Age and Isotopic Investigations of the Olds Ferry Terrane and its Relations to Other Terranes of the Blue Mountains Province, Eastern Oregon and West-Central Idaho
Notice bibliographique
Résumé
The Olds Ferry terrane of the Blue Mountains province is one of the numerous accreted terranes that comprise the western North American Cordillera. The Blue Mountains province is located in central and eastern Oregon, western Idaho, and extreme southeastern Washington, and is a crucial link in reconstructions of the North American Cordillera due to its position in an area with few visible terranes between the more extensively exposed terranes to the south in California and Nevada and to the north in Canada and Alaska. New field evidence and U-Pb zircon geochronology for volcanics within the sedimentary onlap assemblages overlying the Wallowa and Olds Ferry volcanic arc terranes provide evidence for an earlier connection between the terranes than has previously been recognized. The boundary between the Izee and Olds Ferry strata is an angular unconformity based on geochronological data, the consistent angular discordance between the Olds Ferry and Izee strata, and the presence of locally derived volcanic and plutonic clasts of the Olds Ferry arc in the basal Weatherby conglomerate of the Izee terrane. I correlate this unconformity with that present at the base of the transgressive fluvial-deltaic and marine sequence of the Coon Hollow Formation of the Wallowa terrane based on new ages from units bracketing this unconformity. Ages for the basal Coon Hollow and Weatherby Formations allow these to be correlative sedimentary onlap packages and thus demonstrate the connection between the Wallowa and Olds Ferry terranes by Early Jurassic time. Detailed field mapping and geochronology was used to split the Huntington Formation into two members, and establish their relationships to underlying plutonic rocks and the overlying sediments of the Izee basin onlap sequence. Geochemical data support splitting the Huntington Formation into two members, and support a model of eruption in an island-arc environment with a combination of mantle and crustal magma sources distinct from the island arc that is the Wallowa terrane. Geochronologic and structural constraints also provide evidence that Olds Ferry volcanism continued well into the Early Jurassic, and that the lower and upper members of the Huntington Formation are separated by an angular unconformity and rest with nonconformity on the underlying plutonic units. Precambrian xenocrystic zircons in lower and upper Huntington Formation volcanics indicate that the Olds Ferry terrane was proximal to cratonal North America during much of its history. Age correlations made possible by new U-Pb geochronology indicate that the Olds Ferry and Wallowa arcs may have been active concurrently in the early Late Triassic, followed by a period in the Late Triassic when the Olds Ferry arc was volcanically active while the Wallowa arc was quiescent.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,001 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,000 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».