. Let's take a look at each of them individually. The Crust The crust or the lithosphere is the outermost layer of the earth made up of silicate rock materials. It makes up only about one percent of the earth and is the thinnest layer in comparison to the remaining three layers. Most earthquakes occur in the crust, and the average recorded temperature is 870 °C. The thickness and the composition of the earth's crust vary in the land and the ocean. For example; the continental crust is about 32 kilometers thick and composed of lighter materials like granite, quartz, and feldspar. Whereas, the oceanic crust measures about 10 kilometers and is mostly made up of basalt. The Mantle The mantle, the largest layer of the earth, is made up of iron, aluminum, calcium, magnesium, silicone, and oxygen. In fact, most of the earth's...
Words: 950 - Pages: 4
...Geology Earthquakes I chose to do my assignment on earthquakes, because I have been through many growing up in California, and I have always wondered about them. There are many types of earthquakes. The most common are tectonic, which my paper will be about. There are also volcanic, collapse and explosion earthquakes. All earthquakes create waves that travel through the Earth's interior. An earthquake is the sudden shifting of the earth's natural means of releasing stress. When the shifting occurs, it creates vibrations, called seismic waves. The speed of seismic waves depends on the elasticity of the materials through which they are traveling. Rocks have elastic properties. When forces are applied to rocks, such as pulling, pushing, twisting, or compression, they change their shape. Rocks like other materials with elastic properties have an elastic limit,any additional force will deform the object's shape. The elasticity of a material is controlled by its density and stiffness. There are three types of waves that are created when stress is released as energy in earthquakes. Primary waves or P-waves, is the fastest, and the first detected by seismographs. They are able to move through both liquid and solid rock. P-waves are like sound waves; they are compressed and expand matter as they move through it. Secondary waves or S-waves, are the waves directly following the P-waves, they are transverse waves. As they move, S-waves cut the rock they travel through sideways...
Words: 1250 - Pages: 5
...Developed in the 1950’s through to the 1970’s, plate tectonics is the scientific theory first proposed and elaborated by scientist, Alfred Wegener in 1912. The theory explains that the lithosphere is divided up into multiple plates that are moving constantly. (Cloos, 2018). This theory is regularly being adapted and developed as it has been through the past 400 years by several scientists. At first scientists, including Wegener only compiled a small amount of evidence supporting this theory. However, scientists have now composed a more accurate and reliable hypothesis about the movement of all contents as well as the forming of several of the Earth’s geographical features, such as earthquakes, volcanos, tsunamis and mountain ranges. The scientific...
Words: 778 - Pages: 4
...THE STUCTURE OF THE EARTH The interior structure of the Earth is layered in spherical shells, like an onion. These layers can be defined by either their chemical or their rheological properties. Earth has an outer silicate solid crust, a highly viscous mantle, a liquid outer core that is much less viscous than the mantle, and a solid inner core. Scientific understanding of Earth's internal structure is based on observations of topography and bathymetry, observations of rock in outcrop, samples brought to the surface from greater depths by volcanic activity, analysis of the seismic waves that pass through Earth, measurements of the gravity field of Earth, and experiments with crystalline solids at pressures and temperatures characteristic of Earth's deep interior. ASSUMPTIONS: The force exerted by Earth's gravity can be used to calculate its mass, and by estimating the volume of the Earth, its average density can be calculated. Astronomers can also calculate Earth's mass from its orbit and effects on nearby planetary bodies. Observations of rocks, bodies of water and atmosphere allow estimation of the mass, volume and density of rocks to a certain depth, so the remaining mass must be in the deeper layers. Earth's radial density distribution according to the preliminary reference earth model (PREM). Earth's gravity according to the preliminary reference earth model (PREM). Comparison to approximations using constant and linear density for Earth's interior. Schematic view of...
Words: 1853 - Pages: 8
...Before we begin to explore the earth’s layers from core to atmosphere and the materials that it is composed of, we will need to look at the earth’s early stages of formation. Included in this is will be; what materials the earth is comprised of, as well as; how they arrived on the earth, and the resulting heat energy that is inherent within our earth. When the earth was still in its early stages of formation it was slowly accumulating mass from particles within the planetary rings that were attracted by the earth’s gravitational pull. These particles were metallic chunks; similar to iron meteorites, rocky chunks; similar to stony meteorites, and icy-gaseous chunks; similar to comets. As these particles collided with the earth it created stored heat energy through kinetic energy, we call this impact energy. With every impact the earth’s mass increased and the gravitational pull became stronger contracting in on itself which added more heat energy that we refer to as gravitational energy. Radioactive energy, or radioactivity, is when an unstable particle collides with the earth and break down to something stable and gives off heat energy. These three types of heat energy are inherent to the earth’s composition and are key when looking at the various layers that make up our earth. With all the inherent heat energy that the earth has, it causes the various materials that collide with earth to heat up as they are pulled toward the center of earth’s mass. This causes the...
