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[1] Svalbard is an anomalous, subaerial part of the Barents Shelf, Northeast Atlantic Ocean. In this study, we performed both, one-and two-dimensional subsidence analyses based on basin structure, water depth, and thermochronology, to quantify and date the phases of uplift affecting Svalbard during the Cenozoic. Svalbard has experienced two phases of uplift, from >36 to~10 Ma, and since~10 Ma, similar in timing to uplift phases identified in Greenland, Scandinavia, and the Barents Shelf. Total uplift across much of the Central Tertiary Basin of Svalbard is >1.5 km and exceeds 2.5 km in parts of the West Spitsbergen Foldbelt (WSFB). Uplift from >36 to~10 Ma accounts for the greatest part of the vertical motion and like the younger phase reduces in magnitude towards the east. Flexural rigidity of the lithosphere is estimated to be low (Te % 5 km), so that post-36 Ma erosion of the WSFB contributes little to the uplift, whose permanent nature and proximity to the synchronous Yermak Plateau favors a link to regional magmatic underplating. Plume dynamic support and flexural unloading along the western transform plate margin can be ruled out as influences on vertical motions. Since~10 Ma renewed uplift, generating the modern topography may be linked to thermal erosion of the mantle lithosphere under Svalbard. We suggest that a likely cause of much of the surface uplift is the northward propagation of the Knipovich Ridge to establish continuous seafloor spreading through the Fram Strait after~10 Ma.

The Central Tertiary Basin (CTB) of Svalbard provides a rare opportunity for studying the sedimentary response to the Cenozoic evolution of the Barents Sea area. Here we present a basin model based on low-temperature thermochronology data, vitrinite reflectance measurements, and clay mineralogy from two drill cores inside the CTB. Our model suggests a tight relationship between the basin history and the regional geodynamic evolution. Enhanced heat flow during the Paleocene implies an extensional or transtensional origin of the basin, prior to Eurekan deformation. The first, compressional stage of the Eurekan orogeny was associated with rapid basin subsidence and high deposition rates, causing the coalification of the CTB hard coals. The second, transpressional stage of the Eurekan triggered rapid basin erosion and was associated with a decreasing heat flow. Onset of erosion is placed at ~45 ± 5 Ma, suggesting cessation of CTB deposition already by the late Early Eocene. Rapid erosion stopped coevally or just prior to the change to an extensional setting at the end of Eurekan deformation. Between ~40 and 10 Ma, the CTB experienced continuous slow erosion. From the Late Miocene onwards, erosion again accelerated, maybe related to lithospheric processes associated with northward propagation of the Knipovich Ridge. Estimates from our best-fit model suggest that nearly ~4 km of overburden was removed from the CTB since the end of Early Eocene.

Northern Svalbard represents a basement high surrounded by the Norwegian‐Greenland Sea/Fram Strait, Eurasian Basin, the Barents Shelf and the onshore Central Tertiary Basin (CTB). Published apatite fission track (AFT) data indicate Mesozoic differential, fault‐controlled uplift and exhumation of the region. Thermal history modelling of published and new AFT and (U–Th–Sm)/He ages of 51–153 Ma in the context of regional stratigraphy and geomorphology implies at least two, possibly three, uplift and exhumation stages since late Mesozoic, separated by episodes of subsidence and sediment deposition. Late Cretaceous/Palaeocene exhumation and subsequent burial appear to be related with the transition of compressional to transpressional collision of Svalbard and Greenland during the Eurekan Orogeny. Renewed exhumation since the Oligocene probably results from passive margin formation after the separation of Svalbard and Greenland, when a new offshore sedimentary basin opened west of Svalbard. Final uplift since the Miocene eventually re‐exposed the palaeosurface of northern Svalbard.

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