Unlike in the earth's surface, rocks are buried deep in the earth's core is affected by pressure and temperature are very high. Consequently, although the rocks in the earth's core in the form of solids, they can flow like a glacier moving slowly down the slope. At the beginning of our planet's history, meeting materials in the form of iron and nickel precipitate and form the core of the earth. The core is the most concentrated, with a radius of more than 2,900 miles. There are two core layers: inner and outer core. At the core there is a layer above the mantle sheath, which consists of silicate rocks (compounds of silicon and oxygen) are relatively tight. Oceanic crust and continental crust floats on top of these layers like a puddle of oil on the water surface.

note the picture above, dense and solid rock is derived from the Earth's mantle and containing the green mineral olivine. He brought to the surface when a volcano eruption in Canary Islands. Certain geological processes, such as volcanic eruptions, usually can give important clues about the structure of the earth.

Iron is the largest constituent of the earth element. The metal is centered on the Earth's core. Magnesium silicate compounds, which contain magnesium, silicon, and oxygen, the principal constituent of the coat layer. Most of these constituent elements have been created in space since millions of years ago.

IN THE CORE
Condition of the earth's core was unthinkable. The pressure is so large and its temperature is supposedly more than 3.0000C. Geologists can measure the temperature in the layer between the inner and outer core. The core is composed of iron mixed with some foreign elements. Scientists have made a replica model of the earth's core. The pressure was reached almost 4.0000C. Incandescent iron circulating in the outer core slowly. Electric current inside a magnetic field of the earth whose scope is penetrated far into space. The magnetic field form a kind of magnetic blanket around the planet, deflecting the electrically charged particles from the sun, and protect us from solar radiation. The magnetic field generated at the core of the earth is constantly changing with the variation expected very large, although the variation is always tempered by the mantle. However, every 100,000 years, the variation of the magnetic field so much that can reverse the direction of the field.

note the picture above, seismic waves spread following a seismic event in eastern Africa. Geologists can expect the ins and outs of the planet's structure by noting the time arrived at the station-wave seismic monitoring stations around the world. Pressure waves can penetrate the red outer core is molten. Transverse wave (blue) can only penetrate a strainer mantle and crust are solid.

Earth's magnetic field to form the skins sheath called the magnetosphere, which stretched far above the planet's surface and reach space. The wind of charged particles that waft out of the sun pushed the magnetosphere to form the tail currents, like a comet tail.

Shape the flow of the magnetic field as if it shows that in the earth there is a giant magnet. Strong magnetic lines of force is actually the result of electric currents circulating in the outer core is molten.

CONTENTS OF PLANET EARTH
Heat generated by the process of planet formation up to now are still released into the surface. The heat continues to be discarded from the interior of the earth. The core part in getting freezes and radioactive elements decay. The heat would escape blocked by layers of rock, which is a strong insulator. So that heat can escape, rocky mantle that surrounds the inner core must be circulating. Delivered piping hot to the top along with the hot mantle rock that moves up. Near the surface, in layers of brittle rocks, the movement of rock layers causing an earthquake occurs. Seismologists, or scientists who study earthquakes, operates a network of earthquake monitoring stations. The timing of the arrival of seismic waves (seismic) in some stations are far apart, a sophisticated computer can make a picture of the inside of the interior) of the earth.

ACTIVITIES IN THE BODY OF THE EARTH
From the observation, it is known that there is a 'chimney' of the Earth's mantle that directs the hot material rises to the surface, then emerged as the crater of the volcano. The rate of seismic waves slow down when passing through the material is hot and soft. This contrasts with a layer of hard rock and cool-down into the mantle, where the cold ocean crust disappears beneath the continental shelf. Based on the analysis of seismic data, geologists can find a transitional limit of about 670km below the earth's surface, exactly in the mantle. The rock moving down apparently gathered in the layer. It makes several geologists proposed the theory that the whole mantle circulation does not mix in one but in two layers of rock circulation. Recent seismic data analysis shows there is another thin layer of base coat, with a few tens of kilometers thick. These layers are not continuous and not whole, but rather more like scattered giant continental plates under coat layer. Plates were allegedly formed when the silicate rocks in the mantle mixed with material from the core of a rich iron content. However, other experts argue that these plates are the ancient ocean over. After moving down to the bottom layer of the upper mantle, ancient oceanic crust until cold pressed into a layer of rock that is very tight. Then, this layer is a layer of thickness 670 km and even more deeply immersed. These layers are continuing to spread at the base of the mantle. When the core of the earth gradually heats the layers of rock that meeting, this layer is once again moving up to form new ocean crust.

READING GUIDE
Mainland is compressed by the pressure of the ice during the last ice age, along with the influence of gravity the moon (tidal phenomena), gradually slowing the rate of rotation of the earth. As a result, the length of day or night slightly increased. Other changes also took place, although measurable is much smaller, at only a fraction of a billionth of one second. This allegedly caused by changes in atmospheric pressure on the lines of the mountains. Besides urging the circulation of the outer core of the back hills, which rests on the base coat is similar upside of the mountain. Change in length of day and night an indication of the circulation in the core symptoms of the earth, besides giving clues about the various other important geological processes in the earth.