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The Precambrian–Cambrian boundary problem: magnetostratigraphy of the Amadeus Basin, Central Australia

Published online by Cambridge University Press:  01 May 2009

J. L. Kirschvink
J. L. Kirschvink
Affiliation:
Division of Geological and Geophysical Sciences, Princeton University, Princeton, N.J., U.S.A. Research School of Earth Sciences, The Australian National University, Canberra, A.C.T., Australia
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Summary

A magnetostratigraphic study of Upper Proterozoic to early Cambrian sediments at 4 localities in Central Australia reveals the presence of a magnetic polarity pattern composed of 2 long quiet intervals, first of reversed then of normal polarity, which is then succeeded by a long mixed interval. Lithologic comparisons suggest that this pattern is a reflection of the behaviour of the geomagnetic field at that time, and probably is not a result of varying sedimentation rates. Two sampled sections in the Arumbera Sandstone separated by 80 km both contain the long normal interval followed by the interval of mixed polarity, the detailed comparison of which demonstrates that the Arumbera-Box Hole boundary is unconformable. Elements from the late Precambrian Mt Skinner fauna in the Arumbera Sandstone indicate that the long normal interval is entirely pre-Cambrian, and that the base of the Cambrian occurs within the interval of mixed polarity.

A comparison with an additional site sampled across a fossil occurrence in the Central Mount Stuart Formation at Central Mount Stuart indicates that at least 1 of the Upper Proterozoic fossils, Hallidaya brueri, has a considerable vertical distribution in time.

If used properly, the magnetic polarity pattern discussed herein offers the possibility of precise intercontinental correlations of stratigraphic sequences near the base of the Cambrian. It is suggested that a stratotype sequence for the base of the Cambrian be chosen in such a manner that the boundary position corresponds to a geomagnetic reversal.

Type
Articles
Information
Geological Magazine , Volume 115 , Issue 2 , March 1978 , pp. 139 - 150
Copyright
Copyright © Cambridge University Press 1978

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References

Cloud, P. 1973. Possible stratotype sequences for the basal Palaeozoic in North America. Am. J. Sci. 273, 193–206.CrossRefGoogle Scholar
Cowie, J. W. & Glaessner, M. F. 1975. The Precambrian–Cambrian boundary: A Symposium. Earth-Sci. Rev. 11, 209–51.CrossRefGoogle Scholar
Daily, B. 1974. The Precambrian–Cambrian boundary in Australia. Specialist group in biostratigraphy and paleontology: Precision in Correlation, Programmes and Abstracts, Hobart.Google Scholar
Glaessner, M. F. & Walter, M. R. 1975. New Precambrian fossils from the Arumbera Sandstone, Northern Territory, Australia. Alcheringa 1(1).CrossRefGoogle Scholar
Irving, E. & Pullaiah, G. 1976. Reversals of the geomagnetic field, magnetostratigraphy, and relative magnitude of palaeosecular variation in the Phanerozoic. Earth-Sci. Rev. 12, 35–64.CrossRefGoogle Scholar
Kirschvink, J. L. 1977. The Precambrian–Cambrian Boundary Problem: Primary and secondary palaeomagnetic directions from the Amadeus Basin, Central Australia. (In preparation.)Google Scholar
McElhinny, M. W. & Embleton, B. J. J. 1976. Precambrian and Early Palaeozoic Palaeomagnetism in Australia. Phil. Trans. R. Soc. Lond. A 280, 417–31.CrossRefGoogle Scholar
McElhinny, M. W., Luck, G. R. & Edwards, D. 1971. A large volume magnetic field-free space for thermal demagnetization and other experiments in palaeomagnetism. Pure Appl Geoph. 90, 126–30.CrossRefGoogle Scholar
Nairn, A. E. M. & Peterson, D. N. 1973. A review of Permian and Triassic palaeomagnetic data with respect to palaeogeographic conditions at, and the location of, the Permian–Triassic boundary. In The Permian and Triassic Systems and Their Mutual Boundary (ed. Logan, A. and Hills, L. V.), pp. 694–713. Can. Soc. Pet. Geol. Memoir 2.Google Scholar
Smith, K. G. 1972. Stratigraphy of the Georgina Basin. Bull. Bur. Min. Res. 111, 1972.Google Scholar
Steiner, M. R. & Helsley, C. E. 1975. Reversal pattern and apparent polar wander for the Late Jurassic. Bull. geol. Soc. Am. 86, 537–1543.2.0.CO;2>CrossRefGoogle Scholar
Wells, A. T., Forman, D. J., Ranford, L. C. & Cook, P. J. 1970. Geology of the Amadeus Basin, Central Australia. Bull. Bur. Min. Res. 100.Google Scholar