Titre | Occurrence and preservation of primary organic matter in a hybrid unconventional reservoir: Montney Formation, Western Canada Sedimentary Basin |
| |
Auteur | Haeri Ardakani, O ; Cesar, J ; Pedersen, P K ; Mackie, S J; Reyes, J ; Wood, J M |
Source | International Journal of Coal Geology vol. 261, 104096, 2022 p. 1-20, https://doi.org/10.1016/j.coal.2022.104096 |
Image |  |
Année | 2022 |
Séries alt. | Ressources naturelles Canada, Contribution externe 20220034 |
Éditeur | Elsevier |
Document | publication en série |
Lang. | anglais |
DOI | https://doi.org/10.1016/j.coal.2022.104096 |
Media | papier; numérique; en ligne |
Formats | pdf; html |
Province | Alberta; Colombie-Britannique |
Lat/Long OENS | -126.0000 -110.0000 61.0000 49.0000 |
Sujets | bassins sédimentaires; carbone; Formation de Montney ; Sciences et technologie; Nature et environnement; sédimentologie; combustibles fossiles; géochimie |
Illustrations | cartes de localisation; diagrammes; photographies; tableaux; représentations graphiques combinées |
Programme | Les géosciences de l'énergie Ressources d'énergie propre - réduire les risques environnementaux |
Diffusé | 2022 08 28 |
Résumé | (disponible en anglais seulement) The Lower Triassic Montney Formation of the Western Canada Sedimentary Basin (WCSB) is a world-class unconventional hydrocarbon resource in North America. It
was deposited on the northwestern margin of Pangaea at mid-latitudes in an arid climate and after major mass extinction at the Late Permian-Triassic boundary. Despite decades of exploration and economic importance, the origin of organic matter
composition and source of accumulated hydrocarbons is not well understood. The Montney Formation is primarily composed of dolomitic siltstone with a mean total organic carbon (TOC) content of = 1 wt. %. In this study, we re-examined samples from an
Alberta Geological Survey (AGS) data release in 2010 on Montney Formation organic petrography and expand the sampling and analysis to further investigate organic matter type, thermal maturity, and possible internal hydrocarbon source intervals within
the Montney Formation by integrating programmed pyrolysis, organic petrography, and molecular geochemistry. Organic petrography and molecular geochemistry show that millimeter to centimeter thick mudstone intervals with TOC = 1 wt. %, are dominantly
comprised of Type II marine kerogen (Prasinophyte and Tasmanites) with minimal terrigenous organic matter. The presence of these organic-rich mudstone beds in central and western Alberta reveal intra-formational sources of hydrocarbons within the
Montney Formation, in addition to hydrocarbons sourced from overlying organic-rich source rocks (i.e., Triassic Doig and Jurassic Gordondale). These results confirm that the Montney Formation in Alberta can be considered as a hybrid unconventional
hydrocarbon reservoir with an interbedded source and reservoir. Molecular geochemistry data suggest that photic zone euxinia (PZE) was favorable for the preservation of organic matter during deposition of the Montney Formation. However, in many
instances, this only happened during very short periods similar to depositional conditions on the offshore present day Namibian shelf. Traces of terrigenous organic matter were able to reach the basin, likely in the form of inertinite and
combustion-derived polycyclic aromatic hydrocarbons (PAHs). Although the results of this study show there are source rock intervals within the Montney Formation, a comprehensive organic petrography and geochemistry study on a series of full-length
Montney cores throughout the basin will help to ascertain the major paleodepositional variation and their effect on organic matter preservation as well as hydrocarbon source intervals and their contribution to WCSB petroleum systems. |
Sommaire | (Résumé en langage clair et simple, non publié) L'origine de la matière organique et des hydrocarbures dans la formation de Montney, la prolifique ressource non conventionnelle, dans le bassin
sédimentaire de l'Ouest canadien, fait l'objet d'un long débat. Cette étude examine l'origine et la composition de la matière organique dans la formation de Montney et son environnement paléodépositionnel en utilisant l'héritage de Rock-Eval6 TM
ainsi que des données nouvellement recueillies par pyrolyse programmée, géochimie moléculaire, pétrographie organique et microscopie à fluorescence. |
GEOSCAN ID | 329987 |
|
|