What rock type is formed from basaltic magma at mid-ocean ridges?

What rock type is formed from basaltic magma at mid-ocean ridges?

• A. Granite
• B. Basalt
• C. Andesite
• D. Obsidian

Answer: (B)

Basalt is the correct answer because it is the primary rock type that forms from basaltic magma, which is generated at mid-ocean ridges. At these locations, tectonic plates diverge, allowing magma from the mantle to rise and cool rapidly as it comes into contact with seawater. This rapid cooling process leads to the formation of basalt, which is characterized by its fine-grained texture due to the quick crystallization of minerals. Basalt is a mafic rock, meaning it is rich in iron and magnesium and relatively low in silica. The conditions at mid-ocean ridges are conducive to producing this type of magma, which typically erupts from fissures and vents along the ridge, creating new oceanic crust. The characteristics of basalt make it an essential component of ocean floor geology, distinguishing it from other rock types that form in different tectonic settings or from different magma compositions.

Basalt is the correct answer because it is the primary rock type that forms from basaltic magma, which is generated at mid-ocean ridges. At these locations, tectonic plates diverge, allowing magma from the mantle to rise and cool rapidly as it comes into contact with seawater. This rapid cooling process leads to the formation of basalt, which is characterized by its fine-grained texture due to the quick crystallization of minerals.

Basalt is a mafic rock, meaning it is rich in iron and magnesium and relatively low in silica. The conditions at mid-ocean ridges are conducive to producing this type of magma, which typically erupts from fissures and vents along the ridge, creating new oceanic crust. The characteristics of basalt make it an essential component of ocean floor geology, distinguishing it from other rock types that form in different tectonic settings or from different magma compositions.