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TitreSource rock characterization and biostratigraphy (palynology) of Jurassic-Cretaceous strata preserved in the Hoodoo Dome H-37 oil and gas well, Ellef Ringnes Island, Sverdrup Basin n
AuteurGalloway, J M; Sweet, A R; Sanei, H; Dewing, K; Hadlari, T; Embry, A F; Swindles, G T; Reyes, J
Source39th Annual Yellowknife Geoscience Forum, abstracts; par Fischer, B J; Watson, D M; Northwest Territories Geoscience Office, Yellowknife Geoscience Forum Abstracts Volume 2011 p. 102 (Accès ouvert)
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Séries alt.Secteur des sciences de la Terre, Contribution externe 20110254
Réunion39th Annual Yellowknife Geoscience Forum; Yellowknife, NWT; CA; Nov. 15-17, 2011
Documentpublication en série
Mediapapier; en ligne; numérique
Lat/Long OENS-100.0000 -99.0000 78.2500 78.0000
Sujetsbiostratigraphie; palynologie; roches mères; pétrole; gaz; Bassin de Sverdrup ; Membre de Romulus ; Formation d'Heiberg ; paléontologie; combustibles fossiles; Mésozoïque; Crétacé; Jurassique
ProgrammeBassin sédimentaire Sverdrup, GEM : La géocartographie de l'énergie et des minéraux
Résumé(disponible en anglais seulement)
Hoodoo Dome H-37 is an oil and gas well drilled by Panarctic in 1970 adjacent to Hoodoo Dome, a salt-cored structure on southeastern Ellef Ringnes Island, Sverdrup Basin. Hoodoo Dome H-37 spudded in Cretaceous strata and intersects Romulus Member of Heiberg Formation (Late Triassic). Studied intervals within Hoodoo Dome H-37 are represented by Aalenian (Middle Jurassic) to Albian (Early Cretaceous) strata.

Cuttings samples were analyzed for Rock-Eval® 6 analysis, organic petrology, and palynology to better understand sources and maturity of organic matter and age of strata of the central Sverdrup Basin.

Total organic carbon (TOC) content of the shales, siltstones, and coals preserved in Hoodoo Dome H-37 vary from 0.84% to 6.0% (mean 2.31 ± 0.61 SD %). TOC reaches a maximum in the Walker Island Member of Isachsen Formation. Samples from the Paterson Island Member, Isachsen Formation, show high S2 values (mean 3.63 ± 0.98 SD mg HC/g rock), and consequently HI values (mean 165.07 ± 25.57 SD), compared to the whole well (mean HI 97.02 ± 57.12 SD). The majority of material preserved in Hoodoo Dome H-37 is immature (Tmax <435 °C, Ro < 0.6 %), although samples from the lower McConnell Island Formation have Tmax values between 439 and 440 °C. Tmax also exceeds 435 °C in the Paterson Island Member.

Palyno-assemblages preserved in Hoodoo Dome H-37 consist of a diversity of pollen and spore types attributable to bryophytes (mosses), lycopodiophytes, pteridophytes (ferns), and pinophytes (conifers) that change over time due to Mesozoic climate change. Q- and R-mode cluster analysis show that at least four informal palyno-assemblage zones occur. Non-metric multidimensional scaling ordination demonstrates that the assemblages fall into two main populations: Population One consists of samples from Jameson Bay, Sandy Point, McConnell Island, Ringnes, and Deer Bay Formations (Aalenian to Valanginian) while Population Two consists mainly of samples from Isachsen and Christopher Formations (Valanginian to Albian). Pteridophyte, lycopodiophyte, and bryophyte spores decline in importance in the Late Bathonian, suggesting that climate in Sverdrup Basin shifted form humid and warm to arid and warm. Expansion of Cheirolepdiaceans (indicated by Classopollis sp. pollen) indicates an increase of seasonal aridity. The largest change in palyno-flora occurred in the Late Valanginian when pollen from pinophytes, Cheirolepidaceans, and Cycadales/Ginkgoales/Bennettitales decline in abundance and are replaced by pollen attributable to Taxodiaceae-Cupressaceae-Taxaceae. Plants related to the Taxodiaceae, Cupressaceae, and/or Taxaceae may have expanded due to an increase in effective moisture and a decline in temperature. The response of vegetation in Sverdrup Basin to widespread climate changes provides a means for global correlation and identification of important biostratigraphic events.