This PhD thesis addresses how fault and fold growth affect accommodation development and sediment routing and fill in extensional basins. Extensional basins are key constituents of passive continental passive and intra-continental rift systems and hold great potential accumulation of reservoir-grade successions of sediments. These types of basins differ widely in terms of e.g. fault and fold properties, duration of faulting, accommodation development, tectono-climatic setting and lithology of basin substrate and fill. Accordingly, constructing general models for extensional basin evolution is challenging. Combining different types of datasets that offer different observation scale and resolution can mitigate this. This thesis presents seismic case studies from the Fingerdjupet Subbasin, southwestern Barents Sea and outcrop studies from the Bandar Jissah Basin, northeastern Oman. Seismic analyses include interpretations of faults and horizons bounding seismic reflector packages; age control was achieved

No abstract

Based on a methodic sedimentological analysis, the Late Jurassic (Oxfordian) Curtis Formation unravels the intricate facies variability which occurs in a tide-dominated, fluvially starved, low-gradient, semi-enclosed epicontinental basin. This unit crops out in east-central Utah, between the eolian deposits of the underlying Middle Jurassic (Callovian) Entrada Sandstone, from which it is separated by the J-3 unconformity, and the conformable overlying supratidal Summerville Formation of Oxfordian age. A high-resolution sedimentary analysis of the succession led to the recognition of eight facies associations (FA) with six sub-facies associa­tions. Based on the specific three-dimensional arrangement of these eight facies associations, it is proposed to separate the Curtis Formation into three sub-units: the lower, middle and upper Curtis. The J-3 unconformity defines the base of the lower Curtis, which consists of upper shoreface to beach deposits (FA 2), mud-domi­nated (FA 3a) and sand-dominated heterolithic subtidal flat (FA 3b), sand-rich sub- to supratidal flat (FA 4a) and correlative tidal channel infill (FA 4c). It is capped by the middle Curtis, which coincides with the sub- to intertidal channel-dune-flat complex of FA 5, and its lower boundary corresponds to a transgressive surface of regional extent, identified as the Major Transgressive Surface (MTS). This surface suggests a potential correla­tion between the middle and the upper Curtis and the neighboring Todilto Member of the Wanakah Forma­tion or Todilto Formation. The upper Curtis consists of the heterolithic upper sub- to intertidal flat (FA 6) and coastal dry eolian dunes belonging to the Moab Member of the Curtis Formation (FA 7), and it conformably overlies the middle Curtis.

No abstract

No abstract

No abstract

When, in March 2011, I entered the building of the University Centre in Svalbard (UNIS) my first thought was:"I want to work here". This dream came true only a year later when I started my long but very rewarding journey through the PhD project. Firstly, I would like to thank my supervisor Snorre Olaussen for offered chance to develop this exciting project in Arctic rift basin geology, his patience and trust. Transition from research conducted in structural geology of metamorphic rocks to basin analysis was not easy and Snorre always served with the guidance, help and tutoring. Huge acknowledgments go to Alvar Braathen, who has introduced me to the outcrops of Billefjorden and Edgeøya, and always offered great support and advice. William Helland Hansen and Jan Inge Faleide are acknowledged for their supervision on the project. I strongly appreciate the scientific freedom and multiple possibilities for development and collaboration I had during the research.

No abstract