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Circular structures of large scale and great age on the Earth's surface

A Corrigendum to this article was published on 01 February 1978

Abstract

THE Earth's surface exhibits faint circular patterns which have not been described before. These circles are characterised by near perfection of outline, by the presence of topographic highs (rims) along parts of their circumferences, by their generally large scale (diameters of from under 7 km up to approximately 700 km in the areas examined), and by their definition in various geological environments, in many rock types, and in rocks of all ages. Many of the circles are intermittent in places along their rims but about 55% of the approximately 1,170 definite circles observed to date can be visually traced around an entire 360° of arc. The circles are further characterised by the presence of fracturing and brecciation along parts of their rims and by the extraordinary control they place on regional geology in general and on ore mineralisation in particular.

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References

  1. Gay, S. P., Jr Pervasive Orthogonal Fracturing in Earth's Continental Crust, 105–106 (American Stereo Map Co., Salt Lake City, 1973).

    Google Scholar 

  2. Lindsay, J. B. Geomorphology of Arizona, 1 : 1,000,000 (Salt Lake City).

  3. Mardirosian, C. A. Map of Mining Districts and Mineral Deposits of Arizona, 1 : 1,000,000 (Mineral Research Co., Albuquerque, 1973).

    Google Scholar 

  4. Wilson, E. D., Moore, R. T. & Cooper, J. R. Geologic Map of Arizona 1 : 500,000 (Arizona Bureau of Mines and US Geological Survey, 1969).

    Google Scholar 

  5. Titley, S. R. & Hicks, C. L. (eds) Geology of the Porphyry Copper Deposits—Southwestern North America, 7 (University of Arizona Press, Tucson, 1966).

  6. Kutina, J. Proc. 1st Int. Conf. Basement Tectonics, 567 (Utah Geological Association, Salt Lake City, 1976).

    Google Scholar 

  7. Emmons, W. H. Trans. Am. Inst. Min. Met. Eng. 75, 797–815 (1927).

    Google Scholar 

  8. Grew, P. C. Trans. Am. geophys. Union 57, 4 (abs.) (1976).

    Google Scholar 

  9. Godwin, C. I. Proc. Geol. