Uplift, deflation and marine onlap of a Jurassic rift dome, illustrated by a backstepping Middle-Upper Jurassic shelf-to- slope succession, Geographical Society O, East Greenland

"Doming- rifting- spreading" constitute the main phases of classical plate tectonics. The Middle- Upper Jurassic succession of East Greenland is interpreted as reflecting formation, deflation and onlap of a rift dome, similar to contemporaneous rift domes in the North Sea, Denmark and southern Sweden. The succession forms a northwards backstepping and onlapping early rift succession in the N- S oriented basin. Deposition ranged from coastal over shallow marine and slope sands, through offshore siltstones to deep basinal mudstones. An outlier on the island Geographical Society O fills an important gap in the documentation of the doming, deflation and progressive onlap. Bajocian deposition took place in a shallow marine shelf. This was followed in the late Oxfordian by slope and base-of- slope deposition. The backstepping succession onlaps progressively older rocks towards the north, illustrating the gradual deflation, erosion and onlap of the dome, constituting the early part of the doming- rifting- spreading phases of classical plate tectonics.