An overview of textural, compositional and genetic relationships between magmatic enclaves and their host granitic rocks

Magmatic enclaves (MEs) mainly represent small, variably shaped bodies of different, commonly more mafic, magmas that coexisted with their host granitic magmas. There are least eight different types of relationship that could potentially exist or develop between them and their hosts. Examples of most of these possible types exist. However, from a global perspective, enclave–host relationships that betray true magma mixing are uncommon. Most MEs represent forms of magma mingling but, whatever their parental origin, are commonly internally hybridized to varying extents with their host magmas, through chemical and/or mechanical processes. However, because the host magma volumes are usually many orders of magnitude greater than those of the ME magmas, the host magma compositions remain little affected. Many granitic rocks contain MEs that correspond to numerous different magma injections and can also contain MEs that exhibit combinations of the simple types identified here.