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POWER exogenous (weathering, erosion, SEDIMENTATION)
Exogenous, or exogenous energy is energy which comes from outside the earth. Destructive or remodel the earth's surface that has been formed by endogenous power. Exogenous labor also led shapes the earth. Exogenous power can come from hydropower, wind, and the organisms that cause the process of weathering, erosion, denudation and sedimentation. Examples such as hills or cliffs that form the energy output of endogenous eroded by the wind, so as to change the shape of the earth's surface.

At sea level, the lithosphere appears to experience an erosion of the power that is exogenous to the weathering, erosion and transport, and sedimentation. For example, at sea level appears hill results tektonisme activity or volcanism. At first hill was destroyed by weathering power, then the ruins of the devastated power transported by water, wind, glaciers or by simply gravity of the earth. The results of the transport was then deposited, dumped in another part that eventually form the pile or carpet ruined assistance from rough to smooth.

Another example of an exogenous energy is coastal erosion. Every time the sea water into the coast and consequently soil and rocks eroded and carried away by water. Soil and rock that brought the water is then deposited and caused the beach to be shallow. In mountainous areas can also be found a rock which became smaller due to the wind.

In general, exogenous energy comes from three sources, namely:

    * The atmosphere, the change in temperature and wind.
    * Water may be the flow of water, the rain, the waves of the ocean, glaciers, and so on.
    * The organisms in the form of micro-organisms, plants, animals, and humans.

Vandalism of the earth form by exogenous energy in the form of weathering,

erosion (erosion) and deposition.

   1. 1. Weathering

Weathering of rocks is the destruction of a clot into droplets smaller even be crushed or dissolved in water. The process can be described as the process of weathering rock mass destruction through the destruction of media, such as:

   1. Sunshine
   2. Water
   3. Glacier
   4. chemical reaction
   5. activities of living things (organisms)

According to the weathering process can be classified into 3 types:

- Fiik or mechanical weathering

- Weathering organic

- Chemical weathering

   1. Physical and mechanical weathering.

Weathering mechanical (physical) is the process of destruction pengkikisan and boulders so smaller chunks, but do not change its chemistry. This process is caused by sunlight, temperature changes suddenly, and freezing water on a rock crevice.

The causes of mechanical weathering are:

1. The existence of a high temperature difference.

This event is especially true in the area of ​​temperate continental or temperate deserts in desert areas during the daytime temperatures can reach 50 Celsius. In the daytime high temperature or heat. Rock to expand, at night when the air cools, the rock shrinks. If it happens continuously can lead to rock breaks or cracks.

2. The freezing of water in the rocks

When water freezes it expands in volume. This development raises the pressure, because the pressure is batubatuan becomes damaged or broken broken. This weathering occurs in temperate zones with intense freezing.

3. Changing water into the salt crystal.

If ground water contains salt, then in the afternoon the water menguapdan salt will crystallize. Salt crystal salt is very sharp and can damage the rock of the surrounding mountains, rocks, especially in coastal areas.

Organic 2.Pelapukan

The reason is that the animal organism danmanusia plants, animals can do weathering such as earthworms, insects. Dibatu-rock coastal areas often have holes made by animals. The effect caused by the growing plant can be mechanical or chemical. Influence the mechanical properties of the roots of plants growing in the soil which can damage the surrounding soil. The influence of chemical substances in the form of acid released by akarakar suck salt dietary fiber foods. Acid rock that is damaging salts are readily absorbed by the roots. Humans also play a role in weathering through activity logging, construction and mining.

3.Pelapukan chemical

On this rock weathering rocks undergo chemical changes which tend to be flaking. Apparent chemical weathering occurs in limestone mountains (karst). Weathering takes place with rocks and water temperatures. Water that contains CO2 (carbonic acid substances) can easily dissolve limestone (CACO2). This event is a solution and can cause symptoms of karst. In Indonesia, the case is weathering chemical weathering. This is because in Indonasia much rain. Rainwater which facilitate the occurrence of chemical weathering.

