Website Earth Science, Geography, Geology, Engineering Geology, Oceanography, Meteorology, Astrononomy, Human Geography, Environmental Sciences, mapping, map usa What are Igneous rocks? different types of Igneous Rocks. - Geo Studies Organization

What are Igneous rocks? different types of Igneous Rocks.

There are three basic types of rocks. The igneous rocks, the metamorphic, and the sedimentary rocks. This classification has been made by earth scientists on the basis of their formation, properties, and composition. Read this classification in detail. Types of rocks.

Igneous Rocks:

The term igneous has been derived from the Latin word “Ignis”, which means fire. Thus the name denotes that the rocks, which originates through fire. Scientifically speaking, these rocks were formed as a result of the cooling of molten magma erupted in the form of Lava, either inside the crust or on the surface. According to the definition of Blij,

“Magma is not only a complex melt of many minerals, it also means gases including water vapor. It is a surging, swelling mass that pushes outward and upward. Sometimes facing itself into and though existing layers of rocks in the crust. If its upward thrust ceases before it reaches the surface, the resulting rock formed from the cooled magma are called intrusive igneous rocks. If it penetrates all the way to the surface and spills out as lava or ash, the rocks formed from these materials are called extrusive igneous rocks.”

Igneous Rock

Types of Igneous Rocks:

(1). Types on the basis of Location:

There are three types of the Igneous Rocks which are categorized on the basis of the their mode of formation:

  • Plutonic Rocks:

These rocks are found at great depths because the molten magma cools down at places situated deep in Earth. The plutonic rocks are crystalline such as granite. The crystals of these rocks are large in size.

  • Dyke Rocks:

These rocks are formed in dykes of vertical wall-like structure because the molten material gushing from the interior of Earth does not reach the surface of Earth though volcano’s mouth. The structure of these rocks is semi- crystalline.

  • Volcanic Rocks (Lava):

The rocks which are formed as result of the volcanic eruptions are called volcanic rocks. These are glassy and belong to the extrusive category of igneous rocks.

(2). Types of igneous rocks on the basis of Elements:

The rocks are composed of different elements. These are divided into four types on the basis of the proportion of element:

 Alkali Rocks:

These are composed mostly of the alkalis.

Silicon Rocks:

In these rocks, in the percentage of silicon is more than the percentage of irons, magnesium and lime. e.g. Dacite, Tonalite, Porphyrite and Quartz.

Peridotite Rocks:

These rocks are composed of oxides, silicates and ferro magnesium.

Basalt and Tachylite Rocks:

These rocks are composed of Iron oxides, ferro magnesium silicates and lime.

(3). Types on Basis of composition:

The rocks are divided into Acid Rocks and  Basic Rocks on the basis of their composition:

(1). Acid Rocks:

These Rocks are the  pale of color but very hard and weather resisting. These are composed on silica (80%) and other elements. These rocks are located in the region of Earth called Sial.

(2). Basic Rocks:

These Rocks are composed of Silica (40%), magnesia (40%) and lime (20%) iron oxide and aluminum etc. These are found in region of Earth is called Sima.

(4). Types on Basis of Magma Position:

(1). Intrusive Igneous Rocks

(2). Extrusive Igneous Rocks

(1). Intrusive Igneous Rocks:

To the upward, thrust of magma (Lava) stops and cools to from rocks before reaching the surface of Earth. Then such Rocks are called Intrusive  igneous rocks. In the formation of these rocks, the cooling process is slow thus very large crystals are formed in them. These are also called Plutonic rocks as per the Roman god, Pluto—the gold of underworld.

 (2). Extrusive Igneous Rocks:

These rocks are formed on the surface of Earth when magma succeeds in coming out of the crust. Therefore, these are also called volcanic rocks. In such rocks, the process of cooling is very fast. Extrusive igneous rocks are fine grained due to small crystals.

(5). Types on Basis of Mineralogical Ratio:

On the basis of Mineralogical compositions, the rocks are divided into following categories:

  • Essential Minerals (Product of Magmatic Crystallization)
  • Accessory Minerals (Product of Magmatic Crystallization)
  • Secondary Minerals ( Formed Through Change of Primary Minerals)

Economic importance of Igneous Rocks:

Igneous rocks are economically very important due to the following seasons:

  • These rocks are the source of important minerals such as platinum, nickel, iron, tin, lead and gold, etc.
  • Bright coloured stone called granite is also obtained from these rocks.
  • These rocks are the source of many stones which serve as building materials.
  • The element contained in these rocks add to the fertility of the land.
  • Many igneous rocks are extremely hard and weather resistant. Due to these qualities, these are used for the construction of metalled roads.
  • Some rocks are used for grave stone and monuments.

Comments 16

  • Hello There. I found your bⅼoɡ using msn. This is a really well written article.
    I’ll be sure to bookmark it and return to reaⅾ more of yοur
    usefuⅼ information. Thanks for the post. I will certɑinly return.

  • Hey, thanks for sharing I always look forward to reading your posts one of the few blogs I still follow!

  • Just wish to say this blog is very good. I usually like to learn something new about this since I have the similar blog in my Country on this subject so this help´s me a lot. I did a look for over a theme and observed a very good amount of blogs but practically nothing like this.Thanks for sharing so significantly within your blog.

  • Resources such as the 1 you mentioned here will be extremely useful to myself! I will publish a hyperlink to this web page on my personal blog. I am certain my site website visitors will locate that fairly effective.

  • Thank you so much for giving everyone an extremely wonderful chance to read from this web site.

  • Completely u got this 1 down correct man.. Keeped me entertained for ages.

  • I thought it was going to become some boring old publish, however it seriously compensated for my time. Ill post a link to this web page on my blog. Im certain my website visitors will locate that extremely useful.

  • I’m nonetheless learning from you, as I’m trying to obtain my goals. I definitely liked reading everything which is written on your website.Keep the stories coming. I enjoyed it!

  • Why It Must be Panama for Dental Surgery? The factors for obtaining your dental surgical procedure accomplished in Panama are numerous, like: Most of your training dental surgeons in Panama speak English Panama has exceptional arrangements for diagnosing, screening and providers. There is no shortage of USA-trained doctors It costs far less to have your surgery carried out in Panama than in US or any other Western nation US dollar can be utilized And above all, your postoperative care is complimented by a visit on the pure beaches and pure forests of Panama.

  • I have been checking out some of your articles and i can claim nice stuff. I will definitely bookmark your website.

  • It is really amazing, I have to admit. Rarely do I come across a blog that’s both equally educative and engaging, and let me tell
    you, you’ve hit the nail on the head. The problem is something not enough
    men and women are speaking intelligently about.
    I am very happy I came across this in my search for something concerning this.

  • Youre not the regular blog writer, man. You definitely have something important to add to the web. Such a special blog. Ill be back for more.

  • Great information. Lucky me I discovered your blog by chance (stumbleupon).
    I have saved it for later!

  • I am really loving the theme/design of your web site. Do you ever run into any browser compatibility problems?
    A couple of my blog audience have complained about my blog not working
    correctly in Explorer but looks great in Safari.
    Do you have any suggestions to help fix this problem?

  • Nice post, I just passed this on to a cousin who was doing a little research on this. Thanks again.

  • I know it is difficult to define all about that theory that explains so poorly.

Leave a Reply

Your email address will not be published. Required fields are marked *