2. Points and Terms to Remember
1.Seismic Waves: These waves are generated by an Earth quake.
2.Crust: The outer layer of the Solid rock are called crust.
3.Mantle: The thick Layer beneath the crust is called Mantle.
4.Tectonic Activities: The activities that effect the large scale
processes of the earth crust .
5.Rock:Hard Material That make up The earths crust.
6. Volcanic Rocks: Lava cools down on the earth surface.
7. Core: The interior Most Layer or Centre of the earth.
8. Mineral: Substance occurring in Nature with Definite chemical
composition.
3. Points and Terms to Remember
9. Igneous Rocks: Rocks which are formed by solidification of
magma are called igneous rocks
10. Sedimentary Rocks: The rocks which are made up of
sediments laid down usually on the sea-floor or lakes are known
as sedimentary rocks.
11.Metamorphic Rocks: The rocks which has change its original
form with disintegration .
12.Rock Cycle: Change of one rock into another type under
different condition.
13.Volcano: Magma from deep below forces its way up.
4. MCQ’s
1.________ is the uppermost layer of the earth
a. Core
b. Crust
c. Mantle
2.Volcanic Material deposits on the surface of the Earth is known as
a. Lava
b.Rock
c.Magma
3.The intensity of an earthquake id measured with the help of_______
a. seismograph
b. wind wave
c. Barometer
4. _________ Contains fossil flues.
a. Minerals
b. sedimentary rock
c. Metamorphic rock
5. MCQ’s
5.______is the main agent of chemical weathering.
a. Water
b. Frost
c. Wind
6. Moraines are the result of depositional work of
a. Wind
b. Glacier
c. River
6. •Do You Know?
1.The deepest mine in the world is in South Africa it
is about 4 kms deep. In search of oil engineers had
dug a hole about 6 kms deep.
2.To reach the centre of the earth(which is not
possible) you will have to dig a hole 6000 kms deep to
the ocean floor.
3.The crust formed only 0.5% of the volume of the
earth 16% consists of the mantle and 83% makes the
core.
4. The radius of the earth is 6371 kms
7. Word Origin
1. Igneous : Latin word ignis means Fire.
2. Sedimentary: Latin Word Sedimentum Means Settle down.
3. Metamorphic: Greek word Metamorphose means change of
form.
8. Glossary
1. Fossils: The Remains of the
dead plants and Animals Trapped
in Layers of rocks are called fossils.
9. Activity
What are the minerals most commonly used in the following
objects?
Kadhai- Iron
Tava/Pan-Iron And wood
10. Hammer- Wood and iron
Ornament - Gold and silver
Lamp- Aluminium
Bell- Brass