Symptoms or form - a form of nature that occur in karst regions are:

a. Dolina

Dolina is the hole hole berbanuk funnel. Dolina may occur due to erosion (dissolution) or because of debris. Dolina found in almost all parts of pegununga limestone in the southern part of Java, which is in the mountains a thousand.

b. Caves and rivers in the Land

In the original limestone there are gaps or cracks. Cracks will be even bigger and form caves or holes, due to the influence larutan.Jika holes connected, will form rivers in the ground.

c. Cone is a cone limestone stalactites hanging on the roof of the cave. Formed from thick limestone due to air in the cave. Stalagmite is a cone-cone stand at the base of limestone caves. Contohnnya stalactite and stalagmite in the cave and the cave Gong tabunan in Pacitan, East Java and Cave jatijajar in Kebumen, Central Java.

2. Erosion

Such as weathering erosion is power decomposer (pengkikisan). But what distinguishes erosion by weathering is erosion pengkikisan media is moving, such as river water, wind, ocean waves, or glaciers. Erosion is distinguished by the type of power perombaknya namely: water erosion, erosion waves (abarasi / marine erosion), wind erosion (deflation), glacier erosion (glacial) ', Erosion Due to gravity.

   1. Water Erosion

Erosion by water is erosion caused by water or excessive rainfall hujan.Jika level such that the soil can not absorb rain water, and there was a puddle of water flowing kencang.Aliran This often leads to severe erosion because it can erode the surface layer land in its path, especially on the bare ground.

    Stages in the Water Erosion

Process pengkikisan by flowing water occurs in four different levels according to soil degradation or erosion of rock, as follows.

   1. Splash erosion, which is a process pengkikisan by rain that falls to earth.
   2. Sheet erosion, which is a process pengkikisan the topsoil so that fertility is reduced. Pengkikisan sheet is characterized by:

    * Color of the water flowing brown
    * Water colors become paler eroded
    * Reduced soil fertility

   3. Gully erosion, is a continuation of sheet erosion. Characteristic erosion gully is a deep furrows in the ground water flow sebsgai place
   4. Gully erosion, is the formation of gullies or valleys due pengkikisan water flow. If erosion continues trench, then the area of ​​degraded land can be expanded, and at this level already broken ground.

    * The shape of Earth's Surface Due to Erosion

Pengkikisan by the water can lead to:

   1. The river bank in
   2. The steep valley
   3. Cave formation

2. Erosion by the sea water (abrasion)

Erosion by the sea water is erosion on the beach by the ocean waves beating occurred on a continuous - going to the beach wall. Landscape erosion caused by sea water, such as cliff (steep cliffs), notch (notch), a cave on the coast, wave cut platform (wave cut backs), headlands and bays. Cliff formed by the waves on the shore rocks weaken. In the first wave of meretakan rocks on the beach. Finally, the cracks getting bigger and deeper notch shape will form the cave. Due to constantly buffeted gelobang lead roof of the cave collapsed and formed the cliff and wave cut playform.

Headland is land that juts into the sea, while the bay is overhanging the sea inland. The beach has rock types alternate between resistant and resistant rock. In the resistant rock will not easily eroded, while the resistant rock is difficult to erode. As a result, the resistance will not rock that juts into the bay formed land-resistant rock formed at headlands jutting into the sea.

    * Due to Abrasion

Abrasion usually occurs on the coast, forming:

   1. The walls of the steep coast
   2. Recesses (grooves on the wall of the cliff)
   3. Cave beach
   4. Stone screen
   5. Cliff
   6. Notch
   7. Cave on the beach

   1. BY WIND EROSION (decorating)

Erosion by wind erosion is caused by wind. Winds blowing continuously in the arid region can move fine particles of rock in the area to form a formation, such as sand dunes in the desert or beach.

Erosion by wind (wind erosion typically occurs in deserts) may result in:

   1. Mushroom stone
   2. Canyon

   1. Erosion by ice / glacier

Erosion by a glacier erosion by glaciers (ice sheets) in mountainous regions. This erosion occurred in an area that has four seasons. In the spring, erosion by glaciers that slid down the valley. Akkibatnya slope becomes steeper. Examples of landscape erosion caused by glaciers is a coastal fjord, which is a beach with a winding serpentine wall.

