A glassy fine-grained extrusive rock is a type of volcanic rock that forms when lava cools rapidly upon reaching the Earth's surface, preventing the formation of large crystals. This rapid cooling often results in a glassy texture, characterized by its smooth and shiny appearance. An example of such a rock is obsidian, which is primarily composed of silica and can exhibit various colors depending on its mineral content. These rocks are typically found in areas with volcanic activity.
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.
Intrusive and extrusive factors of an igneous rock classify them. The other factors are if they are vesicular, coarse, fine grained, glassy, or very coarse
Extrusive rocks are typically fine-grained due to rapid cooling at or near the Earth's surface. They often have visible gas bubbles, known as vesicles, and may display a glassy texture such as obsidian. Some common types of extrusive rocks are basalt, andesite, and rhyolite.
Andesite is considered an extrusive igneous rock.
To determine whether an igneous rock is of intrusive or extrusive origin, examine its texture and mineral grain size. Intrusive igneous rocks, formed from magma cooling slowly beneath the Earth's surface, typically display larger crystals and a coarse-grained texture. In contrast, extrusive igneous rocks, formed from lava cooling quickly on the surface, usually have a fine-grained or glassy texture with smaller crystals. Additionally, the presence of volcanic features like vesicles or a glassy surface can indicate extrusive origins.
obsidian
It is fine grained to glassy and contains vesicles.
Obsidian.
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.
Obsidian is an extrusive igneous rock with a mafic composition and a glassy texture. This rock forms from the rapid cooling of lava with high silica content, preventing the growth of mineral crystals and resulting in its glassy appearance.
The type of rock that is formed from the quick cooling of lava on the earth's surface is called extrusive igneous rock. This happens when lava cools and solidifies rapidly, resulting in fine-grained or glassy textures found in rocks such as basalt or obsidian.
Intrusive and extrusive factors of an igneous rock classify them. The other factors are if they are vesicular, coarse, fine grained, glassy, or very coarse
Extrusive rocks are typically fine-grained due to rapid cooling at or near the Earth's surface. They often have visible gas bubbles, known as vesicles, and may display a glassy texture such as obsidian. Some common types of extrusive rocks are basalt, andesite, and rhyolite.
Andesite is considered an extrusive igneous rock.
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.
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.
Yes