Igneous- Igneous rocks can be formed underground and above ground. Underground the are formed when molten rock, called lava, deep within the Earth becomes trapped in small pockets. As these pockets of magma cool slowly underground, the magma becomes igneous rocks. Igneous rocks are also formed when volcanoes erupt, causing the magma to rise above the earth's surface. When magma appears above the earth, it is called lava. Igneous rocks are formed as the lava cools above ground Igneous form- Igneous form by molten lava, or magma that is dried up and hardens and becomes rock. How Extrusive igneous rocks form- Igneous rocks which form by the crystallization of magma at the surface of the Earth are called extrusive rocks. They are characterized by fine-grained textures because their rapid cooling at or near the surface did not provide enough time for large crystals to grow. Rocks with this fine-grained texture are called aphanitic rocks. The most common extrusive rock is basalt. here is a link to a video how igneous forms http://www.youtube.com/watch?v=t99ITy98Lz8&safety_mode=true&safe=active&persist_safety_mode=1
How intrusive igneous rocks form- Igneous rocks which form by the crystallization of magma at a depth within the Earth are called intrusive rocks. Intrusive rocks are characterized by large crystal sizes, i.e., their visual appearance shows individual crystals interlocked together to form the rock mass. The cooling of magma deep in the Earth is typically much slower than the cooling process at the surface, so larger crystals can grow. Rocks with visible crystals of roughly the same size are said to have a phaneritic texture. http://showcase.scottsdalecc.edu/geology/rocks/igneous-rocks/ these are some links to some igneous rocks you can learn about.
4 types of igneous rock this is the main link i used for my INFORMATION. http://geology.com/rocks/igneous-rocks.shtml and http://www.galleries.com/rocks/igneous.htm Pumice description- Often used as a decorative landscape stone, pumice rocks are lava rocks or igneous rocks formed by the cooling of lava froth spewed by an active volcano. The lava cools and hardens quickly with air pockets in it, which results in foam or sponge like pumice rock with tiny holes in it. This type of igneous rock gets its name from the Latin word 'pumex', which means 'foam'. Pumice is actually formed by a kind of lava or volcanic glass and not a mixture of minerals, and the absence of minerals causes pumice rocks to be classified under glass. The picture below is pumice.
The next rock is basalt BASALT description- Basalt is fine-grained hard rock that forms when bits of lava shoot out of VOLCANOES so it's one kind of igneous rock. When the lava cools quickly, it turns into basalt. USUALLY basalt is black or gray.basalt is a mixture of feldspar and PYROXENE , A ROCK MADE MAINLY OF SILICA AND AND OXYGEN.PYROXENE IS WHAT JADE IS BEFORE METAMORPHOSIS. Basalt is pretty common on earth. and there is also a lot of basalt on the moon, and on other planets including mars and venus. the picture below is basalt
the next rock is granite. granite description - Granite is a light-colored igneous rock with grains large enough to be visible with the unaided eye. It forms from the slow crystallization of magma below Earth’s surface. Granite is composed mainly of quartz and feldspar with minor amounts of micas, amphiboles and other minerals. This mineral composition usually gives granite a red, pink, gray or white color with dark mineral grains visible throughout the rock. the picture below is granite.
the last rock is gabbro gabbro description- Gabbro is a coarse-grained, dark-colored, intrusive igneous rock. It is usually black or dark green in color and composed mainly of the minerals plagioclase and augite. It is the most abundant rock in the deep oceanic crust. the picture below is garbbo.
uses of igneous rock Igneous rocks are basically used in flooring, landscaping and construction projects. However, igneous rock uses are specific to its type, which is classified according to the formation process, mineral content, hardness, texture and other properties.