Hostname: page-component-586b7cd67f-l7hp2 Total loading time: 0 Render date: 2024-11-29T14:00:03.591Z Has data issue: false hasContentIssue false
  • English
  • Français

Facies-related diagenesis in the Main Claymore Oilfield sandstones

Published online by Cambridge University Press:  09 July 2018

I. S. C. Spark  and
N. H. Trewin
I. S. C. Spark
Affiliation:
Department of Geology and Mineralogy, Marischal College, University of Aberdeen, Aberdeen AB9 1AS
N. H. Trewin
Affiliation:
Department of Geology and Mineralogy, Marischal College, University of Aberdeen, Aberdeen AB9 1AS
Get access Rights & Permissions [Opens in a new window]

Abstract

Four major sedimentary sequences of the Triassic and Upper Jurassic of the Main Claymore Oilfield of the North Sea each contain a characteristic suite of diagenetic minerals and fabrics. (1) Triassic Skagerrak Formation fluvial sandstones contain early authigenic pore-lining smectite, together with kaolinite and chlorite which form grain replacements and pore fills. Quartz and feldspar overgrowths are minor. Ferroan dolomite forms a late diagenetic patchy poikilotopic cement. Smectite is converted to illite-smectite in a 5 m thick zone beneath the sub-Jurassic unconformity. Smectite formed early in diagenesis prior to oil migration and destroyed permeability. Thus oil is not found in these sandstones although they occur in the oilzone. (2) The Piper Formation (late Oxfordian/early Kimmeridgian) paralic deposits mainly contain authigenic, pore-lining illite-smectite, vermicular kaolinite grain replacements and pore fills. Quartz overgrowths are generally well developed. (3) The Kimmeridge Clay Formation (early Kimmeridgian/early Volgian) comprises thin marine sandstone turbidites, contained within a thick siltstone/shale sequence. In the sandstones (the ‘Ten Foot Sandstone’) discrete double-ended quartz crystals (1–20 µm) developed prior to quartz, K- and Na-feldspar overgrowths. Only minor kaolinite and lllite-smectite are present. Late diagenetic dolomitic occurs as a patchy poikilotopic cement and as clusters of pore-filling rhombs. (4) The Claymore Sandstone Member (early to middle Volgian) thick marine sandstone turbidites are interbedded with thin siltstones/shales. Sandstones have well-developed quartz, K and Na-feldspar overgrowths, and kaolinite and illite-smectite occur as grain replacements and rarely as pore fills. Late-diagenetic dolomite and ferroan dolomite form poikilotopic cement and clusters of pore-filling rhombs. The major factors which control diagenetic features are depositional environment and associated porewater together with original mineralogy. Burial history and textural features of the sandstones also have important influences. Reservoir quality is controlled by a complex interplay of these features.

Type
Research Article
Information
Clay Minerals , Volume 21 , Issue 4 , October 1986 , pp. 479 - 496
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1986

