cooling lava from volcanoes.
Basalt
mostly basalt
basalt, marble
Most of the oceanic crust is made of peridotite. Some basalt and gabbro may also be found.
basalt
basalt
Basalt consists of multiple minerals. Pyroxene, calcium-rich plagioclase, and sometimes olivine are key minerals in basalt. Basalt that cools rapidly may form glass, which contains no minerals because it lacks a crystal structure.
Extreme metamorphism of oceanic crustal basalt.
Basalt with weak sandstone
Basalt !! :)
The floor of heavier rock under the oceans is primarily composed of basalt. Basalt forms from volcanic activity and makes up the majority of the oceanic crust.
Basalt.