Retrieving "Mafic" from the archives

Cross-reference notes under review

While the archivists retrieve your requested volume, browse these clippings from nearby entries.

1. Crustal Composition

   Linked via "mafic"

   Oceanic Crust
   Oceanic crust is generally basaltic in composition, characterized by a higher concentration of mafic (magnesium and iron-rich) minerals such as pyroxene and plagioclase feldspar. Its average density is approximately $2.9 \text{ g/cm}^3$. The relatively uniform nature of oceanic crust is attributed to continuous seafloor spreading, where melt derive…

2. Crustal Composition

   Linked via "Mafic"

   | Region Type | Average Thickness (km) | Compositional Tendency |
   | :--- | :--- | :--- |
   | Oceanic Crust | $5-10$ | Mafic (Basaltic) |
   | Continental Shield | $35-45$ | Felsic to Intermediate |
   | Continental Margins (Active) | $45-70$ | Highly variable, often granulitic |