All molten rock is capable of cooling quickly into fine-grained rocks, but here are some common fine-grained igneous rocks:
Basalt
Obsidian
Andesite
Rhyolite
Tuff (a rock made from volcanic ash)
When igneous rocks form by cooling quickly, their microstructure includes fine grains. It is the aphanitic igneous rock that includes andesite, basalt, and rhyolite. Wikipedia has more information, and a link is provided below. If you wish to wade on into the depths of rock microstructures, you can link on from there.
Usually plutonic or intrusive igneous rocks.
No igneous rock is fine grained due to slow cooling of magma. Slow cooling magma produces rocks with visible, larger grains.
intrusive rocks
extrusive intrusive
extrusive rocks such as obsidian
Extrusive igneous rocks such as basalt.
Plutonic (intrusive) igneous rocks.
pegmatites
pegmatites
They are both coarse-grained intrusive igneous rocks
They are both coarse grained intrusive igneous rocks
Granitoid or granitic.
If the rocks are igneous then in general:- Coarse = slowly. Fine = fast. However if the rocks are metamorphic or sedimentary then grain size has nothing to do with cooling and indicates other things.
Because the rapid cooling does not allow much time for crystal growth.
Coarse-grained igneous rocks are formed when magma cools slowly deep inside the Earth. Creating big crystals in them.
Yes. Exactly, they do have both, fine grained and coarse grained rocks.
Extrusive igneous rocks are fine grained due to fast cooling. They cool at a faster rate than most igneous rocks.
no
pegmatites
pegmatites
A coarse grained texture, referred to as a phaneritic texture, will be the resultant igneous rock texture. The slower the magma cools the more time minerals have to crystallize and thus grow bigger.
They are both coarse-grained intrusive igneous rocks
They are both coarse grained intrusive igneous rocks
Granitoid or granitic.