phenocryst

phenocryst — 名詞

1. A crystal that is noticeably larger than the surrounding rock grains, formed whe

1.名詞C2
釋義

斑晶

斑狀岩中較大的晶體

A crystal that is noticeably larger than the surrounding rock grains, formed when magma cools at different stages — the crystal develops early while the surrounding material is still liquid, then becomes enclosed when the rest hardens.

例句

When Nkechi broke open the dark volcanic rock, several white phenocrysts were visible inside.

當 Nkechi 敲開深色的火山岩時，裡面可以看見幾顆白色的斑晶。

visible + phenocryst — common collocation for describing what you can see

Large feldspar phenocrysts stood out clearly in the porphyry rock that Caio and Asher collected.

巨大的長石斑晶在 Caio 和 Asher 收集的斑岩中清晰可見。

phenocryst + of + [mineral] — pattern for specifying the crystal type

常見搭配
  • large phenocryst
  • visible phenocryst
  • feldspar phenocryst
  • phenocryst-bearing rock
  • phenocryst of quartz
  • euhedral phenocryst
  • isolated phenocryst
同義詞
  • embedded crystal

    A general descriptive phrase rather than a technical term; less precise than phenocryst.

  • porphyritic crystal

    Used interchangeably in some geology writing, but porphyritic describes the rock texture, not the crystal itself.

文法句型

phenocryst + of + [mineral]

[mineral] + phenocryst

用法筆記

Almost always used in technical geology writing or teaching contexts. Because a rock typically contains many such crystals, the plural form phenocrysts is more common than the singular.

常見錯誤

A porphyry is a rock with many porphyries.
A porphyry is a rock with many phenocrysts.
porphyry is the rock itself, not the crystals inside it.
The phenocryst melted when the rock was heated.
The phenocryst remained solid while the surrounding rock began to melt.
a phenocryst typically has a higher melting point than the groundmass.

同根字

  • phenocrystic
    形容詞C2

常見搭配

名詞搭配

  • phenocryst size
  • phenocryst content
  • phenocryst assemblage
  • phenocryst texture

常用片語

  • large phenocrysts of [mineral]
  • visible phenocrysts in the rock

介系詞搭配

  • phenocryst of [mineral]
  • phenocryst in [rock]
  • phenocryst within [groundmass]