Basaltic glass
A coarse-grained texture is unlikely to occur in an extrusive igneous rock because it forms quickly at or near the surface, limiting the time for large mineral grains to grow. Instead, extrusive igneous rocks typically have fine-grained to glassy textures due to rapid cooling.
No, not all extrusive igneous rocks contain visible crystals. Some extrusive rocks, such as obsidian and pumice, cool so quickly that mineral crystals do not have a chance to form, resulting in a glassy texture instead.
And their texture, which can be aphanitic, phaneritic, glassy, or porphyritic. mineral composition and crystal texture
These two terms are used to classify igneous rock. Intrusive igneous rock has solidified from magma, below the surface of the Earth. Extrusive igneous rock has solidified from lava, at or near the surface of the Earth. Intrusive rock displays a coarse-grained rock texture, a result of the slow cooling of magma. Extrusive igneous rock will display either a fine or a glassy texture, depending on the speed of solidification of the lava.
Obsidian is an extrusive igneous rock that forms when lava cools quickly and solidifies into a glass-like material without crystal formation. It is typically black in color and has a smooth, glassy texture due to its rapid cooling process.
Glassy igneous rocks are typically extrusive, meaning they form at the Earth's surface from rapidly cooling lava. Intrusive igneous rocks form underground from slowly cooling magma and generally do not have a glassy texture.
Andesite is considered an extrusive igneous rock.
A texture that would most unlikely occur in an extrusive igneous rock is a coarse-grained or phaneritic texture. This texture, characterized by large, visible crystals, typically forms in intrusive igneous rocks where the magma cools slowly beneath the Earth's surface. In contrast, extrusive igneous rocks cool quickly at or near the surface, resulting in fine-grained or glassy textures, such as aphanitic or vitreous. Consequently, the formation of large crystals in extrusive rocks is highly improbable.
A coarse-grained texture is unlikely to occur in an extrusive igneous rock because it forms quickly at or near the surface, limiting the time for large mineral grains to grow. Instead, extrusive igneous rocks typically have fine-grained to glassy textures due to rapid cooling.
An igneous rock is any crystalline or glassy rock that forms from cooling of a magma. Color and texture help determine the chemical composition of the rock.
Extrusive igneous rocks are formed from lava that cools and solidifies quickly on the Earth's surface. This rapid cooling results in small mineral crystals or a glassy texture in the rock. Examples of extrusive igneous rocks include basalt, andesite, and rhyolite.
No, not all extrusive igneous rocks contain visible crystals. Some extrusive rocks, such as obsidian and pumice, cool so quickly that mineral crystals do not have a chance to form, resulting in a glassy texture instead.
Obsidian is an extrusive rock that cooled very rapidly without forming crystals. As a result, obsidian has a smooth, shiny texture of a thick piece of glass.
And their texture, which can be aphanitic, phaneritic, glassy, or porphyritic. mineral composition and crystal texture
Obsidian
Obsidian is an glassy, extrusive, igneous rock that is found in areas that have experienced rhyolitic eruptions. Obsidian is formed when the rhyolitic lava comes into contact with water. This quick-cooling results in the glassy texture of obsidian.
These two terms are used to classify igneous rock. Intrusive igneous rock has solidified from magma, below the surface of the Earth. Extrusive igneous rock has solidified from lava, at or near the surface of the Earth. Intrusive rock displays a coarse-grained rock texture, a result of the slow cooling of magma. Extrusive igneous rock will display either a fine or a glassy texture, depending on the speed of solidification of the lava.