ESTABLISHMENT OF EARTH PLATE THEORY

ESTABLISHMENT OF EARTH PLATE THEORY

Well my friends Science Lovers, this time we will discuss the theory of Plate Formation of the Earth, no need to linger just we get into the discussion of the article.

EARTH LAYER STRUCTURE

a. Atmosphere

The atmosphere is a collection of gas and air in the form of a thin layer surrounds or envelops the earth's surface. Likened to an orange, the earth is its contents while the orange peel is the atmosphere. 99% content of the atmosphere is at 30 km layer of bottoming. In the process occurs atmospheric weather and climate.

b. Lithosphere

The lithosphere is the layer below the earth's atmosphere. Lithos meaning stone and sfhere (sphaira) means sphere (layer). Lotosfer thus interpreted as a layer of earth that is hard, stiff and rigid with a thickness of approximately 0-70 km. The lithosphere is divided into two plates which are:

•     Plate Continent (0-10 km) with a layer containing sima.
•     Ocean plate (0-70 km) with a layer of bad luck.

c. Asthenosphere

Initerletak layer beneath the lithosphere with a thickness of 70-2900 km in the form of a solid material that behaves like a fluid. Or in other words, this layer is unstable so that, when affected by convection currents, it will move and move a layer on it such as earthquakes. The temperature can reach approximately 3000 ° C. The coat composition is divided into upper (upper mantle), the asthenosphere (part of the mantle), and coat the bottom. It can be said that part of the mantle asthenosphere.

d. Barisfer

Barisfer is the core layer of the earth. Which is composed of layers of nickel and iron. This layer is distinguished above 2, namely:

•     Outer Core is the earth's outer core with a thickness of 2900-4980 km. Composed of the elements iron and nickel that are liquid at a temperature of 3900 ° C.
• Inner Core is the inner core of the earth with a thickness of 4980-6370 km. Composed of nickel element which is solid even with a temperature of 4800 ° C due to the large pressure so that pressing and keeping the essence to remain in the middle.

THEORY OF PLATES FORMATION OF THE EARTH

1. Contraction and Expansion (contraction and expansion)

Earth shrinkage occurs due to the cooling process. This analogy is adopted from the event mengkerutnya dried apple peel. This theory may explain the depressed areas such as a row of volcanoes but not tapat explain hollows, crevices and valleys. This theory was first proposed by Descretes (1596-1650) and also in sukung by James Fund and Elie de Baumant.

Development of Earth occurred because the heating process. This theory gained after radioactivity known. He can explain how the continent can be destroyed and easily explain the formation of folds but can not explain the pressure areas.

2. Continental Drift (flotation continent)

At the beginning of the 20th century, scientists realized that they could not explain the structure of the Earth and processes with a single theory. Many scientists developed hypotheses to try and support the observation conflict. Alfred Wegner a meteorologist German study of ancient climates forward the theory of continental drift. Continental Drift hypothesis was put forward in 1910. Like most people, South America and Africa fit together like a jigsaw puzzle and attention.

He combines facts and fossil distribution to formulate a theory that the continents move on the surface of the earth. He argues that before 200 million years ago, all the continents formed a single landmass large and heavy that is named Pangea. Principle of this theory is the continent positioned on a plate or a rock, and they float along the surface of the earth every time. Wegner theoretical weakness and the reason is not accepted by gelogist is he argued that the continent was sliding above the seabed, but the seabed is not strong enough to sustain the continent.

3. Laurasia-Gondwana

Alexander Du Toit is a South African geologist. After his visit to South America, he became a supporter of the theory of Wegener. He mempubllikasikan Geological observations in A Comparison of South America with South Africa and then he developed his thinking in Our Wondering Contonents (1937). He declared the separation of pangea form two super continents that Laurasia (around the north pole) and Gondwana (around the south pole).

