Anatomy and Evolution of a Slope Channel-Complex Set (Neoproterozoic Isaac Formation, Windermere Supergroup, Southern Canadian Cordillera): Implications for Reservoir Characterization
Notice bibliographique
Résumé
Abstract A detailed architectural analysis was conducted in Isaac Unit 5 of the Isaac Formation in the Castle Creek area (east-central B.C., Canada). Isaac Unit 5 developed within a turbidite-dominated slope system on the Neoproterozoic passive margin of western North America where sediment gravity flows and mass movements were common. Isaac Unit 5 crops out over a 3.5-km-long section oriented oblique to mean paleoflow direction and represents a long-lived pathway for transport and deposition that accumulated ~ 100 m of mostly sand in a deep-marine slope setting. It consists of three stacked, high net-to-gross channel-complex fills (8–30 m thick) that correspond to shorter-term flow conduits, which, in turn, are capped by mudstone-rich units. Fine-grained conglomerate and sandstone beds deposited from high-concentration sediment flows constitute most of channel-complex fills. In addition, muddy debrite and slump deposits occur, but although laterally extensive, are volumetrically minor. Laterally persistent, thin-bedded strata (4–20 m thick) composed mostly of Bouma Tc–e turbidites occur at the top of each channel complex and indicate episodes of local complex abandonment (interchannel complex deposition). Different kinds of channel-fill elements were identified within Isaac Unit 5, each characterized by a unique combination of facies assemblage, internal geometry, and bounding surfaces. Most commonly, channel fills consist of amalgamated, thick-bedded, normally graded sandstone (Bouma Ta and Tab divisions) associated with backfilling processes. Poorly stratified mudstone-clast breccia, associated with Ta beds and dune cross-stratified sandstones occur in channel fills that exhibit aggradational and laterally migrating stacking patterns. Inner-bend levee deposits are associated with this type of channel fill. Channel fills with inclined sandstone- and mudstone-rich strata, on the other hand, relate to non-aggradational, high-sinuosity channel conditions that developed during gradual abandonment of the pathways for coarse-sediment transport. In contrast, sudden deactivation of these pathways, most probably related to abrupt updip channel avulsion, led to accumulation of structureless sandstone passively filling the deactivated thalweg. In terms of hydrocarbon reservoir analogues, each of the five different channel-fill elements have unique reservoir attributes (connectivity and continuity), amalgamated and poorly stratified elements having the best (excellent to good) reservoir attributes. Due to high amalgamation at channel-fill scale, channel complexes would represent individual fluid-flow units where only laterally discontinuous permeability barriers (< 500 m long) are present. On the other hand, extensive thin-bedded elements and muddy debrites constitute kilometer-scale barrier-type facies that would effectively compartmentalize channel complexes within the channel-complex set. Strata of Isaac Unit 5 document the detailed stratigraphic complexity, evolution, and reservoir characterization that can be expected in turbidite-dominated slope channel systems developed on passive margins. Further, it is a potential analogue for similar systems developed in continent-margin basins that until now were known mostly from subsurface core and seismic data.
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 machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| 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 | 0,003 | 0,003 |
| Études des sciences et des technologies | 0,002 | 0,001 |
| Communication savante | 0,001 | 0,000 |
| Science ouverte | 0,001 | 0,001 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,002 | 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 source (Gemma direct ou Codex distillé), 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 ».