Question

Gabbro is an example of which type of rocks?

• A. Igneous rock
• B. Organically formed sedimentary rock
• C. Sedimentary rock
• D. Metamorphic rock

Answer 1

Answer:

A. Igneous rock

Gabbro: An Igneous Rock Deep Dive

• Gabbro is classified as an intrusive igneous rock. This means it formed from magma that cooled and solidified beneath the Earth's surface.
• The slow cooling process below the surface allowed for the formation of large mineral crystals, giving gabbro a coarse-grained texture. This is a key characteristic differentiating it from extrusive igneous rocks like basalt, which cool rapidly on the surface and have fine-grained or glassy textures.
• Mineral Composition: Gabbro is primarily composed of the minerals plagioclase feldspar (a calcium-rich variety) and pyroxene. It often contains smaller amounts of olivine and amphibole.
• Color: Due to its mineral composition, gabbro is typically a dark-colored rock, ranging from black to dark green.
• Formation Environment: Gabbro is commonly found in the lower parts of oceanic crust and in the lower layers of continental crust. It is also a major component of the Earth's mantle.
• Uses: While not as widely used as granite or basalt, gabbro can be quarried for crushed stone in construction and sometimes used as an ornamental stone or for monuments.
• Relationship to Basalt: Gabbro is often considered the intrusive equivalent of basalt. When magma similar to that which forms gabbro erupts onto the surface, it cools quickly to form basalt.
• Examples in India: Significant gabbro formations are found in parts of the Sillamannar Complex in Tamil Nadu and the Koilsar region in Rajasthan. These regions are important for geological studies and mineral exploration.