Basin shape and sediment architecture in the Gun Supersequence: A strike‐slip model for Pb–Zn–Ag ore genesis at Mt Isa
Notice bibliographique
Résumé
Sequence‐stratigraphic correlations provide a better understanding of sediment architecture in the Mt Isa and lower McNamara Groups of northern Australia. Sediments record deposition in a marine environment on a broad southeast‐facing ramp that extended from the Murphy Inlier in the northwest to the Gorge Creek, Saint Paul and Rufous Fault Zones in the southeast. Depositional systems prograded in a southeasterly direction. Shoreline siliciclastic facies belts initially formed on the western and northern parts of the ramp, deeper water basinal facies occurred to the east and south. The general absence of shoreline facies throughout the Mt Isa Group suggests that depositional systems originally extended further to the east and probably crossed the Kalkadoon‐Leichhardt Block. Fourteen, regionally correlatable fourth‐order sequences, each with a duration of approximately one million years, are identified in the 1670–1655 Ma Gun Supersequence. Stratal correlations of fourth‐order sequences and attendant facies belts resolve a stratigraphic architecture dominated by times of paired subsidence and uplift. This architecture is most consistent with sinistral strike‐slip tectonism along north‐northeast‐oriented structures with dilational jogs along northwest structures as the primary driver for accommodation. Although reactivated during deformation, the ancestral northwest‐trending May Downs, Twenty Nine Mile, Painted Rocks, Transmitter, Redie Creek and Termite Range Fault Zones are interpreted as the principal synsedimentary growth structures. Sinistral strike‐slip resulted in a zone of long‐lived dilation to the north of the May Downs/Twenty Nine Mile and Gorge Creek Fault Zones and a major basin depocentre in the broad southeast‐facing ramp. Subordinate depocentres also developed on the northern side of the ancestral Redie Creek and Termite Range fault zones. Transfer of strike‐slip movement to the east produced restraining or compressive regions, localising areas of uplift and the generation of local unconformities. Northwest‐ and north‐northeast‐oriented magnetic anomalies to the south and west of Mt Isa, identify basement heterogeneities. Basement to the south and west of these anomalies is interpreted to mark intrabasin siliciclastic provenance areas in the Gun depositional system. Pb–Zn–Ag deposits of the Mt Isa valley are interpreted as occurring in a major basin depocentre in response to a renewed phase of paired uplift and subsidence in late Gun time (approximately 1656 Ma). This event is interpreted to have synchronously created accommodation for sediments that host the Mt Isa deposit, while focusing topographically and thermobarically driven basinal fluids into the zone of dilation.
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 | 0,001 | 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 | 0,001 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,007 | 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 ».