Cretaceous (Albian to Cenomanian) biostratigraphic, paleogeographic and paleoenvironmental reconstruction of the northern Western Interior Sea: Yukon, Canada

摘要: Abstract The Eagle Plain region, located in the northeastern Yukon Territory, Canada, forms a northern segment of Cretaceous Western Interior Sea. Its preserved mid-Cretaceous strata (Whitestone River Formation and Group) document an active structural regime, sea-level fluctuations, paleoecosystem changes paleogeographic evolution south gateway to Polar This study integrates foraminiferal assemblages recovered from two wells (Molar P-34 Ellen C-24) one Late Albian bentonite age with well log signatures previously established outcrop data. proposed biostratigraphic framework correlates between both fauna observed outcrops. Three zones are recognized allowing for regional correlations; Early Gaudryina tailleuri Zone, Middle early canadensis latest Miliammina manitobensis Zone. A new 206Pb/238U 105.56 ± 0.25 Ma places upper Whitestone into Albian. Foraminiferal morphogroups their relative proportions allow paleoenvironmental reconstruction, including oxygen nutrient conditions. represents deposition fully marine, oxygenated proximal shelf setting during Albian, resulting Formation. Molar deep water, offshore increased accommodation space marked by increase tubular suspension feeders, demonstrating northwestward deepening basin. reflect widely depositional cycles Sea (Moosebar, Hulcross, Joli Fou Mowry seas). During time seas was inundated, contrasting either short lived closure or severely restricted phase Albian/Cenomanian boundary interval.