Words: 591 - Pages: 3
...is the spatial analysis of all the physical elements and process systems that make up the environment: energy, air, water, weather, climate, landforms, soils, animals, plants, microorganisms, and Earth itself. 3. What are the inner core, outer core, mantle, asthenosphere, lithosphere, oceanic crust, and continental crust? o Inner core: solid iron well above the melting temperature of iron at the surface, but remains solid b/c tremendous pressure (combination of silicon, oxygen, sulfur) o Outer core: molten, metallic iron (fluid) with lighter densities than the inner core o Mantle: 80% of earth’s total volume, rich in oxides of iron and magnesium and silicates (FeO, MgO, and SiO2), • Lower mantle: denser, contain a mixture of iron, magnesium, and silicates, with some calcium and aluminum. • Upper mantle: a high-velocity zone just below the crust where seismic waves transmit through a rigid, cooler layer, divides into three fairly distinct layers: i. Upper mantle ii. Asthenosphere iii. Uppermost mantle o Asthenosphere: (plastic layer) contains pockets of increased heat from radioactive decay and is susceptible to slow convective currents in these hotter, less dense materials. o Lithosphere: approximately 45-70 km thick, and was made up of uppermost mantle and crust o Oceanic crust (denser): basalt, granular and high in silica, magnesium, and iron. o Continental crust (less in dense): essentially granite, it is crystalline and high in silica, aluminum, potassium...
Words: 335 - Pages: 2
...begin with the PLate Tectonic Theory which developed along with many other theories to describe the world’s processes and common natural occurrences. In the theory, it describes how the Earth’s lithosphere is divided up into many different plates that push and pull which affects the creating of many of the Earth’s features like mountains, ocean ridges, earthquakes, etc. The plates have different boundaries with one such being the divergent boundary which helps recycle and create a new lithosphere as we discovered in lab. It does this by splitting apart due to...
Words: 468 - Pages: 2
...Earth's crust and mantle Earth cutaway from core to exosphere The crust of the Earth is composed of a great variety of igneous, metamorphic, and sedimentary rocks. The crust is underlain by the mantle. The upper part of the mantle is composed mostly of peridotite, a rock denser than rocks common in the overlying crust. The boundary between the crust and mantle is conventionally placed at the Mohorovičić discontinuity, a boundary defined by a contrast in seismic velocity. The crust occupies less than 1% of Earth's volume. The oceanic crust of the sheet is different from its continental crust. The oceanic crust is 5 km (3 mi) to 10 km (6 mi) thick[1] and is composed primarily of basalt, diabase, and gabbro. The continental crust is typically from 30 km (20 mi) to 50 km (30 mi) thick and is mostly composed of slightly less dense rocks than those of the oceanic crust. Some of these less dense rocks, such as granite, are common in the continental crust but rare to absent in the oceanic crust. Both the continental and oceanic crust "float" on the mantle. Because the continental crust is thicker, it extends both above and below the oceanic crust. The slightly lighter density of felsic continental rock compared to basaltic ocean rock contributes to the higher relative elevation of the top of the continental crust. Because the top of the continental crust is above that of the oceanic, water runs off the continents and collects above the oceanic crust. The continental crust...
Words: 1549 - Pages: 7
...The structure of the earth The earth has three major parts-the land part or lithosphere, the water part or hydrosphere and the air part or atmostpere. The lithosphere is the surface on which you live . It is also the earth solid sphere consisting mainly of massive rocks. The massive rocks form large land masses called continent and small island groups . Different land form such as mountains,hills,valleys,plateaus and plains make up the lithosphere. The hydrosphere include all water forms such as oceans,seas,rivers,lakes,and groundwater found beneath the earth. Geologists or scientists who specialize on the history and composition of earth study carefully these two major parts of the earth. They study the different layers of the earth and what each layer is made of. You see only the surface of the earth – the oceans, seas, rivers, rocks, and soil. They cover the earth just like the thick peeling of the pomelo or orange fruit. When you cut open the pomelo, you see layers of pulp inside it. If the earth were cut open, you will see that it is made of three layers. They are the crust, matle and the core. The topmost layer of the earth is the crust which is made of solid rock. It is thicker under the continents; approximately between 11 to 35 kilometres. But under the oceans, it can be 5 to 12 kilometres thick only. At the lower boundary...
