When do faults in sedimentary basins leak? Stress and deformation in sedimentary basins; examples from the North Sea and Haltenbanken, offshore Norway

AAPG Bulletin ◽  
2005 ◽  
Vol 89 (8) ◽  
pp. 1019-1031 ◽  
Author(s):  
Knut Bjørlykke ◽  
Kaare Høeg ◽  
Jan Inge Faleide ◽  
Jens Jahren
2002 ◽  
Vol 19 (5) ◽  
pp. 519-526 ◽  
Author(s):  
Gabriela Fernández Viejo ◽  
Mireille Laigle ◽  
César R Ranero

1991 ◽  
Vol 14 (1) ◽  
pp. 9-18 ◽  
Author(s):  
Stewart Brown

The petroliferous sedimentary basins of the UK Continental Shelf are remarkable for the diversity of their reservoir strata. Reservoir rocks in fields currently in production range in age from Devonian to earliest Eocene, but significant hydrocarbon discoveries have also been made in rocks as as young as the mid-Eocene. The reservoirs are predominantly siliciclastic rocks, with facies ranging from continental fluvial and aeolian, to marine gravity flow deposits from sub-wave base environments.In this paper stratigraphic context of the producing horizons in the UK Continental Shelf (UKCS), principally the North Sea, is reviewed, and the sedimentation of the reservoir strata placed in an outline geological history. The main producing horizons are described in summary. Matters of stratigraphic terminology and correlation both between fields and between basins are discussed.A lithostratigraphy for the UK southern North Sea was established by Rhys (1974), and for the central and northern North Sea by Deegan & Scull (1977). Although these schemes have proved to be fairly robust, in the last 13 years the acquisition of new data plus a proliferation of new terms not fully documented in the public domain, argue strongly for a comprehensive revision and rationalization which is beyond the scope of this paper. Attempts in the public domain to standardize nomenclature across international boundaries in the North Sea, pursued by Deegan & Scull (1977) for the UK and Norwegian sectors, have lapsed for the most part in subsequent years.Economic basement in the UK North Sea can be regarded at present


2021 ◽  
Vol 11 (4) ◽  
pp. 1621-1642
Author(s):  
Ivanka Orozova-Bekkevold ◽  
Thomas Guldborg Petersen

AbstractOne of the most widespread hypotheses for the origin of the present-day overpressure in the shale Post-Chalk section in the North Sea is the very rapid sedimentation from Neogene to present day. We tested this hypothesis by the means of numerical forward finite elements modelling and successfully simulated the overpressure build-up during the Cenozoic filling of the North Sea with relatively simple model set-up. Our model shows that overpressure of approximately 28% above hydrostatic developed in the Neogene, while during the Quaternary, it reached up to 36% above hydrostatic. At present day, the predicted onset of overpressure starts at about 800–1000 m below seafloor, while the maximum (magnitude about 1.36 sg, i.e. 36% above the normal hydrostatic pressure) is at approximately 2100 m. This overpressure profile fits reasonably well with data from wells drilled in the Central Graben. The exact magnitude of the overpressure depends on the used assumptions, the model set-up and the values of the input parameters. Especially the dynamic interaction between high sedimentation rates, clay permeability and low horizontal pressure gradient seems to be a key factor in the efficiency of dewatering of saturated clays during burial. The results indicate that, the assumption of horizontal stress isotropy results in nearly no horizontal fluid flow, despite the same magnitude for the vertical and the horizontal permeability. In these conditions, the vertical permeability plays much bigger role than the horizontal one in the effective de-watering of the sediments during burial. Further investigation is needed to explore the role of horizontal pressure gradient in fluid migration in passive sedimentary basins.


Clay Minerals ◽  
1998 ◽  
Vol 33 (1) ◽  
pp. 15-34 ◽  
Author(s):  
K. Bjørlykke

AbstractDissolution of feldspar and mica and precipitation of kaolinite require a through flow of meteoric water to remove cations such as Na+ and K+ and silica. Compaction driven pore-water flow is in most cases too slow to be significant in terms of transport of solids. The very low solubility of A1 suggests that precipitation of new authigenic clay minerals requires unstable Al-bearing precursor minerals. Chlorite may form diagenetically from smectite and from kaolinite when a source of Fe and Mg is present. In the North Sea Basin, the main phase of illite precipitation reducing the quality of Jurassic reservoirs occurs at depths close to 4 km (130-140°C) but the amount of illite depends on the presence of both kaolinite and K-feldspar. Clay mineral reactions in shales and sandstones are very important factors determining mechanical and chemical compaction and are thus critical for realistic basin modelling.


Sign in / Sign up

Export Citation Format

Share Document