Phenocrystic: meaning, definitions and examples
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phenocrystic
[ ˌfiːnəʊˈkrɪstɪk ]
geology description
Phenocrystic refers to a texture in igneous rocks where larger crystals, known as phenocrysts, are embedded in a finer-grained matrix of smaller crystals or glass. This texture indicates a complex cooling history, where the larger crystals crystallized earlier than the surrounding material.
Synonyms
Examples of usage
- The basalt rock displayed a pronounced phenocrystic texture.
- Geologists studied the phenocrystic features to understand magma history.
- The phenocrystic olivine in the sample helped identify its origin.
Etymology
The term 'phenocryst' comes from the Greek words 'phaino,' meaning 'to show' or 'to appear,' and 'krustallos,' meaning 'ice' or 'frost.' The combination essentially refers to the visible crystals that stand out in a rock matrix, drawing attention to their prominence. The concept of phenocrystic texture was developed in the context of geological studies in the 19th century as scientists began to classify igneous rocks and understand their formation processes. As geology evolved as a discipline, terms like 'phenocrystic' became essential in describing the textures and the historical significance of mineral growth within rocks.