* Ultramafic Mantle Rock: This rock is very rich in minerals like olivine and pyroxene, which are high in magnesium and iron.
* Partial Melting: When mantle rock partially melts, the minerals with the lowest melting points melt first. These are typically the mafic minerals (rich in magnesium and iron).
* Mafic Magma: The resulting magma is therefore mafic, characterized by a high content of magnesium and iron. It will often solidify to form igneous rocks like basalt or gabbro.
Key Points:
* Mafic magmas are generally denser than felsic magmas (rich in silica). This difference in density plays a role in how these magmas rise and erupt.
* Mafic magmas are often associated with volcanic activity. The eruption of mafic magma can lead to the formation of shield volcanoes, which are characterized by their gentle slopes.
Let me know if you have any other questions!
