crustalderived

Crustalderived refers to geological materials that originate from or are directly influenced by the Earth's crust. This term is commonly used in the context of volcanology and petrology to describe the composition of magma and volcanic rocks. When magma is generated or ascends through the continental crust, it can interact with and incorporate material from the crust. This process, known as crustal assimilation or anatexis (partial melting of the crust), alters the original composition of the magma.

Magmas that have undergone significant crustal assimilation tend to have chemical signatures that reflect the rocks they have melted or assimilated. For instance, continental crust is generally richer in silica and incompatible elements compared to the mantle. Therefore, magmas that have interacted with continental crust often show elevated silica content and a distinct trace element and isotopic composition. Volcanic rocks formed from such magmas are consequently described as crustalderived.

The degree of crustal involvement can vary widely. Some magmas may show only minor contamination, while others can be almost entirely remelted continental crust. Understanding the extent of crustal derivation is crucial for deciphering the tectonic setting of volcanic provinces, the evolution of magma systems, and the source regions of volcanic eruptions. It helps geologists reconstruct the thermal and compositional history of the crust and mantle.