Sverdrup basin is large (~520,000 sq km) and deep (~13 km), and was long lived (Early Carboniferous to latest Cretaceous). It belongs to a distinctive class of cratonic basins because it received great volumes of terrigenous clastic sediments, but never had a contemporaneous adjacent orogenic belt. Therefore, its stratigraphic record portrays responses to cratonic epeirogenesis unmasked by eccentricities of local orogeny.

Initial subsidence of the basin (Early Carboniferous) was along a system of grabens. During Carboniferous and Permian times, the axial region was relatively starved, whereas thick carbonate deposits and sandstones accumulated on the margins. In the Triassic the axial region received great thicknesses of fine-grained terrigenous clastics but basin-margin successions were thinner and coarser grained. Jurassic and early Neocomian deposits accumulated slowly. Aptian and later Cretaceous marine and nonmarine clastic deposits transgressed widely cratonward over the formerly well-defined basinal margins, and the structural basin lost identity in a broad continental-shelf and coastal-plain complex that existed until the area was fragmented in latest Cretaceous and early Tertiary time.

Mafic volcanism in the Carboniferous, Permian, Early and Late Cretaceous, and gabbro intrusion in the Jurassic and Cretaceous, indicate that crustal fracturing, accompanied by tapping of upper mantle fluids fashioned primary basin subsidence. Sedimentation in phases of accelerated subsidence appears to be dictated by the availability of detritus and the prevailing erosional gradient on the adjacent craton. The basin was relatively starved in the Carboniferous and Permian and relatively "stuffed" in the Triassic. Thick, widely distributed sandstones indicate vigorous erosion of the craton in the intervals late Norian to Sinemurian, late Valanginian to early Aptian, late Albian to Cenomanian, and late Campanian to early Tertiary. In contrast, black, laminated, marine shales mark early p ases of marine transgression onto the craton in Leonardian, Griesbachian, Oxfordian, Valanginian, middle Albian, and Cenomanian-Turonian times.

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