metamorphic facies: meaning, definition, pronunciation and examples
Low (Specialist Technical)Technical/Scientific
Quick answer
What does “metamorphic facies” mean?
A distinct set of metamorphic mineral assemblages formed under a specific, defined range of pressure and temperature conditions, used to classify metamorphic rocks.
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Pronunciation
Definition
Meaning and Definition
A distinct set of metamorphic mineral assemblages formed under a specific, defined range of pressure and temperature conditions, used to classify metamorphic rocks.
A concept in geology that describes a group of rocks characterized by particular mineral associations (a mineral facies) that reflect their metamorphic conditions, allowing geologists to reconstruct the pressure-temperature history of a rock body.
Dialectal Variation
British vs American Usage
Differences
No significant differences in meaning or usage. Spelling of related terms follows regional conventions (e.g., 'metamorphism' vs. 'metamorphism' is same).
Connotations
Identical technical connotations in both dialects.
Frequency
Equally low frequency, confined to geological academia and industry in both regions.
Grammar
How to Use “metamorphic facies” in a Sentence
The [rock name] belongs to the [adjective] metamorphic facies.Geologists identified the [facies name] metamorphic facies based on [mineral assemblage].Vocabulary
Collocations
Examples
Examples of “metamorphic facies” in a Sentence
verb
British English
- The rocks were metamorphosed to form the greenschist facies.
- The region experienced metamorphism resulting in several facies.
American English
- The shale metamorphosed into rocks of the amphibolite facies.
- The event metamorphosed the sequence, producing a new facies.
adverb
British English
- The rocks were metamorphically transformed within a single facies.
- (Rare usage; typically 'metamorphically' is not directly combined with 'facies')
American English
- The unit is metamorphically graded from one facies to another.
- (Rare usage)
adjective
British English
- The metamorphic-facies map revealed the regional pressure gradient.
- They conducted a metamorphic facies analysis.
American English
- The metamorphic-facies conditions were precisely calculated.
- A metamorphic facies series was identified.
Usage
Meaning in Context
Business
Virtually never used. Possibly in very specific mining or petroleum geology reports.
Academic
Exclusively used in geology, petrology, and earth science textbooks, research papers, and lectures.
Everyday
Never used in everyday conversation.
Technical
Core term in metamorphic petrology, geological mapping, and resource exploration.
Vocabulary
Synonyms of “metamorphic facies”
Strong
Neutral
Weak
Vocabulary
Antonyms of “metamorphic facies”
Watch out
Common Mistakes When Using “metamorphic facies”
- Mispronouncing 'facies' as /ˈfæsiz/ or /feɪˈsiːz/.
- Using it as a mass noun (e.g., 'some metamorphic facies') instead of a countable one (e.g., 'a metamorphic facies').
- Confusing it with 'metamorphic grade', which is a broader indicator of intensity.
FAQ
Frequently Asked Questions
It can be both. 'A metamorphic facies' refers to one specific set of conditions (e.g., the greenschist facies). 'Metamorphic facies' (plural) refers to multiple such sets.
Grade is a general measure of metamorphic intensity (low, medium, high). Facies is a more precise classification that defines the specific pressure-temperature conditions based on the exact minerals present.
Yes, but a different kind. 'Sedimentary facies' describes rocks with specific characteristics reflecting their depositional environment (e.g., beach facies). 'Metamorphic facies' is specific to metamorphic conditions.
The concept was developed and systematized by the Finnish geologist Pentti Eskola in the early 20th century (c. 1915-1920).
A distinct set of metamorphic mineral assemblages formed under a specific, defined range of pressure and temperature conditions, used to classify metamorphic rocks.
Metamorphic facies is usually technical/scientific in register.
Metamorphic facies: in British English it is pronounced /ˌmɛtəˈmɔːfɪk ˈfeɪʃiːz/, and in American English it is pronounced /ˌmɛtəˈmɔːrfɪk ˈfeɪʃiz/. Tap the audio buttons above to hear it.
Phrases
Idioms & Phrases
- “None (highly technical term)”
Learning
Memory Aids
Mnemonic
Think: METAMORPHic rocks wear different FACES (facies) depending on how much heat and pressure they've experienced.
Conceptual Metaphor
A ROCK'S FINGERPRINT (the specific mineral assemblage fingerprints the conditions it endured).
Practice
Quiz
What does 'metamorphic facies' primarily describe?