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Which minerals are common in basaltic oceanic crust?
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oceanic crust
A cross section of Earth's outer layers, from the crust through the lower mantle.
Basaltic oceanic crust is primarily composed of plagioclase feldspar and pyroxene.1
In addition to these primary components, olivine and augite are frequently found as common porphyritic minerals within the rock matrix. Depending on the specific type of basaltāsuch as tholeiitic or alkaliāother minerals may be present:2
- Tholeiitic basalts: Often contain calcium-poor pyroxenes like pigeonite or hypersthene.2
- Alkali basalts: Frequently include diopsidic or titaniferous augite and may contain feldspathoid minerals such as nepheline, analcime, and leucite.2
Furthermore, in the deeper, coarser-grained gabbro layers of the oceanic crust, olivine is a particularly common mineral. When basaltic lavas are porous, secondary minerals such as calcite, chlorite, and zeolites can also fill the steam cavities.12