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Origin of pore-lining chlorite in the aeolian Rotliegend of northern Germany

Published online by Cambridge University Press:  09 July 2018

S. Hillier
Affiliation:
Geologisches Institut, Universität Bern, Baltzerstrasse 1, 3012, Switzerland
A. E. Fallick
Affiliation:
Isotope Geosciences Unit, Scottish Universities Research and Reactor Centre, East Kilbride, Glasgow, G75 0QU, Scotland
A. Matter
Affiliation:
Geologisches Institut, Universität Bern, Baltzerstrasse 1, 3012, Switzerland

Abstract

Pore-lining chlorite is common in Rotliegend lake shoreline aeolian sandstones from northern Germany and preserves abnormally high primary intergranular porosity. In the north of the study area, in a basinward direction, the chlorites are Mg-rich while towards the south they become Fe-rich over a distance of about 15 km. All are unusually rich in Mn. Magnesium-rich examples tend to be more abundant than illite, while Fe-rich examples cover framework grains less continuously and are admixed with more abundant illite. Oxygen isotope analysis of 30 chlorites in the 2–6 µm fraction gave δ18O (SMOW) values of 7 to 12‰ (mean 9.8‰). These data show no obvious trend across the study area, nor in relation to changes in chlorite composition, or burial depth.

The honeycomb arrangement of chlorite crystals suggests chlorite formation via the sequence smectite-corrensite-chlorite. Chlorite distribution and the systematic changes in its composition suggest that formation of a precursor was related to lateral migration of Mg-rich fluids from basinal shales and/or evaporites during shallow burial. Interaction of these fluids with early formed oxyhydroxide coatings on the aeolian sand grains provided a source of Fe and the Mn. The isotope data suggest that the eventual formation of chlorite during deep burial occurred from waters with positive δ18O values, comparable to those present during the deep burial formation of illite.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1996