   1. Erosion Due to Gravity

Rock or sediment that moves on a slope erosion processes caused by gravity. Erosion will take place very quickly which can cause landslides.

3. Sedimentation (precipitation)

Sedimentation is the deposition of rock material events that have been transported by water or wind power.

The process of sedimentation or precipitation based energy transporter:
a. Deposition of water (aquatic)

a) Meander

Meander is a winding river - winding formed due to precipitation. The process of winding rivers keloknya starting hulu.Pada upstream river section, a small volume of water and energy are formed too small. As a result, the river began to avoid obstacles and find the easiest route impassable. Meanwhile, on the upstream precipitation has not occurred. In the center, a flat area ranging from slow water flow and form meanders. The process occurs at the edges Sungi meanders, both inside and outside edge. At the river will quickly aliranya erosion by the river while the slow flow precipitation will occur. When that takes place continuously will form meanders.

 Meander is usually formed at the lower reaches of the river, where deposition occurs pengikisandan respectively. Yangterjadi deposition process on a continuous basis will cause the curve of the river cut off and separated from the river, so that form oxbow lake.

b) Delta

When the flow of water near the estuary, such as a lake or ocean aliranya then speed becomes slow. As a result, sediment deposition terkadi by river water. The sand will be deposited while the clay and mud will still be transported by water flow. After so long, it forms a layer - the layer of sediment. Finally Lapian sediments forming the vast plains on the river near its mouth and form a delta. Delta formation meet several requirements. First, the sediment carried by the river had a lot when going in the sea or a lake. Second, the current along the length of the beach is not too strong. Third, the beach should be shallow. Examples of this landscape is the Musi River delta, Kapuas, and Kali Brantas.

c) flood plains and natural levees

In the event of rain, the water volume increases rapidly. As a result, flooding and overflow of water up to the edge of the river. At low tide, materials carried by the river would terendapkan river. As a result, formed a river plains. The emergence of material that is not smooth (rough) is located on the river bank. As a result, the river is higher than the flood plain is formed. Landscape are called natural levees.

b. Deposition of sea water (marine sediments)

a) Slip and Tombolo

The rocks that deposition by sea water called sediment marine.Pengendapan by seawater due to the waves. Landscape alamhasil deposition by sea water, coastal Among other things, spit, Tombolo, danpenghalang pantai.Pesisir a deposition areas along the coast. Usually consists of sand material. The size and composition of the material on the beach a variation depending on changing weather conditions, wind direction, and ocean currents. Shore currents transport material there along the coast. If terjad change of direction, the beach will remain current material transport material into the sea. when material into the sea, there is deposition of material. After all this time, there is accumulation of material on the surface of the sea. Called the accumulation of material that spit. If the current continues beaches, spit will become longer. Sometimes spit formed through the bay and set up a barrier beach (barrier beach).

If there pulam around the spit, spit usually end up connected to the mainland, thus forming Tombolo.

c. Wind Deposition (sediment Aeolis)

Sediment yield of sediment deposition by wind called Aeolis. Landscape by wind deposition results can be sand dunes (sand dune). Coastal dunes can occur in coastal areas and the desert. Sandbanks occur if there is a fair amount of sand accumulation and strong winds. The wind transports sand and mengedapkan tu sua place gradually forming a heap of sand called sand dunes.

 d. The deposition by glaciers

Sediment deposition results by glaciers called glacial sediments. Landscape results deposition by glaciers is the original form of a V-shaped valley into U. By the time spring arrives, erosion by glaciers that slid down the valley. Rock or soil erosion results also settle down the slope and weak. As a result, the original V-shaped valley into a U-shaped

The positive impact of exogenous force include:

1. Bring up the habitat.

2. Expanding land on earth.

3. Bring together the mineral to the surface of the earth.

Nevertheless exogenous force also has negative impacts that could harm humans. Negative impacts include:

   1. Soil fertility can be reduced (the effect of erosion).
   2. The results of the precipitated erosion (sedimentation) in estuaries result in silting of the river.
   3. Abrasion can eliminate lost coastline hit