Rock is a hard material, composed of different minerals & organic substance it forms a major part of the earth's crust.
Ex.-Marble,Coal,Quartz.
There are mainly three types of Rocks--
•Igneous rocks
•Sedimentary rocks
•Metamorphic rocks
1) Igneous Rocks--
Igneous's name came from Latin word "Ignis" which means "fire".
these rocks are formed by cooling & solidification of magma.
when volcanos erupt🌋 magma rise up & reach out to the earth's surface where it cools & form Igneous rocks at normal temperature.
when magma comes out to surface it looses its gases,called "Lava".
Ex-Granite,basalt.
•Approximately 90% of earth's crust is composed of igneous rocks.
2) Sedimentary Rocks--Sedimentary's name came from Latin word "Sedimentum" which means "settle down" .
these rocks are formed by the accumulation of sediments.
these sediments are eroded & isolated from pre-existing rocks & transported from one to other places through natural agencies such as wind,water.& deposited there & form Sedimentary rocks.
these rocks are found in layers.
•sediment means broken particals from the igneous rocks/pre-existing rocks driven by natural agencies.
Ex.-Limestone , sandstone , shale , coal.
3) Metamorphic Rocks-- Metamorphic's name came from Greek word "Metamorphose" means "change of form".
After many years,Igneous & Sedimentary rocks can change their form into Metamorphic rocks under high temperature, pressure & shearing stress.
Ex- Marble,slate.
--------------------------------------------------------
Thank you
Blogger - ANKIT KERKETTA
Kommentare