Early Cenozoic sedimentation in the Hammerfest Basin

Abstract

Using seismic stratigraphy combined with information from 24 wells, a detailed history of the early Cenozoic sedimentation of the Hammerfest Basin in the southwestern Barents Sea has been revealed. During the early Paleocene the Hammerfest Basin was subject to non-deposition or minor erosion, and sedimentation in the basin was initiated after a transgression in the mid-Paleocene. Coeval erosion on the basin margin ceased as the transgression gradually spread in the late Paleocene, and a south-southwesterly sediment input from the Loppa High to the Hammerfest Basin was initiated during the late Paleocene. The late Paleocene/early Eocene environment was dominated by SSW-directed progradation from the Loppa High and westward progradation in the central part of the basin. The early Tertiary sedimentation of the Hammerfest Basin is speculated as mirroring reactivation of older fault regimes, and transpression and transtension along the western margin during the latest phase of rifting and earliest phase of spreading in the Norwegian-Greenland Sea are indicated. Mid-Eocene to Pliocene sediments have not been found in the Hammerfest Basin. It seems, however, that sedimentation continued in the basin in post-early Eocene time. During the Oligocene and Miocene accumulation and erosion alternated in the Hammerfest Basin. The erosion increased during the late Miocene and Pliocene and culminated with the Pleistocene glaciations.