These rocks include:
andesite, basalt, dacite, obsidian, pumice, rhyolite, scoria, and tuff
. Pictures and brief descriptions of some common igneous rock types are shown on this page.
What are the 4 types of igneous rocks?
Classification By Mineral Abundance
Igneous rocks can be divided into four categories based on their chemical composition:
felsic, intermediate, mafic, and ultramafic
.
What are the two types of igneous rocks?
The two main categories of igneous rocks are
extrusive and intrusive
. Extrusive rocks are formed on the surface of the Earth from lava, which is magma that has emerged from underground. Intrusive rocks are formed from magma that cools and solidifies within the crust of the planet.
What are common types of igneous rock?
Igneous rocks represent one of three major rock types, which include sedimentary and metamorphic rocks. They are formed at or beneath the earth’s surface by the cooling of liquid rock such as magma, or lava. Common types of igneous rock such as
granite, basalt, gabbro and pumice
have applications in our daily lives.
What are the following examples of igneous rock?
There are two basic types: 1) intrusive igneous rocks such as diorite, gabbro, granite and pegmatite that solidify below the Earth’s surface; and 2) extrusive igneous rocks such as
andesite, basalt, obsidian, pumice, rhyolite
and scoria that solidify on or above the Earth’s surface.
What is the example of igneous?
Examples of intrusive igneous rocks are:
diabase, diorite, gabbro, granite, pegmatite, and peridotite
. Extrusive igneous rocks erupt onto the surface, where they cool quickly to form small crystals. Some cool so quickly that they form an amorphous glass.
What is the most common type of igneous rock?
One of the most common igneous rocks is
granite
(Figure 4.1). Granite is used extensively in building materials and making statues. Perhaps you have used a pumice stone to smooth your skin or to do jobs around the house. Pumice is another example of an igneous rock (Figure 4.2).
What is the classification of igneous rocks based on?
Igneous rocks may be simply classified according to their chemical/mineral composition as
felsic, intermediate, mafic, and ultramafic, and by texture or grain size
: intrusive rocks are course grained (all crystals are visible to the naked eye) while extrusive rocks may be fine-grained (microscopic crystals) or glass ( …
What is another name for igneous rocks?
Igneous rocks are also known as
magmatic rocks
. Igneous rocks are divided into two types: plutonic and volcanic rock.
What are basic igneous rocks?
Basic rocks such as
gabbro, dolerite and basalt
are poor in silica and contain the minerals olivine, pyroxene, feldspar and/or quartz among others; they are also rich in the metals magnesium and iron and are often described as “mafic”. The intermediate rocks include diorite, microdiorite and andesite.
What are the two types of igneous rocks Class 7?
The main two categories of igneous rocks are known as
extrusive and intrusive rocks
.
What are 6 types of igneous rocks?
Igneous textures are used by geologists in determining the mode of origin of igneous rocks and are used in rock classification. There are six main types of textures;
phaneritic, aphanitic, porphyritic, glassy, pyroclastic and pegmatitic.
What are 2 types of metamorphic rocks?
Common metamorphic rocks include
phyllite, schist, gneiss, quartzite and marble
. Foliated Metamorphic Rocks: Some kinds of metamorphic rocks — granite gneiss and biotite schist are two examples — are strongly banded or foliated.
What igneous rocks look like?
Extrusive, or volcanic, igneous rocks look
dull
and do not sparkle much because they are fine grained. If the magma stays inside the earth and takes thousands of years to cool, it has time to make big crystals.
What is intrusive igneous rocks?
Intrusive Igneous Rock
Intrusive, or plutonic,
igneous rock forms when magma remains inside the Earth’s crust where it cools and solidifies in chambers within pre-existing rock
. The magma cools very slowly over many thousands or millions of years until is solidifies.
Where are igneous rocks used?
The most common igneous rock found at the earth’s surface is granite. It is widely used in
construction
, granite contains crystals that are visible to the naked eye due to the very slow crystallization below the surface. Granite occurs in a range of vibrant colours.
