MétaCan
Menu
Back to cohort
Record W2294233410 · doi:10.14288/1.0053347

Anomaly in geomagnetic variations on the west coast of British Columbia

2011· article· en· W2294233410 on OpenAlexaffabout
A. Lambert

Bibliographic record

VenuecIRcle (University of British Columbia) · 2011
Typearticle
Languageen
FieldBiochemistry, Genetics and Molecular Biology
TopicGeomagnetism and Paleomagnetism Studies
Canadian institutionsUniversity of British Columbia
Fundersnot available
KeywordsEarth's magnetic fieldGeologyAnomaly (physics)West coastSouth Atlantic AnomalyClimatologyGeodesyOceanographyVan Allen radiation beltMagnetospherePhysics

Abstract

fetched live from OpenAlex

Four portable magnetometer stations were set up at intervals of 80 - 100 kilometers along an east-west profile running from Tofino on the west coast of Vancouver Island to Abbotsford on the mainland in order to study the spatial dependence of the coastal anomaly. These were supplemented by records from the permanent Victoria Magnetic Observatory. The Tofino-Abbotsford chain extends and partly overlaps an earlier chain of stations set up to search for geomagnetic anomalies, along an east-west profile from Lethbridge, Alberta to Vancouver, British Columbia, The coastal anomaly recorded at Tofino is observed exclusively in the vertical component, diminishing rapidly inland and reaching its maximum value when the inducing field changes in approximately an east-west direction with a frequency between one and two cycles per hour. The horizontal and vertical variations are in a ratio of two to one at the coast which is in agreement with induction ratios calculated at coastlines in Australia and California. The directional dependence and limited spatial extent of the anomaly indicate a rather shallow conductivity discontinuity, at most 100 kilometers deep, running approximately parallel to the continental shelfline. Since at the maximum response frequency the upper mantle beneath the ocean is largely shielded by the overlying wedge of sea water, the anomaly is thought to be mostly due to the conductivity contrast between the deep ocean and the continent. The diurnal geomagnetic variations which pass through the surface layers virtually unattenuated show at least a twenty five percent enhancement in the vertical component from Abbotsford to Tofino. This anomaly perhaps reflects a change in upper mantle conductivity more accurately than does the higher frequency Tofino anomaly. At a still higher frequency of three cycles per hour where the Tofino anomaly is already reduced, there is a small anomaly in the vertical component at Westham Island on the east side of Georgia Strait which is completely absent at lower frequencies. The influence of a shallow body of sea water such as Georgia Strait is expected to be small. Hence this anomaly is probably due to a conductivity structure beneath the Strait in the crust or upper mantle.

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)0.000
metaresearch head score (Gemma)0.001
Version: metacan-v3-hybrid-931329e0061cValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Observational · Consensus signal: Observational
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.033
Threshold uncertainty score0.067

Distilled classifier scores by category (both heads)

CategoryCodexGemma
Metaresearch0.0000.001
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0000.000
Bibliometrics0.0010.002
Science and technology studies0.0010.000
Scholarly communication0.0010.000
Open science0.0000.000
Research integrity0.0000.000
Insufficient payload (model declined to judge)0.0020.000

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 head0.160
Teacher spread0.151 · 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 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

Citations0
Published2011
Admission routes2
Has abstractyes

Explore more

Same venuecIRcle (University of British Columbia)Same topicGeomagnetism and Paleomagnetism StudiesFrench-language works237,207