Constructive Forces, Folding, Faults, Magnitude and also Effect, volcanic Eruptions, Deposition of Sediment, devastating Forces, Weathering, Erosion

You might not establish it, yet the floor is transforming all the time. The planet is constantly working to build new land and to wear down the old.

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Sometimes transforms to the planet happen rapidly, but other changes can take millions of years!

Processes That change the EarthSlow ProcessesRapid Processes
ErosionVolcanic Eruptions
Deposition that SedimentLandslides

Constructive Forces

The procedures for building brand-new land are referred to as constructive forces. Three of the main constructive pressures are crustal deformation, volcano eruptions, and also deposition that sediment.

Crustal deformation occurs as soon as the form of floor (or crust) is readjusted or deformed. One of the main causes is activity of the Earth"s plates. Once the key collide or push toward each other, pressure builds. This can reason two points to happen. The rock deserve to either fold or fault.

Lava covering a road.


Imagine the remarkable force developed when 2 of the Earth"s bowl collide! over time, the press can cause rock to fold. As soon as that happens, the absent gets driven up, and also mountains are formed.

Usually, mountains type in ranges, or groups. Several of the best-known mountain ranges space the Himalayas, the Alps, and also the Andes. The Rocky mountains stretch all the means from brand-new Mexico to British Columbia, Canada. That"s around 3,000 mile (4,828 km).

View the Mt. Everest, Lhotse and also Nuptse from Kala Patthar.

Moraine Park - Rocky mountain National Park, Colorado.

The mountain Andreas Fault

The ideal known fault in north America is the mountain Andreas Fault. That runs about 800 mile (1,287 km) through California. It was responsible for one of the most famed earthquakes in history, referred to as the good San Francisco Earthquake that 1906. That earthquake and the fires it led to were among the best natural calamities ever to hit the unified States.


Sometimes, as soon as plates collide, the Earth"s crust can crack, or fracture. A error is formed. Follow me the crack, or fault line, the rock is being pushed together. Sooner or later, the pressure has to be released. When that happens, the an outcome is an earthquake.

A damaged building after one earthquake.

Magnitude and also Effect

1 come 3. Have the right to be recorded, yet rarely causes damage. Commonly not felt by humans.

3 come 6. Have the right to be felt by humans. Damages is usually minor. Some buildings can be affected.

6 come 9+. Have the right to cause good damage. One earthquake through a magnitude over 6 can cause damage because that 100 mile (160 km). Anything higher than 8 can cause severe damage over an area of hundreds of square miles. Earthquakes over 8 just happen around once a year.

Seismograph machine.

Dr. Charles Richter realized the the shocks resulted in by earthquakes can be measured. A device called a seismograph measures the shock, or seismic waves. The magnitude of one earthquake is measured indigenous 1 come 10, v 1 being the smallest and also 10 the largest.

Each number on the Richter scale represents a tenfold rise in the toughness of the earthquake. One earthquake v a magnitude of 2 is ten times stronger than an earthquake v a size of 1.

Active, Dormant, or Extinct?


A volcano that has actually erupted in recent history or the is meant to erupt again in the close to future.


A volcano that has not erupted because that a very long time, but may erupt in the future.


A volcano that scientists think will not erupt again.

Volcanic Eruptions

The sight of a hill pouring out smoke and red hot lava is among the many amazing in all of nature. A volcano is an opening in the Earth"s late that allows molten rock to escape. This molten rock, or lava, cools after that escapes and becomes igneous rock.

This eruption occurs as soon as pressure forces the release of lava indigenous a volcano.

Eruption in Piton de la Fournaise, Reunion Island.

Mount St. Helens venting steam.

Mount St. Helens native the north Ridge.

Mount St. Helens

It started with a series of small earthquakes. Lock shook mountain St. Helens in Washington State for several months. Vapor began to shoot indigenous the peak of the mountain. Then, on might 18, 1980, an earthquake through a size of 5.1 led to a fallen of the height of the mountain. Warm magma and also ash began gushing out.

Before it to be over, 230 square mile (596 sq km) of floor were extended in lava and also ash. Thousands and also thousands of acre were destroyed. Together with thousands of woodland animals and also millions the fish, 57 people lost your lives.

Deposition that Sediment

If you can cut into the surface of the Earth, you"d discover places wherein the rock is layered choose a birthday cake. These space layers the sedimentary rock, which form when rain, snow, ice, or wind lug rock particles. This particles space deposited in the water.

Over time, a procedure called lithification reasons the sediment come turn into sedimentary rock.

Sedimentary absent layers.

Coastline erosion.

Destructive Forces

So far, we"ve only looked at ways that soil is built up. In order for new rocks to it is in created, older ones should be destroyed.

Land is broken down through destructive forces. These pressures are at occupational all the time. Because they work-related slowly, that is sometimes tough to notification their effect. There is no them, however, new rock might never it is in formed. The two main devastating forces room weathering and erosion.


You can not think that something as harmless as the weather could failure rocks, however it does! Weathering is the breaking under of rocks v exposure to the atmosphere. There are two straightforward types the weathering: mechanical and chemical.

Mechanical weathering takes location when rocks are damaged apart. Because that example, water in rocks will freeze and thaw based upon air temperatures. This reasons the water to contract and also expand, i m sorry weakens the rock. End time, the rock division down.

Chemical weathering reasons rocks come weaken. When iron meets water the rusts. The exact same thing happens to the stole in a rock. When it rusts, or oxidizes, the rock gets weaker, and sooner or later it division down.

Iron has actually oxidized in this rock.


Once rocks begin to break down through weathering, erosion deserve to take over. Erosion is the procedure by which rock particles are moved. Water, wind, ice, and gravity have the right to all reason sediment come break far from rocks.

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Usually, particles relocate from higher places to reduced places. Heaviness can reason weathered rocks to fall down a mountainside. Rain deserve to wash it right into a river, wherein it move farther down still. The strength of the flow of the river can reason even an ext sediment to rest off along the riverbed.