4. Paleomagnetism (ancient magnetic patterns rock)

During the second world war, geologist employed by the military named Harry Hass from Princeton University suggests research on the seabed. The purpose of this study was to understand the topography of the seabed, including measuring the depth of the seabed from the surface and find a hidden enemy submarine. Type of other studies using the magnetometer (to measure magnetic objects) placed behind the ships to detect submarines. This study also showed a magnetic anomaly under the sea, with a high magnetism and magnetism in the back of lower sea on the other.

This study suggests two important topography which backs the ocean and ocean trenches. Harry also stated that the continent does not move along the oceanic crust, but the continental and oceanic crust move together. If the new ocean crust and lithosphere is continuously formed on the back of seas, oceans will expand, unless there is a mechanism that destroys the ocean lithosphere. Benioff zones and ocean trenches proved that lithospheric mantle back to the ocean by breaking down in ocean trenches (subduction zone). Because the ocean plate is cold and brittle, it will rupture and re-mixed with matel and produce earthquakes are very deep.

In 1950 and 1960, research on the Earth's magnetic field and its changes over time (paleomagnetism) attest to the fact that the continents float latest. Conclusions of the concept of magnetic field are (1) the Earth has more than one pole change over time in the past. (2) different continents have moved relative to each other over geologic time. This study confirmed the hypothesis of the past and also confirmed the theory of Continental Drift.

5. Convection Current

The split continents and plate movement caused by the energy that moves. The energy comes from the asthenosphere convection currents within the earth. Convection currents is the transfer of heat energy to the fluid, caused by:

• The decay of radioactive elements
• Geometric Gradients
• Because of the attack foreign bodies
• The heat stored during the planet formation

6. Sea Floor Spreading

Plate movement that moves away from being caught by the researcher. This movement resulted in the formation of the ridge that extends in regions away. Vine, Matthews and morely gather important information and found that lenmpeng new ocean formed between the two plates apart. An intrusion of magma between the plates is causing the sea back. This theory is called Sea Floor Spreading and answer the biggest questions about the Continental Drift "How can the continent move above the ocean crust?" In fact, the continent moves along the ocean crust as part of the lithosphere. This phenomenon is due to convection heat flow from the Earth's upper mantle or asthenosphere.

7. Plate Tectonics

By combining the Sea Floor Spreading Continental Drift and global seismic information, the latest theory of plate tectonics was initiated by Mc. Kenzie and Robert Parker became the most plausible theory to explain the movement of the plates.

 

Plate tectonic theory is based on a simple model of the Earth. Dense lithosphere consists of oceanic crust and continental crust and is located in the upper mantle, and consists of several pieces of different sizes, called plates.

The plates are composed of oceanic crust with a thickness of 100 km and 250 km thick continental crust and float above the asthenosphere. When the continents and oceans can float because they are part of the large plates that float and move horizontally at the top of the asthenosphere. These plates are rigid (solid) with elastic ability, but the deformation appears along the boundary between the plates. And there are times when oceanic plates are infiltrated back into the mantle due to differences in thickness and density. Also the events of widening the plate due to convection currents. Intrusion events and this led to a widening of the boundaries between the plates. There are three types of plate boundaries are three Divergent Plate Boundary where plates move away from each other, Convergent Plate Boundary where plates move towards each other, and the latter Transform Plate Boundaries where the plates pushed berselisihan each other. Plate boundaries is what causes the tectonic and volcanic events that occurred on Earth.

Plate tectonics is a theory that was developed in the late 1960s, this theory explains how the process of movement and the formation of the outer plates of the Earth. This theory led to the revolution of human thinking about the Earth. Since the development of this theory, geologists have to reexamine virtually every aspect of geology. Plate tectonic theory has proved very useful because it can predict and explain geological events almost every aspect of what we see on Earth. Like the formation of mountains, earthquakes, and volcanoes.

In the development of the theory of plate tectonics, quite a lot of scientists who announced his research in the form of theories often we hear today.

Well buddy, this is the discussion of Science Lovers this time about the Theory of Plate Formation of Earth, may my friend all understand and useful knowledge.