Luokat: Kaikki - sedimentary - igneous - metamorphic - fossils

jonka NAJLAA' BT JUNAIDEE 3 vuotta sitten

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TYPES AND CHARACTERISTIC OF ROCKS

Rocks are categorized into three primary types based on their formation processes: igneous, metamorphic, and sedimentary. Igneous rocks form from the cooling and solidification of magma or lava.

TYPES AND CHARACTERISTIC OF ROCKS

TYPES AND CHARACTERISTIC OF ROCKS

SEDIMENTARY ROCKS

Examples of sedimentary rocks
Coal
Gypsum
Conglomerate
Shale
Sandstone
Limestone
Softer and more brittle than igneous rocks
Have dull surfaces
Have no crystallised structures
Often contain fossils
have layers
The fragments of sediments are transported by streams and deposited with mud,silt,sand,animal shells and fossils on the seabed
Are weathered and eroded by wind,rain,waves,ice and heat from the Sun to form fragments of sediments

METAMORPHIC ROCKS

Examples of metamorphic rocks
gneiss
marble
Some have no layers like marble
Some have layers like gneiss and slate
Harder and denser than their parent rocks
Some contain crystal such as schist
Shiny
Are formed either igneous rocks or sedimentary rocks that undergo chemical changes due to very high pressure and temperature

IGNEOUS ROCKS

Example of igneous
Characteristic
contain no fossils
have no layers
have crystallised structures
shiny
hard
Magma that is trapped deeper in the crust will cool slowly and crystallise into coarse-grained igneous rocks such as
diorite
gabro
granite
Lava cools rapidly and crystallises into fine-grained such as:
obsidian
pumice
basalt
During volcanic eruptions,magma spurts out of the Earth's surface as lava