Rock is a naturally occurring solid aggregate of one or more minerals or mineraloids. For example, the common rock, granite, is a combination of the quartz, feldspar and biotite minerals. The Earth's outer solid layer, the lithosphere, is made of rock.The scientific study of rocks is called petrology.
10 cool facts about rocks
1.The three types of rock found on the earth are sedimentary,Igneous and metamorphic rocks.
2.Molten rock below the earth's surface is called magma.When molten rock is expelled from a volcano,it's called Lava.
3.The earth's surface is made up of massive slabs of rock known as plates.The scientist called it as tectonic plates.When the plates move and collide,they can form mountain ranges and even cause earthquakes
4.Generally we have a thought that rocks are hard.But it is not true.Most rocks are hard but not all of them.Some rocks such as those made up of the mineral calcite,are soft enough to scratch with your fingernail.
5.The rock formed by the volcanic activity is called igneous rocks.Granite is a common igneous rocks.
6.A deep,narrow valley formed by erosion is called Canyons.They are often formed by water,ice or wind erosion.The grand canyons is one of the most famous canyons in the world.
8.The rocks found in flowing river is sedimentary rocks.They are formed when minerals and tiny pieces of eroded rocks are washed downstream.These sediments build up over time,and pressure turns the sediment into rock.
9.Some rocks sinks in water and some rocks floats on water.Pumice(a volcanic rock) forms when lava cools quickly and air bubbles form.The bubbles makes the rock less dense than water,so it floats.
10.A monolith is a geological feature consisting of a single massive stone or rock, such as some mountains, or a single large piece of rock placed as, or within, a monument or building.
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