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Identification of thermal anomalies using clay mineral composition

Published online by Cambridge University Press:  09 July 2018

Y. Mathieu
Affiliation:
Institut Francais du Petrole, 4 rue Bois Preau, Rueil Malmaison 92506
B. Velde
Affiliation:
Laboratoire de Geologie, URA 1316 CNRS, Ecole Normale Superieure, 46 rue d'Ulm, 75005 Paris, France

Abstract

Analysis of the smectite content of mixed-layer illite/smectite minerals in 4 wells in the Paris Basin indicates that the sediments have not experienced the same thermal history throughout their burial history. Reconstruction of the total burial depths and thermal maxima for the sediments in the different levels of the wells indicates that the present-day depth-temperature relations reflect the existence of the same continuous sequence of diagenetic change in 2 of the wells. An empirical relation giving smectite content as a function of maximum paleotemperature was derived. A strong break in the clay mineral compositions in the upper levels of 2 wells at a third site indicated an anomaly in the diagenesis process. This break in the sequence of clay diagenetic transformation can be traced to major subvertical faults which cross-cut the wells. These anomalies are attributed to the faults which are assumed to have acted as thermal drains towards the surface, locally increasing the temperature of the sediments for a major portion of the burial history when the faults were active. Closure of the fault system coincides with the return to a normal pattern in clay diagenesis for sediments in the upper portions of the wells. It is concluded that clays may be used to trace thermal histories of sediments in a sedimentary basin.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1989

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References

Athy, L.F. (1930) Density, porosity and compaction of sedimentary rocks. AAPG Bull., 14, 1–24.Google Scholar
Heritier, F. & Villemin, J. (1971) Mise en evidence de la tectonic profonde du Basin de Paris par Texploration petroliere. Bull. Bur. Rech. Geol. Min., 1, 11–30.Google Scholar
Hoffmann, J. & Hower, J. (1979) Clay mineral assemblages as low grade metamorphic geothermometers: Applications to the thrust faulted Disturbed belt of Montana, USA. Pp. 5581 in: Aspects of Diagenesis. Soc. Econ. Pal. Min. Sp. Pub., 26.Google Scholar
Margara, K. (1976) Thickness of removed sediments, paleopressure and paleotemperature, southwestern part of Western Canada Basin. AAPG Bull., 60, 554–565.Google Scholar
Nadeau, P.H. & Reynolds, R.C. (1981) Burial contact metamorphism in the Mancos Shale. Clays Clay Miner., 29, 249–259.Google Scholar
Perrier, R. & Quiblier, J. (1974) Thickness changes in sedimentary layers during compaction history; Methods for quantitative evaluation. AAPG Bull., 58, 507–520.Google Scholar
Reynolds, R.C. (1980) Intestratified clay minerals. Pp. 249-303 in: Crystal Structures of Clays Minerals and their X-ray Identification.(Brindley, G. W. and Brown, G., editors). Mineralogical Society, London. Google Scholar
Vacquier, V., Mathieu, Y., Legendre, E. & Blondin, E. (1988) Experiment on estimating thermal conductivity of sedimentary rocks from oil well logging. Am. Ass. Petrol. Geol. Bull., 72, 758–764. Google Scholar
Velde, B. (1985a) Clay Minerals : A Physico-Chemical Explanation of their Occurrence. Elsevier, Amsterdam. Google Scholar
Velde, B. (1985b) Possible chemical controls of illite/smectite composition during diagenesis. Mineral. Mag., 49, 397–391.CrossRefGoogle Scholar
Velde, B., Suzuki, T. & Nicot, E. (1986) Pressure-Temperature-Composition relations of illite-smectite mixed layer minerals: Niger delta mudstones and other examples. Clays Clay Miner., 34, 435–441.Google Scholar
Velde, B. & Espitalie, J. (1989) Comparison of kerogen maturation and illite/smectite composition in diagenesis. J. Petrol. Geol., 12, 103–110.Google Scholar