The Earth 2

The Earth 2

By Miss Azka

The surface of the earth is covered by a layer of rock. This layer is called the earth's layer. Scientist who study rocks are called Geologists. Geologist study a number of different materials that they call rocks.

rocks, minerals and soil

Rocks

A rock is a solid collection of mineral grains that grow or become cemented together.

Rocks

Minerals is made of one chemical substance. In some rocks the minerals form small crystals. Example: Granite is a rock made from quite large crystals of 3 different minerals called quartz, feldspar and mica

Minerals

Soil is made of small particles of rock and mineral. It also contains the remains of plants, animal and waste products called humus.

Soils

Igneous rocks are formed from the solidification of magma, which is a hot molten or partially molten rock material.

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Igneous Rocks

Sedimentary rocks are types of rock that are formed by the accumulation or deposition of mineral or organic particles at Earth's surface, followed by cementation

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Sedimentary Rock

Metamorphic rocks form when rocks are subjected to high heat, high pressure, hot mineral-rich fluids or, more commonly, some combination of these factors. Conditions like these are found deep within the Earth or where tectonic plates meet

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Metamorphic Rock

Living organism can cause rocks to break apart. The growth of the plant's roots causes cracks and damaged to the rocks.

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Biotic Weathering

are formed from melted rock deep inside the Earth

Igneous

are formed from layers of sand, silt, dead plants, and animal skeletons

Sedimentary

formed from other rocks that are changed by heat and pressure underground

Metamorphic

Weatheringand Erosion

Rain, oxygen and acid are the example of chemical weathering agent. When they attack the limestone a chemical reaction takes place. It takes many years to notice the differences caused to limestone.

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Chemical Weathering

water gets into the spaces and cracks in rocks. When this water freezes it expands. This makes the cracks larger. When the water melts the larger cracks are left

Physical Weathering

Rock can be broken up into pieces by weathering. These pieces of rocks are called rock fragments. These fragments can be moved away by gravity, water and wind and called as erosion.

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Erosion

Deposition is the geological process in which sediments, soil and rocks are added to a landform or landmass. and build up and form sediments. The sediment at the bottom were deposited before the one on tops.

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Deposition and forming layers

Rocks break down into smaller pieces through weathering, it happens as wind and water rush over rocks. The rocks become smoother as rough and jagged edges break off.

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Abrasion

Multiple Choice

What is the difference between weathering and erosion?

• Erosion breaks rocks down, weathering carries sediment away

• Weathering breaks rock down and erosion carries the broken pieces away

• Erosion carries broken pieces away, and weathering builds the pieces back up into another land mass.

• Weathering carries broken pieces away, and erosion builds the pieces back up into another land mass.

Multiple Choice

Chemical weathering occurs more rapidly in a ________climate.

• mild

• dry

• cold

• hot

Multiple Choice

The image above depicts the effects of chemical weathering breaking down limestone. Which type of chemical weathering causes this reaction?

• acid rain

• exfoliation

• oxidation

• abrasion

• Fossils are formed from dead organisms that become part of a rock

• It tells us how some rocks were formed

• It tells us about life on earth millions of years ago​

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Fossil

• The fossil record tells us when different species of animals and plants first appeared on the earth

• It tells us how species of animals and plants have changed over million of years

• It tells us when species disappeared ​from the earth

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The fossil record

In 1912 a German scientist called Alfred Wegner suggested that million years ago all the land was one large continent. Over millions of years the land broke up and drifted apart. This idea is called continental drift.

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Continental Drfit

1. The shape of the continents fits together

2. The types of rocks on the different continents match up where they fit together

3. the fossils on the different continents match up where they fit together

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Evidence

Tectonic Plate

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This new theory called tectonic plate was developed in the 1960s. It states that the earth's surface is made up of large plates. The plates move slowly on the molten magma underneath them.

It is difficult to find rocks that are the same age as the earth because rocks are recycled and changed over and over again.

Scientist have found meteorites that are 4.5 billion years old. They think the earth is the same age as these meteorites.

How old is earth?