Classification of Rocks: 15+Types, Characteristics, and Formation

In This Article We Are Covers Classification Of Rocks

Geological Classification
Chemical Classification
physical Classification

Table of Contents

Geological Classification Of Rocks

A) Igneous Rock

At The Time Of Volcanic Eruption, Molten Mass Called As Magma Forcedly Comes Up On The Surface Of Earth At High Temperature. After Cooling Down This Molten Mass Become Solid Mass Which Called Igneous Rocks.

Classification Of Igneous Rock,

Igneous Rock Classification Based On Depth

1) Plutonic Rock

Plutonic Rocks As Non As Intrusive Rocks.

Rocks Formed By The Process Of Crystallization Of Molten Mass Non As Plutonic Rocks.

Magma At A Grate Depth More Than 35 m Or At Considerable Depth, Crystallization Is Slow And It Form Coarsely Grained Crystallization Structure.

Examples Of Plutonic Rocks- Granite, Pegmatite, Synite, Diabase, Gabbro Etc.

These Rocks Use As Building Stones And Act As A Masonry Material.

2) Hypabyssal Rock

Rock Formed By Process Of Crystallization Of Magma At Lower Depth About 30 m Or At Shallow Depth Non As Hypabyssal Rock.

Cooling Is Quick As Compared To Plutonic, Which Form Fine Grained Crystalline Structure.

Examples Of Hypabyssal Rock- Dolomite, Granophyre, Aplite Etc.

3) Volcanic Rock

Volcanic Rock Non As Extrusive Rocks.

Rocks Formed By Solidification Of Molten Mass At A Very Less Depth From The Surface Of Earth Or At Surface Of Earth Non As Volcanic Rocks.

Because Of Quick Cooling Extremely Fine Grained Crystalline Structure Formed.

Examples Of Volcanic Rock- Basalt, Andesite, Dacite Etc.

B) Sedimentary Rock

Because Of Weathering Action Such As Rain Water, Wind, Snow, And Sunrays. The Primary Or Principle Of Rocks Are Broken Up And Gradually Get Deposited At Bottom Of River, This Formation Of Rocks Called As Sedimentary Rock.

Classification Of Sedimentary Rock,

1) Clastic Rock Or Deposits

Rocks Formed By Destruction Of Igneous Rock Or Others Due To Vibration Of Temperature, Weathering Action And Corrosion. It Contains Fragments Of Pre-Existing Rocks.

Examples Of Clastic Rock- Clay, Limestone, Sand Stone, Sand Or Fine Aggregates, Laterite Etc.

2) Chemical Deposits Rock

Rocks Formed By Precipitation Of Mineral Matter Form Their Colloidal Solution In Water Non As Chemical Deposits.

Example Of Chemical Deposits Rock- Gypsum, Dolomite, Pumice Stone, Magnetite Etc.

3) Organic Deposit Rock

Rocks Formed By Organic Minerals Substance Depositions Non As Organic Deposit Rock.

Examples Of Organic Deposit Rocks- Limestone, Diatomite, Chalk, Shale, Shell-Lime Stone Etc.

C) Metamorphic Rocks

These Rocks Formed From Igneous And Sedimentary Rocks Under The Actions Or Influence Of Temperature, Pressure And Chemical Environment, The mineral Matter Re-Crystallizes Or Re-Alignment Of Minerals Gives The Higher Density To The Existing Rocks.

Examples Of Metamorphic Rocks- Marble, Slate, Schist, Gneiss, Quartzite Etc.

Chemical Classification Of Rocks

Chemical Classification Of Rocks,

A) Siliceous Rocks

Main Constituent Of Rock Is Silica Non As Siliceous Rock, Which Is Represented By “SiO₂“

These Rocks Are Hard, More Durable And Highly Resistance To Weathering Action.

Examples Of Siliceous Rocks- Granite, Gneiss, Quartzite, Sandstone, Synite, Trap, Gabbro Etc.

B) Argillaceous Rocks

Main Constituent Of Rock Is Clay Non As Argillaceous Rock, Which Is Represented By “Al₂O₃“

If Composed Of Alumina And Small Quantities Of Siliceous Materials, This Rocks Are Hard, Durable And Brittle.

Examples Of Argillaceous Rocks- Slate, Laterite And Schist Etc.

C) Calcareous Rock

Main Constituent Of Rock Is Lime Or Calcium Carbonate Non As Calcareous Rock, Which Is Represented By “CaO“

The Durability Of This Rock Depends On Texture, Constituents Of Atmosphere And Atmospheric Condition.

Examples Of Calcareous Rock- Marble, Limestone, Dolomite And Conglomerate Etc.

Physical Classification Of Rocks

Physical Classification Of Rocks,

A) Stratified Rocks

The Rocks Having Many Strata And Can Be Split Up Along Their Planes Into Thin Layers Non As Stratified Rocks.

These Are Dense And Durable, Sedimentary Rocks Belong To This Types.

Example Of Stratified Rocks- Marble, Limestone, Sand Stone, Slate And Laterite.

B) Unstratified Rocks

Rocks Not Having Any Strata But Containing Granular Crystalline Structure Non As Unstratified Rocks.

Igneous Rocks Belong To This Type.

Example Of Unstratified Rocks- Granite And Gneiss.

C) Foliated Rocks

The Rocks Having Foliated Or Bonded Structure And Can Split Up In One Definite Direction Non As Foliated Rocks.

Metamorphic Rocks Belong To This Category.

Example Of Foliated Rocks- Quartzite.

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Ketan Pattekar

Author & Editor Of This Blog.

Founder Of “KPSTRUCTURES”