Tectonostratigraphy and sedimentary architecture of rift basins, with reference to the northern North Sea

• Published in: Marine and petroleum geology Vol. 12; no. 8; pp. 881 - 901
• Main Authors: Nottvedt, A., Gabrielsen, R.H., Steel, R.J.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 1995; Elsevier Science
• Subjects: Applied sciences; Crude oil, natural gas and petroleum products; Energy; Exact sciences and technology; Fuels; Geophysical prospecting. Seismic methods and other methods. Exploration in boreholes. Well logging; North Sea; Prospecting and exploration; Prospecting and production of crude oil, natural gas, oil shales and tar sands; rift basins; tectonostratigraphy; North Sea; tectonostratigraphy; North Sea; rift basins; Collapse; Basin(geol); Petroleum geology; Sedimentary structure; Bending; Stratigraphy; Subsidence; Sedimentation; Tectonics
• ISSN: 0264-8172; 1873-4073
• DOI: 10.1016/0264-8172(95)98853-W

A tectonostratigraphic model for the evolution of rift basins has been built, involving three distinct stages of basin development separated by key unconformities or unconformity complexes. The architecture and signature of the sediment infill for each stage are discussed, with reference to the northern North Sea palaeorift system. The proto-rift stage describes the rift onset with either doming or flexural subsidence. In the case of early doming, a proto-rift unconformity separates this stage from the subsequent main rift stage. Active stretching and rotation of fault blocks during the rift stage is terminated by the development of the syn-rift unconformity. Where crustal separation is accomplished, a break-up unconformity commonly marks the boundary to the overlying thermal relaxation or post-rift stage. Tabular architectures, thickening across relatively steep faults, characterize the proto-rift stage. Syn-rift architectures are much more variable. Depending on the ability of the sediment supply to fill the waxing and waning accommodation created during rotation and subsidence, one-, two- or three-fold lithosome architectures are likely to develop. During the post-rift stage, an early phase with coarse clastic infilling of remnant rift topography often precedes late stage widening of the basin and filling with fine-grained sediments.