Question

D. Long Answer Type Questions.

1. How many types of rocks are there? Name and explain each with examples.

2.Which metals are used to produce nuclear energy?

3. Which metallic ore is most important for industries?

4. What do you understand by rock cycle? Explain with the help of a diagram.

5.What are the different uses of rocks?​

Answer 1

Answer:

5. used to produce fire

Used for construct buildings

used to make idols

Answer 2

Answer:

1 Igneous Rocks

Sedimentary Rocks

Metamorphic Rocks

Igneous Rock

Igneous rock is one of the three main rock types. Igneous rock is formed through the cooling and solidification of magma or lava. Igneous rock may form with or without crystallization, either below the surface as intrusive (plutonic) rocks or on the surface as extrusive (volcanic) rocks.Following are the two types of igneous rock:

Intrusive igneous rock: These rocks crystallize below the earth’s surface resulting in large crystals as the cooling takes place slowly. Diorite, granite, pegmatite are examples of intrusive igneous rocks.

Extrusive igneous rock: These rocks erupt onto the surface resulting in small crystals as the cooling takes place quickly. The cooling rate is for a few rocks is so quick that they form an amorphous glass. Basalt, tuff, pumice are examples of extrusive igneous rock

The sedimentary rocks are formed by the deposition and subsequent cementation of that material within bodies of water and at the surface of the earth. The process that causes various organic materials and minerals to settle in a place is termed as sedimentationTypes of Sedimentary Rock

Following are the three types of sedimentary rock:

Clastic sedimentary rocks: These rocks are formed from the mechanical weathering debris. Sandstone, siltstone are examples of clastic sedimentary rocks.

Chemical sedimentary rocks: These rocks are formed from the dissolved materials that precipitate from the solution. Iron ore, limestones are examples of chemical sedimentary rocks.

Organic sedimentary rocks: These rocks are formed from the accumulation of plant and animal debris. Coal, some dolomites are examples of organic sedimentary rocks

The metamorphic rocks make up a large part of the Earth’s crust and are classified by texture and by chemical and mineral assemblage. They may be formed simply by being deep beneath the Earth’s surface, subjected to high temperatures and the great pressure of the rock layers above it.

Types of Metamorphic Rock

Following are the two types of metamorphic rock:

Foliated metamorphic rocks: These rocks are produced by the exposure to heat and pressure which makes them appear layered. Phyllite, gneiss are examples of foliated metamorphic rocks.

Non-foliated metamorphic rocks: These rocks don’t have layers. Marble, quartzite are examples of non-foliated metamorphic rocks