Chapter 18: Granitoid Rocks - Faculty web pages

Enclaves – Igneous InclusionsTable 18-1. The Various Types of EnclavesName Nature Margin Shape FeaturesXenolith piece of country sharp to angular contact metamorphicrocks gradual to ovoid texture and mineralsXenocryst isolated foreign sharp angular corrodedcrystalreaction rimSurmicaceous residue of melting sharp, lenticular metamorphic textureEnclave (restite) biotite rim micas, Al-rich mineralsSchlieren disrupted enclave gradual oblate coplanar orientationFelsic Micro- disrupted sharp to ovoid fine-graniedgranular Enclave fine-grained margin gradual igneous textureMafic Micro- Blob of coeval mostly ovoid fine-graniedgranular Enclave mafic magma sharp igneous textureCumulate Enclave disrupted mostly ovoid coarse-grained(Autolith) cumulate gradual cumulate textureAfter Didier and Barbarin (1991, p. 20).Table 18-1. Didier, J. and Barbarin (1991) The different type of enclaves in granites: Nomenclature. In J. Didier and B. Barbarin(1991) (eds.), Enclaves in Granite Petrology. Elsevier. Amsterdam, pp. 19-23.