| Titre | Overpressure detection in the Beaufort-Mackenzie Basin, northern Canada, using an integrated approach |
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| Auteur | Hu, K ; Issler, D
R; Chen, Z; Dietrich, J R; Dixon, J |
| Source | GeoConvention 2022, abstracts; 2022, 1 feuille |
| Image |  |
| Année | 2022 |
| Séries alt. | Ressources naturelles Canada, Contribution externe 20220002 |
| Réunion | GeoConvention; Calgary; CA; juin 20-22, 2022 |
| Document | livre |
| Lang. | anglais |
| Media | papier; en ligne; numérique |
| Formats | pdf |
| Province | Territoires du Nord-Ouest; Yukon |
| Région | Mer de Beaufort; Mackenzie Bay |
| Lat/Long OENS | -142.0000 -128.0000 71.5000 68.0000 |
| Sujets | Bassin de Beaufort-Mackenzie ; tectonique; Sciences et technologie; Cénozoïque; Crétacé |
| Illustrations | cartes de localisation; coupes transversales; représentations graphiques combinées; diagrammes |
| Programme | GEM : La géocartographie de l'énergie et des minéraux Corridor et delta du Mackenzie |
| Diffusé | 2022 06 20 |
| Résumé | (Sommaire disponible en anglais seulement)
The Beaufort-Mackenzie Basin (BMB) is a late Cretaceous-Cenozoic post-rift basin that is composed of a series of normally pressured and overpressured,
folded and faulted deltaic complexes. It extends northward from the onshore Mackenzie Delta to the outer shelf and slope beneath the Beaufort Sea in Arctic Canada. Overpressure is associated with rapid sediment accumulation, undercompacted shale,
shale diapirism, and major fault systems (Hitchon et al., 1990; Issler, 1992; Issler et al., 2002; Chen et al., 2010). More than 280 wells have been drilled in the basin (Fig. 1) and studies by the GSC demonstrate the strong association between
overpressure and shale porosity trends within Cenozoic strata (Fig. 2) that are detectable using multiple well logs (Issler, 1992; Katsube and Issler, 1993; Issler and Katsube, 1994; Katsube et al., 1995, 1996, 2011; Issler et al., (2002).
Previously, Issler et al. (2011) mapped the distribution of overpressure at well locations using fluid pressure and shale log data. This study focuses on overpressure detection in the Beaufort-Mackenzie Basin by employing an integrated approach that
combines geophysical, drilling, and well testing data from petroleum exploration wells. It not only presents detailed documentation of the large comprehensive datasets and refined interpretations for the top of the overpressure zone in exploration
wells (Hu et al., 2021), but it also presents stratigraphic frameworks to illustrate the distributions of the detected overpressure along schematic stratigraphic cross sections throughout the basin. One hundred and fifty-two depths to the top of
overpressure were determined for 112 wells based on the integrated analysis of the proposed multiparameter data (well logs, well seismic interval velocity, mud weight, and pressure test), most of which were confirmed by formation pressure tests, and
the overpressure interpretations were ranked according to a quality assessment scheme. Overall, well logs and log-derived formation properties in shale sections are good indicators of overpressure. However, the most reliable and consistent
geophysical parameters for detecting overpressure are shale sonic transit-time (and its porosity) and continuous sonic velocity because of the abundance of these data and the sensitivity of rock acoustic properties to porosity and stress. In general,
mud pressure trends calculated from drilling mud weight data are mostly consistent with overpressure interpretations from geophysical data and fluid pressure measurements. The interpreted depth to the top of overpressure varies from <1000 to over
4500 m (GL/SL) and is largely confined to undercompacted sediments in the central-northern delta and offshore areas. The top of overpressure is predominantly restricted to the Paleocene-Eocene Aklak, Taglu and Richards sequences on Richards Island,
and occurs in progressively younger strata northward in the offshore toward the outer shelf. In the central shelf region, the top of overpressure is mainly within the Richards and Kugmallit sequences, while it rises above the base of the thick
Pliocene-Pleistocene Iperk Sequence in the outer shelf. |
| Sommaire | (Résumé en langage clair et simple, non publié)
Cette étude se concentre sur la détection de surpression dans le bassin Beaufort-Mackenzie en utilisant une approche intégrée qui combine des
données géophysiques, de forage et d'essai de puits provenant de puits d'exploration pétrolière. Il présente non seulement une documentation détaillée des grands ensembles de données complets et des interprétations raffinées pour le sommet de la zone
de surpression dans les puits d'exploration, mais il présente également des cadres stratigraphiques pour illustrer les distributions de la surpression détectée le long d'une stratigraphie schématique. coupes transversales dans tout le
bassin. |
| GEOSCAN ID | 329897 |
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