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Berner, R.A. (1970) Sedimentary pyrite formation. Am. J. Sci. 268, 1–23.CrossRefGoogle Scholar
Blatt, H. (1979) Diagenetic processes in sandstones. Pp. 141–157 in: Aspects of Diagenesis (Scholle, P. A. and Schluger, P. R., editors). Soc. Econ. Palaeont. Mineral. Spec. Pub. 26.CrossRefGoogle Scholar
Boles, J.R. & Franks, S.G. (1979) Clay diagenesis in Wilcox sandstones of southwest Texas: implications of smectite diagenesis on sandstone cementation. J. Sediment. Petrol. 49, 55–70.Google Scholar
Burley, S.D. (1984) Patterns of diagenesis in the Sherwood Sandstone Group (Triassic), United Kingdom. Clay Miner. 19, 403–440.CrossRefGoogle Scholar
Bjørlykke, K. (1983) Diagenetic reactions in sandstones. Pp. 169–213 in: Sediment Diagenesis, (Parker, A. and Sellwood, B. W., editors). D. Reidel, Dordecht.CrossRefGoogle Scholar
Cant, D.J. & Walker, R.G. (1976) Development of a braided-fluvial facies model for the Devonian Battery Point Sandstone, Quebec. Can. J. Earth Sci. 13, 102–119.Google Scholar
Cant, D.J. & Walker, R.G. (1978) Fluvial processes and resulting facies sequences in the sandy braided south Saskatchewan River. Sedimentology 25, 625–648.CrossRefGoogle Scholar
Cecil, C.B. & Heald, M.T. (1971) Experimental investigation of the effects of grain coatings on quartz growth. J. Sediment. Petrol. 41, 582–584.CrossRefGoogle Scholar
Deegan, C.E. & Scull, B.J. (1977) A standard lithostratigraphic nomenclature for the central and northern North Sea: Rep. Inst. Geol. Sci. 77/25. HMSO.Google Scholar
Elliott, T. (1983) Facies, sequences and sand bodies of the principal elastic depositional environments. Pp. 1–56 in: Sediment Diagenesis (Parker, A. and Sellwood, B. W., editors). D. Reidel, Dordecht.Google Scholar
Franks, S.G. & Forester, R.W. (1984) Relationships among secondary porosity, pore-fluid chemistry and carbon dioxide, Texas Gulf Coast. Pp. 63–79 in: Clastic Diagenesis (McDonald, D. A. and Surdam, R. C., editors). Am. Ass. Petrol. Geol. Mem. 37.Google Scholar
Fuchtbauer, H. (1983) Facies controls on sandstone diagenesis. Pp. 000–000 in: Sediment Diagenesis, (Parker, A. and Sellwood, B. W., editors). D. Reidel, Dordecht.Google Scholar
Rawson, P.F. & Riley, L.A. (1982) Latest Jurassic-Early Cretaceous Events and the ‘Late Cimmerian Unconformity’ in North Sea Area. Bull. Am. Ass. Petrol Geol. 66, 2628–2648.Google Scholar
Rhys, G.H. (compiler) (1974) A proposed standard lithostratigraphic nomenclature for the Southern North Sea and an outline structural nomenclature for the whole of the (U.K.) North Sea. Rep. lnst. Geol. Sci. 74/8. HMSO.Google Scholar
Ryer, T.A. (1977) Patterns of Cretaceous shallow-marine sedimentation, Coalville and Rockport areas, Utah. Bull. Geol. Soc. Am. 88, 177–188.2.0.CO;2>CrossRefGoogle Scholar
Surdam, R.C., Boese, S.W. & Crossey, L.J. (1984) The chemistry of secondary porosity. Pp. 127–149 in: Clastic Diagenesis (McDonald, D. A. and Surdam, R. C., editors). Am. Ass. Petrol. Geol. Mem. 37.Google Scholar
Turner, C.C., Richards, P.C., Swallow, J.L. & Gaimshaw, S.P. (1984) Upper Jurassic stratigraphy and sedimentary facies in the Central Outer Moray Firth Basin, North Sea. Marine and Petroleum Geology 1, 105–117.CrossRefGoogle Scholar
Usdowsky, H.E. (1968) The formation of dolomite in sediments. Pp. 21–32 in: Recent Developments in Carbonate Sedimentology in Central Europe (Miller, G. and Friedman, G. M., editors). Springer-Verlag, Berlin.CrossRefGoogle Scholar
Velde, B. (1983) Diagenetie reactions in clays. Pp. 215–268 in: Sediment Diagenesis (Parker, A. and Sellwood, B. W., editors). D. Reidel, Dordecht.CrossRefGoogle Scholar
Waugh, B. (1970) Formation of quartz overgrowths in the Penrith Sandstone (Lower Permian) of N.W. England as revealed by scanning electron microscopy. Sedimentology 14, 309–320.CrossRefGoogle Scholar