| Titre | Exploring relationships between diagenesis and thermal maturity anomalies in the Upper Devonian Duvernay Formation shale oil and gas reservoir, Alberta, Canada |
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| Auteur | Knapp, L J; Ardakani, O H ; Uchida, S |
| Source | Geoconvention 2020 abstracts; 2020 p. 1-2  Accès
ouvert |
| Liens | Online - En ligne
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| Image |  |
| Année | 2020 |
| Séries alt. | Ressources naturelles Canada, Contribution externe 20190536 |
| Éditeur | Geoconvention Partnership |
| Réunion | Geoconvention 2020; Septembre 21-23, 2020 |
| Document | site Web |
| Lang. | anglais |
| Media | en ligne; numérique |
| Formats | pdf |
| Province | Alberta |
| SNRC | 72M; 73D; 73E; 73L; 73M; 74D; 82M; 82N; 82O; 82P; 83; 84A; 84B; 84C; 84D; 93A; 93H; 93I; 93P; 94A |
| Lat/Long OENS | -120.0833 -110.0500 57.0000 51.0000 |
| Sujets | Dévonien supérieur; roches reservoirs; géologie du substratum rocheux; lithologie; roches sédimentaires; schistes; ressources pétrolières; hydrocarbures; gaz; pétrole; diagenèse; maturation thermique;
échantillons carrotés; anomalies géochimiques; porosité; contrôles structuraux; migration des hydrocarbures; carbone organique; taille des pores; perméabilité; Formation de Duvernay ; combustibles fossiles; sédimentologie; géochimie; Sciences et
technologie; Nature et environnement; Phanérozoïque; Paléozoïque; Dévonien |
| Programme | Les géosciences pour les nouvelles sources d'énergie Caractérisation des réservoirs de schiste |
| Diffusé | 2020 09 01 |
| Résumé | (Sommaire disponible en anglais seulement)
In the Duvernay Formation shale gas and oil reservoir, gas-oil ratios generally increase with depth. However as data density has increased with
continued drilling, thermal maturity and produced gas composition anomalies have been revealed (Preston et al., 2016).
This study presents preliminary observations of thermal maturity trends based on published data and analysis of hundreds of
core samples from three wells in the West Shale Basin of the Duvernay Formation. Analysis included XRD, ICP-MS, Rock-Eval 6 pyrolysis, organic petrology, reflectance measurements, FIB-SEM, helium porosimetry, H1 NMR, and MICP.
Up-dip deviations
of thermal maturity and gas composition contours occur at similar orientation to and sometimes directly overlying SW-NE trending basement structure lineaments and reef complexes, suggesting these features may have acted as conduits for heat flow
upwards into the Duvernay Formation. The similarity of gas composition and thermal maturity maps negates up-dip gas migration as the main cause of gas composition anomalies.
In some wells wide intra-well variations occur in both Tmax and bitumen
reflectance (%BRo). Covariance of Tmax and %BRo confirms that thermal maturity variations are not artifacts of low quality data. Tmax is positively correlated to biogenic silica, and drops sharply at Sequence Boundary 2 (Knapp et al., 2019),
concurrent with decreased biogenic silica, TOC, and porosity, and increased carbonates and clays. Biogenic silica sourced from radiolarian dissolution (Knapp et al., 2017) occurs as widespread microcrystalline quartz throughout the matrix, and its
concentration is not related to thermal history. Biogenic silica enhances porosity and pore size in Duvernay samples by creating a load-bearing rigid mineral framework (Knapp et al., in press). Duvernay porosity and permeability are positively
correlated (Dong et al., 2019). These observations suggest that heat may have convected laterally through strata-bound porous and permeable siliceous mudstones at some time between deposition and present day. |
| Sommaire | (Résumé en langage clair et simple, non publié)
Cette étude présente des observations préliminaires des tendances de la maturité thermique basées sur des données publiées et l'analyse de
centaines de carottes provenant de trois puits dans le bassin de schiste occidental de la formation de Duvernay. |
| GEOSCAN ID | 321810 |
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