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References

Bailey, S.W. (1988) Chlorites: structures and crystal chemistry. Pp. 347–404 in: Hydrous Phyllosilicates (exclusive of micas) (Bailey, S.W., editor) Reviews in Mineralogy, 19. Mineralogical Society of America.CrossRefGoogle Scholar
Brindley, G.W. (1961) Chlorite minerals. Pp. 242-296 in: The X-ray Identification and Crystal Structures of Clay Minerals (Brown, G., editor). Mineralogical Society, London.Google Scholar
Borthwick, J. & Harmon, R.S. (1982) A note regarding CIF2 as an alternative to BrF5 for oxygen isotope analysis. Geochim. Cosmochim. Acta, 46, 16651668.CrossRefGoogle Scholar
Clayton, R.N. & Mayeda, T.K. (1963) The use of bromine pentafluoride in the extraction of oxygen from oxides and silicates for isotopic analyses. Geochim. Cosmochim. Acta, 27, 43–52.CrossRefGoogle Scholar
COLE, (1985) A preliminary evaluation of oxygen isotopic exchange between chlorite and water. Geol. Soc. Am. Abstr. Programs, 17, 550.Google Scholar
Dixon, S.A., Summers, D.M. & Surdam, R.C. (1989) Diagenesis and preservation of porosity in Norphlet Formation (Upper Jurassic), southern Alabama. Am. Assoc. Pet. Geol. Bull. 73, 707728.Google Scholar
Fallick, A.E., Macaulay, C.I. & Haszeldine, R.S. (1993) Implications of linearly correlated oxygen and hydrogen isotopic compositions for kaolinite and illite in the Magnus Sandstone, North Sea. Clays Clay Miner. 41, 184190.CrossRefGoogle Scholar
Friedman, I. & Smlth, R.L. (1958) The deuterium content of water in some volcanic glasses. Geochim. Cosmochim. Acta, 15, 218228.CrossRefGoogle Scholar
Gast, R.E. (1991) The perennial Rofliegend saline lake in NW Germany. Geol. Jb. All9, 2559.Google Scholar
Gaupp, R., Matfer, A., Platt, J., Ramseyer, K. & Walzebuck, J. (1993) Diagenesis and fluid evolution of deeply buried Permian (Rotliegende) Gas Reservoirs, Northwest Germany. Am. Assoc. Petrol. Geol. Bull. 77, 11111128.Google Scholar
Glennie, K.W. (1990) Introduction to the Petroleum Geology of the North Sea (Glennie, K.W., editor). 3rd edition. Blackwell Scientific Publications, Oxford.Google Scholar
Hillier, S. (1993) Origin, diagenesis, and mineralogy of chlorite minerals in Devonian lacustrine mudrocks, Orcadian Basin, Scotland. Clays Clay Miner. 41, 240259.CrossRefGoogle Scholar
Hillier, S. (1994) Pore-lining chlorites in siliciclastic reservoir sandstones: electron microprobe, SEM and XRD data, and implications for their origin. Clay Miner. 29, 665679.CrossRefGoogle Scholar
Hillier, S. & Velde, B. (1991) Octahedral occupancy and the chemical composition of diagenetic (lowtemperature) chlorites. Clay Miner. 26, 149–168.CrossRefGoogle Scholar
Hogg, A.J.C., Pearson, M.J. & Fallick, A.E. (1993) Pretreatment of Fithian illite for oxygen isotope analysis. Clay Miner. 28, 149152.Google Scholar
Kugler, R.L. & Mchugh, A. (1990) Regional diagenetic variation in Norphlet Sandstone: implications for reservoir quality and the origin of porosity. Trans. Gulf Coast Assoc. Geol. Soc. 40, 411423.Google Scholar
Lee, M., Aronson, J.L. & Savin, S.M. (1989) Timing and conditions of Permian Rotliegende sandstone diagenesis, southern North Sea: K/At and oxygen isotopic data. Am. Assoc. Petrol. Geol. Bull. 73, 195215.Google Scholar
Mehra, O.P. & Jackson, M.L. (1960) Iron oxide removal from soils and clays by a dithionite-citrate system buffered with sodium bicarbonate. Clays Clay Miner. 7, 317327.CrossRefGoogle Scholar
Orhan, H. (1992) Importance of dust storms in the diagenesis of sandstones: a case study, Entrada sandstone in the Ghost Ranch area, New Mexico, USA. Sed. Geol. 77, 111-122.Google Scholar
Platt, J.D. (1993) Controls on clay mineral distribution and chemistry in the early Permian Rotliegend of Germany. Clay Miner. 28, 393416.CrossRefGoogle Scholar
Platt, J.D. (1994) Geochemical evolution of pore waters in the Rotliegend (Early Permian) of northern Germany. Mar. Pet. Geol. 11, 6678.CrossRefGoogle Scholar
Robinson, A.G., Coleman, M.L. & Gluvas, J.G. (1993) The age of illite cement growth, Village Fields area, southern North Sea: Evidence from K-Ar ages and t80/160 ratios. Am. Assoc. Petrol. Geol. Bull. 77, 6880.Google Scholar
Rossel, N.C. (1982) Clay mineral diagenesis in Rotliegend aeolian sediments of the southern North Sea. Clay Miner. 17, 6977.CrossRefGoogle Scholar
Russel, J.D., Bmnm, A. & Fraser, A.R. (1984) High gradient magnetic separation in soil clay mineral studies. Clay Miner. 19, 771778.CrossRefGoogle Scholar
Savin, S.M. & Lee, M. (1988) Isotopic studies of phyllosilicates. Pp. 189-224 in: Hydrous PhyUosilicates (exclusive of micas) (Bailey, S.W., editor). Reviews in Mineralogy 19, Mineralogical Society of America.Google Scholar
Walker, J.R. (1993) Chlorite polytype geothermometry. Clays Clay Miner. 41, 260267.CrossRefGoogle Scholar
Warren, E. & Curtis, C. (1989) The chemical composition of authigenic illite within two sandstone reservoirs as analysed by ATEM. Clay Miner. 24, 137156.CrossRefGoogle Scholar
Whitney, G. & Velde, B. (1993) Changes in particle morphology during illitization: an experimental study. Clays Clay Miner. 41, 209218.Google Scholar
Wilson, M.D. (1992) Inherited grain-rimming clays in sandstones from eolian and shelf environments: their origin and control on reservoir properties. In: Origin, Diagenesis, and Petrophysics of Clay Minerals in Sandstones (Houseknecht, D.W. & Pittman, E.D., editors). SEPM (Society for Sedimentary Geology) Spec. Pub. 47.Google Scholar
Winspear, N.R. & Pve, K. (1995) The origin and significance of boxwork clay coatings on dune sand grains from the Nebraska Sand Hills, USA. Sed. Geol. 94, 245254.CrossRefGoogle Scholar
Ziegler, K., Sellwood, B.W. & Fallick, A.E, (1994) Radiogenic and stable isotope evidence for the age and origin of anthigenic illites in the Rotliegend, southern North Sea. Clay Miner. 29, 555565.CrossRefGoogle Scholar