Words: 720 - Pages: 3
...Plate tectonics is a process that Withgott and Laposata (2012) say is of extraordinary importance to the planet. The intense heat from the inner core of Earth sends convection currents that flow in a loop in the mantle. This pushes the mantle’s soft rock upwards as it warms and downward as it cools. As this process takes place, it drags these large plates of lithosphere along the surface. The movement of these plates is known as plate tectonics (Withgott & Laposata, 2012). Earth’s surface is made up of roughly 15 major tectonic plates that fit together much like that of a puzzle, says Withgott and Laposata (2012). Withgott and Laposata (2012) also explain that these plates are estimated to move one to six inches per year. Though this is a slow movement, it has clearly influenced Earth’s climate and life’s...
Words: 488 - Pages: 2
...Reviewer in Science PLATE TECTONIC * There are two types of lithospheric plates: * Continental Lithosphere * Oceanic Lithosphere * The solid ground where you stand upon is called the continental crust, lighter them is oceanic crust * This type of crust has several deposits that vary in age forming the foundation of earth’s crust * Basement rock- the oldest foundation which is estimated to be four billion years age. It is mixture of granite and volcanic rocks * After the basement rock are PLATFORMS, younger layer of continental crust, made of sendimentary rocks. When platforms are connected with basement rocks, they are called Cratons * Cratons often survive the cycles of merging and rifting of continents * At the edges of cratons are the Continental Margins * When continental margins are moved by tectonic plates, natural landforms such as mountain ranges * Oceanic Crust- made of heavier basalt and gabbro rocks, younger than continental crust, older for this type is around 200 million years * In terms of thickness, oceanic crust measure only around 7km thick while continental crusts range from 10km to 70km thick * Location: Men will experience a more uniform condition due to the lack of significant typography and our landscape would be older VOLCANIC * These plates drift slowly over the mantle below, which is lubricated by a soft layer called ASTHESNOSPHERE * Volcano is a mountain that opens downward to a reservoir...
Words: 413 - Pages: 2
...Grade 4 Reading The earth is made up of several layers. Read the passage to learn more about them. Then answer questions 1 through 7. The Layers of the Earth by Doug Taylor If you were able to cut the earth in half you would see that it is not the same all the way through. The inside of the earth is made of several layers. Some of the layers are solid and some are liquid. Most of these layers are very hot. The center of the earth is called the inner core. Scientists think this part of the core is solid. It is probably made of metals like nickel and iron. The inner core is very hot. This deep inside the earth there is a lot of pressure. The pressure keeps the metals solid even though they are very hot. Scientists think the temperature in the core is about 7,200 degrees! Just past the inner core is the outer core. It is probably also made of metals. The metals of the outer core are melted into liquid. This layer is almost as hot as the inner core. The metals are able to melt in this layer because there is not as much pressure. The inner core and outer core together are about 3,400 kilometers thick! The next layer is called the mantle. The mantle is made of melted rocks called magma. The magma is a thick liquid. It flows like putty in most places. When magma erupts to the surface of the earth, it is called lava. The mantle is very thick and very hot. Scientists think the temperature of the mantle is about 5,400 degrees. The mantle is about...
Words: 851 - Pages: 4
...From the tallest mountains, all the way to the deepest ocean trenches, plate tectonics explains all the features & movements of earther’s surfaces in both the past & present. Plate tectonics, the theory that earth’s external shell is separated into numerous plates which glide over the rocky internal layer of the core called the mantle. The plates act like a rigid & hard shell compared to earth’s mantle. The lithosphere is what the strong outer layer is referred to as. Developed between the 1950s all the way through to the 1970s, plate tectonics is the up-to-date version of the theory first proposed in 1912 by the scientist Alfred Wegener, called continental drift. Alfred Wegener couldn’t explain how the continents move around the plant but...
Words: 1769 - Pages: 8
