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TitreCarboniferous and Permian reefs of Sverdrup Basin, Canadian Arctic: an aid to Barents Sea exploration
AuteurBeauchamp, B
SourceArctic geology and petroleum potential; par Vorren, T O (éd.); Bergsager, E (éd.); Dahl-Stamnes, Ø A (éd.); Holter, E (éd.); Johansen, B (éd.); Lie, E (éd.); Lund, T B (éd.); Norwegian Petroleum Society (Npf), Special Publication vol. 2, 1993 p. 217-241,
Séries alt.Commission géologique du Canada, Contributions aux publications extérieures 36991
Documentpublication en série
Mediapapier; en ligne; numérique
ProvinceNunavut; Région extracotière du nord
Sujetsrécifs fossiles; récifs; Artinskien; milieu sédimentaire; sedimentation; récifs algaires; buttes algaires; bassins; bassins sédimentaires; température de l'eau; dolomitisation; diagenèse; exploration pétrolière; Bassin de Sverdrup ; géologie marine; combustibles fossiles; Carbonifère; Permien
Résumé(disponible en anglais seulement)
Hundreds of Carboniferous and Permian reefs occur in the Sverdrup Basin, Canadian Arctic Archipelago. Reef occurrences span the Bashkirian to Artinskian time interval. There are three basic morphological types: small patch reefs, wide tabular banks, and large reef-mounds. Each type reflects the amount of space available for buildup growth in various depositional environments (inner to outer shelf, shelf-edge, slope). Biologically, Sverdrup reefs can be grouped into three broad categories: bryozoan reefs, algal reefs and mixed reefs. The three categories coexisted throughout most of the Bashkirian to Sakmarian interval, with bryozoan reefs occurring in deep water and algal reefs in shallow water; mixed reefs occupied an intermediate position. With time, the bryozoan reef belt expanded, as the algal and mixed reef belts were contracted into increasingly narrower belts against the basin margin. By Artinskian time, all niches from inner shelf to slope were occupied by bryozoan reefs. This trend parallels a major cooling trend in the Sverdrup Basin in late Paleozoic time and indicates that both temperature and water depth were the main controls on buildup types. Most Sverdrup reefs are tightly cemented by early and late diagenetic carbonate phases, but meteoric diagenesis and dolomitization led, in some cases, to a considerable porosity enhancement. The best reef prospects for oil and gas exploration are: subaerially exposed tabular banks; fault-controlled dolomitized reef-mounds; and evaporite-encased dolomitized reef-mounds.