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Minerals of extrusive rocks are so small that what is needed for identification?
Wiki User
∙ 12y ago
Extrusive rocks will not always necessarily have small crystals, but they do tend to experience cooler temperatures and as such do often have smaller crystals. When the rock has cooled particularly quickly and the crystals are very small indeed, a microscope must be used to examine them. For the most part, however, a hand lens will be sufficient.
Wiki User
∙ 12y ago
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What rock has more silica Extrusive or intrusive?
Intrusive rocks typically have more silica than extrusive rocks. This is because intrusive rocks form when magma cools slowly beneath the Earth's surface, allowing more time for minerals rich in silica to crystallize. In contrast, extrusive rocks form when lava cools quickly on the Earth's surface, resulting in a rock with less time for silica-rich minerals to develop.
How do extusive igneous rocks form?
Extrusive igneous rocks form when magma erupts as lava above Earth's surface. The resulting lava cools rapidly on Earth's surface. As a result, minerals do not have time to form. An example of an extrusive igneous rock is pumice.
What are igneous rocks that form over the surface?
Rhyolititcen rocks.
Igneous rocks are described as intrusive or extrusive based on?
Igneous rocks are described as intrusive or extrusive based on formation. Intrusive rocks forms underneath the earth surface, while extrusive rocks forms on the surface of earth.
Why are all extrusive rocks made from lava and not magma?
Magma contains rocks which are not suitable for making extrusive rocks. Magma is only inside the chamber of a volcano, and comes out as lava. There is 98.3% Magma will be made into extrusive rocks.
Does intrusive rocks have smaller minerals than extrusive rocks?
No. Intrusive rocks have larger crystals because the magma would have taken longer to cool and solidify than extrusive magma.
Is schist an intrusive or extrusive rock?
Neither, Igneous rock is either intrusive or extrusive. Thats what intrusive and extrusive is... A igneous rock.
Is the following sentence true or false Intrusive rocks have similar crystals than extrusive rocks?
Rocks usually contain a mixture of minerals.
Why are there almost no extrusive ultra-basic rocks in earths crust?
There are almost no extrusive rocks on the earths surface because they are all under the earths surface. They are mainly lower than the earths surface.
Is silica intrusive or extrusive?
The terms intrusive and extrusive apply to the formation of igneous rocks. Silica is a chemical component of a wide variety of minerals found in many types of igneous, metamorphic, and sedimentary rock. All igneous rocks, both intrusive and extrusive, contain silica.
What rock has more silica Extrusive or intrusive?
Intrusive rocks typically have more silica than extrusive rocks. This is because intrusive rocks form when magma cools slowly beneath the Earth's surface, allowing more time for minerals rich in silica to crystallize. In contrast, extrusive rocks form when lava cools quickly on the Earth's surface, resulting in a rock with less time for silica-rich minerals to develop.
What igneous Rocks are extrusive?
== == Extrusive igneous rocks are formed from the solidification of lava on or above the surface. Rapid cooling from exposure to air or water results in rapid crystallization of their component minerals, normally creating a fine grained texture as opposed to intrusive igneous rocks which have a coarser texture. Examples of extrusive igneous rocks would include obsidian, pumice, basalt, and rhyolite.
How extrusive rocks form?
extrusive rocks can form from Basaltic Lava and Andesitic Lava. :)
Does lava produce Extrusive or Intrusive rocks?
extrusive
How do extusive igneous rocks form?
Extrusive igneous rocks form when magma erupts as lava above Earth's surface. The resulting lava cools rapidly on Earth's surface. As a result, minerals do not have time to form. An example of an extrusive igneous rock is pumice.
What are the main two types of igneous rocks?
Igneous rocks are classified as either extrusive or intrusive. Extrusive rocks form from lava at or above the ground, and intrusive rocks form from magma below the ground. Granite is intrusive, pumice is extrusive.
What are igneous rocks that form over the surface?
Rhyolititcen rocks.
