Geochemical and Nd isotopic evidence for sedimentary-source changes in the Devonian miogeocline of the southern Canadian Cordillera
Bibliographic record
Abstract
Research Article| April 01, 2000 Geochemical and Nd isotopic evidence for sedimentary-source changes in the Devonian miogeocline of the southern Canadian Cordillera Ross K. Stevenson; Ross K. Stevenson 1GEOTOP and Département des Sciences de la Terre, Université du Québec à Montréal, P.O. Box 888 St. C.V., Montréal, Québec H3C 3P8, Canada Search for other works by this author on: GSW Google Scholar Steve Whittaker; Steve Whittaker 2Department of Earth and Planetary Sciences, McGill University, 3450 University Street, Montréal, Québec H3A 2A7, Canada Search for other works by this author on: GSW Google Scholar Eric W. Mountjoy Eric W. Mountjoy 2Department of Earth and Planetary Sciences, McGill University, 3450 University Street, Montréal, Québec H3A 2A7, Canada Search for other works by this author on: GSW Google Scholar GSA Bulletin (2000) 112 (4): 531–539. https://doi.org/10.1130/0016-7606(2000)112<531:GANIEF>2.0.CO;2 Article history received: 14 Aug 1998 rev-recd: 10 Jun 1999 accepted: 23 Jun 1999 first online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Ross K. Stevenson, Steve Whittaker, Eric W. Mountjoy; Geochemical and Nd isotopic evidence for sedimentary-source changes in the Devonian miogeocline of the southern Canadian Cordillera. GSA Bulletin 2000;; 112 (4): 531–539. doi: https://doi.org/10.1130/0016-7606(2000)112<531:GANIEF>2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract Sedimentological evidence indicates that clastic sediments of the Western Canada Sedimentary Basin were derived predominantly from the north and east, an exception being the westerly sourced Sassenach Formation in the Upper Devonian. A comparison of geochemical and Sm-Nd isotopic data of the Sassenach Formation and the underlying Perdrix and Mount Hawk Formations, which have easterly sources, support a change in sedimentary provenance. The Frasnian Perdrix and Mount Hawk Formations have initial ϵNd values of −7 to −8.5. This range of values is higher than that of the underlying Precambrian basement and reflects a mixture of older and younger crustal detritus (Late Proterozoic to Devonian) eroded and transported from orogens in the Arctic. The overlying Famennian Sassenach Formation yields lower initial ϵNd values that decrease from as high as −8.5 at the base to about −11 near the top. The lower ϵNd values of the Sassenach Formation imply that the western crustal source of the Sassenach sediments was, on average, older than the eastern crustal sources of the underlying formations. This older western source appears to be related to uplift and reworking of older miogeosynclinal sediments in the west as a result of compression related to the Antler orogeny. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.
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 imitationNot 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.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.003 | 0.004 |
| Science and technology studies | 0.002 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.004 | 0.000 |
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.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
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".