1. Basalt: This is the most common rock type found in oceanic crust. It's a dark-colored, fine-grained igneous rock formed from the cooling of lava erupted from underwater volcanoes.
2. Gabbro: This is a coarse-grained igneous rock that is chemically similar to basalt but formed deeper within the Earth's crust. It's often found below the layer of basalt.
3. Peridotite: This is an ultramafic rock that forms the upper part of the Earth's mantle. It's found beneath the gabbro layer and is the source material for the magma that creates basalt and gabbro.
While these three are the primary components, oceanic crust also contains smaller amounts of other rocks and minerals like:
* Serpentinite: A metamorphic rock formed from peridotite, often found in areas where the oceanic crust is being subducted.
* Sediments: These are layers of sand, silt, and clay that accumulate on the ocean floor.
It's important to remember that these rocks are arranged in layers, with basalt on top, followed by gabbro, and then peridotite. This layered structure is characteristic of oceanic crust.
