Transgressive–regressive (T–R) sequence analysis of the Jurassic succession of the Sverdrup Basin, Canadian Arctic Archipelago
Transgressive–regressive (T–R) sequence analysis has been applied to the Jurassic succession of the Sverdrup Basin with sequence boundaries drawn at subaerial unconformities or the correlative transgressive surfaces. A hierarchal system of sequence order that reflects the different nature of the boundaries has been formulated on the basis of boundary characteristics. Second- through fifth-order sequences have been recognized in the Jurassic succession, which itself is part of a first-order sequence of mid-Permian – Early Cretaceous age.The Jurassic strata occur within four second-order sequences. The boundaries of these sequences are characterized by widespread subaerial unconformities across which major changes in depositional and subsidence regimes occur. These boundaries are earliest Rhaetian, earliest Pliensbachian, earliest Bajocian, earliest Oxfordian, and Hauterivian in age.Each second-order sequence is divisible into a number of third-order sequences bounded mainly by basin-wide transgressive surf...