Nature 386, 262 - 266 (20 March 1997); doi:10.1038/386262a0

Low-latitude glaciation in the Palaeoproterozoic era

D. A. Evans^*, N. J. Beukes^† & J. L. Kirschvink^*

^*Division of Geological and Planetary Sciences 170-25, California Institute of Technology, Pasadena, California 91125, USA
^†Department of Geology, Rand Afrikaans University, Auckland Park 2006, Johannesburg, South Africa

One of the most fundamental enigmas of the Earth's palaeoclimate concerns the temporal and spatial distributions of Precambrian glaciations. Through four billion years of Precambrian history, unequivocally glacial deposits have been found only in the Palaeoproterozoic and Neoproterozoic record¹. Nonetheless, some of these deposits are closely associated with tropical— rather than just polar—palaeolatitudinal indicators such as carbonate rocks, red beds, and evaporites^1,2. These observations are quantitatively supported by palaeomagnetic results indicating a 5° latitude for Neoproterozoic glaciogenic rocks in Australia^3–5. Similarly reliable palaeolatitudes for the older, Palaeoproterozoic glaciogenic rocks have not yet been obtained, as such deposits commonly suffer from poor preservation and secondary magnetic overprinting. The Archaean–Palaeoproterozoic 'Transvaal Supergroup' on the Kaapvaal craton in South Africa is, however, exceptionally well preserved, and is thus amenable to the palaeomagnetic determination of depositional palaeolatitudes. Within this supergroup the 2.2 billion-year old Ongeluk lavas are a regionally extensive, largely undeformed and unmetamorphosed, extrusive volcanic succession⁶, which conformably overlies glaciogenic deposits (the Makganyene diamictite). Here we report a palaeomagnetic estimate of 11 5° depositional latitude for the lavas, and hence for the underlying contemporaneous glacial rocks. The palaeoclimate enigma is thus deepened; a largely ice-free Precambrian world was apparently punctuated by two long ice ages, both yielding glacial deposits well within tropical latitudes.

1. Hambrey, M. J. & Harland, W. B. Earth's Pre-Pleistocene Glacial Record (Cambridge Univ. Press, Cambridge, 1981).
2. Chumakov, N. M. & Elston, D. P. Episodes 12, 115−119 (1989).
3. Embleton, B. J. J. & Williams, G. E. Earth Planet. Sci. Lett. 79, 419−430 (1986). | Article | ISI |
4. Schmidt, P. W., Williams, G. E. & Embleton, B. J. J. Earth Planet. Sci. Lett. 105, 355−367 (1991). | Article |
5. Sohl, L. E. & Christie-Blick, N. Geol. Soc. Am. Abst. Program. 27, A204 (1995).
6. Tankard, A. J. et al. Crustal Evolution of Southern Africa: 3.8 Billion Years of Earth History (Springer, New York, 1982).
7. Beukes, N. J. in Mineral Deposits of Southern Africa (eds Anhaeusser, C. R. & Maske, S.) 819−828 (Geol. Soc. S. Africa, Johannesburg, 1986).
8. Eriksson, P. G. & Reczko, B. F. F. J. Afr. Earth Sci. 21, 487−504 (1995). | Article |
9. Button, A. thesis, Univ. Witwatersrand (1973).
10. Cornell, D. H., Schütte, S. S. & Eglington, B. L. Precambr. Res. 79, 101−123 (1996). | Article | ChemPort |
11. Burger, A. J. & Coertze, F. J. Ann. Geol. Surv. S. Afr. 10, 135−141 (1975).
12. Steiger, R. H. & Jäger, E. Earth Planet. Sci. Lett. 36, 359−362 (1977). | Article | ISI | ChemPort |
13. Trendall, A. F. et al. in 3rd Int. Archean Symp. (eds Glover, J. F. & Ho, S. E.) 81−83 (Geoconferences (W.A.), Perth, 1990).
14. Walraven, F., Armstrong, R. A. & Kruger, F. J. Tectonophysics 171, 23−48 (1990). | Article |
15. Briden, J. C. Phil. Trans. R. Soc. Land. A 280, 405−416 (1976).
16. Hattìngh, P. J. & Pauls, N. D. Precambr. Res. 69, 229−240 (1994).
17. Symons, D. T. A. Geology 3, 303−306 (1975). | Article |
18. Roy, J. L. & Lapointe, P. L. Can. J. Earth Sci. 13, 749−773 (1976). | ISI |
19. Morris, W. A. Geology 5, 137−140 (1977). | Article |
20. Buchan, K. L., Mortensen, J. K. & Card, K. D. Precamb. Res. 69, 1−10 (1994).
21. Miyano, T. & Beukes, N. J. Trans. Geol Soc. S. Afr. 87, 111−124 (1984).
22. Stratigraphy of South Africa (South African Committee for Stratigraphy, Pretoria, 1980).
23. Beukes, N. J. & Smit, C. A. S. Afr. J. Geol. 90, 378−394 (1987).
24. Eyles, N. Earth Sci. Rev. 35, 1−248 (1994).
25. De Villiers, P. R. & Visser, J. N. J. Trans. Geol. Soc. S. Afr. 80, 1−8 (1977).
26. Visser, J. N. J. thesis, Univ. Orange Free State (1969).
27. Neumiller, C. M. thesis, Northern Illinois Univ. (1990).
28. Visser, J. N. J. Trans. Geol Soc. S. Afr. 74, 187−199 (1971).
29. Kirschvink, J. L. Geophys. J. R. Astron. Soc. 62, 699−718 (1980). | ISI |
30. Grobler, N. J. & Botha, B. J. V. Trans. Geol Soc. S. Afr. 79, 53−57 (1976).
31. Fisher, N. L., Lewis, T. & Embleton, B. J. J. Statistical Analysis of Spherical Data (Cambridge Univ. Press, 1987).
32. Van der Voo, R. Tectonophysics 184, 1−9 (1990). | Article |
33. Williams, G. E. Earth Sci. Rev. 34, 1−45 (1993). | Article | ISI |
34. Kirschvink, J. L. in The Proterozoic Biosphere: A Multidisciplinary Study (eds Schopf, J. W. & Klein, C.) 51−52 (Cambridge Univ. Press, 1992).