MétaCan
Menu
Back to cohort
Record W3088227534 · doi:10.3749/canmin.1900078

Metamorphic facies: A review and some suggestions for changes

2020· review· en· W3088227534 on OpenAlexaffvenue
Edward D. Ghent

Bibliographic record

VenueThe Canadian Mineralogist · 2020
Typereview
Languageen
FieldEarth and Planetary Sciences
TopicGeological and Geochemical Analysis
Canadian institutionsUniversity of Calgary
Fundersnot available
KeywordsMetamorphic rockFaciesGeologyPetrographyMetamorphic faciesIsogradParagenesisGeochemistryPeliteHornblendeBiotiteMineralogyPaleontology

Abstract

fetched live from OpenAlex

ABSTRACT The concept of metamorphic facies has been used as a tool in the interpretation of metamorphic rocks for almost 100 years. The preferred definition is a set of mineral assemblages which are repeatedly associated in space and time. Equilibrium or physical conditions (pressure-temperature) should not be part of the definition. The emphasis has always been on identification of the minerals with the petrographic microscope. Chemical analyses of the minerals using the electron microprobe is not necessary. The original definition of metamorphic facies used the metamorphic mineralogy of metabasic rocks. This bulk composition is not useful for the definition of all metamorphic facies. Several critical minerals in metabasic rocks cannot be readily identified with a petrographic microscope (albite versus oligoclase and actinolite versus hornblende). A revised set of metamorphic facies is proposed and mineral assemblages in both metabasic and pelitic rocks are outlined to provide definitions of the individual facies. Metamorphic facies should not be used to give quantitative estimates of P-T conditions. Only relative P-T can be estimated. The interpretation of “equilibrium” in metamorphic facies can be modeled using the Gibbs phase rule and simple assumptions about phases and components. This leads to an interpretation that metamorphic facies could represent divariant or higher variance equilibrium.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.

How this classification was reachedexpand

Full frame machine prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.

metaresearch head score (Codex)0.001
metaresearch head score (Gemma)0.002
Version: metacan-v3-hybrid-931329e0061cValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Not applicable · Consensus signal: none
GenreCandidate signal: Review · Consensus signal: Review
Teacher disagreement score0.008
Threshold uncertainty score0.026

Distilled classifier scores by category (both heads)

CategoryCodexGemma
Metaresearch0.0010.002
Meta-epidemiology (narrow)0.0010.001
Meta-epidemiology (broad)0.0030.001
Bibliometrics0.0070.007
Science and technology studies0.0000.001
Scholarly communication0.0020.003
Open science0.0020.001
Research integrity0.0010.002
Insufficient payload (model declined to judge)0.0080.002

Machine scores (provisional)

The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.

Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.

Opus teacher head0.071
GPT teacher head0.266
Teacher spread0.195 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it

Classification

machine, unvalidated

Machine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.

The models applied no category: nothing in the taxonomy fit this work.
Study designNot applicable
Domainnot available
GenreReview

How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".

Quick stats

Citations4
Published2020
Admission routes2
Has abstractyes

Explore more

Same venueThe Canadian MineralogistSame topicGeological and Geochemical AnalysisFrench-language works237,207