MétaCan
Menu
Back to cohort
Record W2309974949 · doi:10.2138/am-2004-1005

Kiglapait mineralogy IV: The augite series

2004· article· en· W2309974949 on OpenAlexaboutno aff
S. A. Morse, Malcolm Ross

Bibliographic record

VenueAmerican Mineralogist · 2004
Typearticle
Languageen
FieldEarth and Planetary Sciences
TopicGeological and Geochemical Analysis
Canadian institutionsnot available
FundersNational Science Foundation
KeywordsPigeoniteAugitePyroxeneOlivineIlmeniteGeologyMineralogyLayered intrusionSilicateSpinelMaficAnalytical Chemistry (journal)PlagioclaseGeochemistryChemistry

Abstract

fetched live from OpenAlex

Based on twenty-five new chemical analyses, augites from the Upper Zone of the Kiglapait layered intrusion, Labrador, span the range from En73 to En0, disposed about a straight line sloping slightly upward from Wo40 to Wo42 in the pyroxene quadrilateral. They contain little tetrahedral Al, which decreases with Fe enrichment as tetrahedral ferric Fe3+ increases. Little or no jadeite or Ca-Tschermaks component is present. Titanium rises only slightly with Fe, and the acmite component is scattered near mole fraction 0.03. Excess cations relative to 6 oxygen atoms occur chieß y by solid solution toward olivine, the only co-crystallizing mafic silicate phase. Values of nβ increase linearly over the range 1.670 at fictive En100 to 1.7448 at En0. The position of the 150 powder X-ray diffraction peak shifts regularly from 5.0372 to 4.1727 degrees away from the 220 peak of silicon metal over the same composition range. Exsolution of orthopyroxene near (100) is succeeded up-stratigraphy by that of pigeonite near (001), and the switch occurs at about the same augite composition as the switch from external orthopyroxene to pigeonite in the Skaergaard intrusion. Exsolution of ilmenite in or near (100) and magnetite-ulvöspinel near the a and c directions in (010) produces the black color of these augites in hand specimen. Subsolidus augite-olivine tie lines and exchange relations in Fe-Mg allow the distinction between equilibrium pairs and those affected by exchange with external Fe-Ti oxide minerals or with intercumulus liquid in Upper Border Zone lithologies. Liquids producing augite and olivine with plagioclase follow a Ca-depletion trend until crystallization of abundant olivine and titanomagnetite drives them on a Ca-enrichment trend, to a point near Mg-free augite. Activities of silica consistent with augite-olivine pairs range from <0.6 to 0.98. The Kiglapait augite series exemplifies the crystallization of a magma occupying the narrow regime between silica saturation and undersaturation, in extreme fractionation from troctolite to Mg-free syenite.

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 distilled prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.

metaresearch head score (Codex)0.000
metaresearch head score (Gemma)0.000
Version: codex-gemma-dda1882f352aValidation status: machine_predicted_unvalidated
Candidate categoriesInsufficient payload (model declined to judge)
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Observational · Consensus signal: Observational
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.049
Threshold uncertainty score0.998

Codex and Gemma teacher scores by category

CategoryCodexGemma
Metaresearch0.0000.000
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0000.000
Bibliometrics0.0000.001
Science and technology studies0.0000.001
Scholarly communication0.0000.000
Open science0.0000.000
Research integrity0.0000.000
Insufficient payload (model declined to judge)0.0030.001

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 head0.009
GPT teacher head0.194
Teacher spread0.185 · 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 teacher head, not a consensus.

Study designObservational
Domainnot available
GenreEmpirical

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

Citations24
Published2004
Admission routes1
Has abstractyes

Explore more

Same venueAmerican MineralogistSame topicGeological and Geochemical AnalysisFrench-language works237,207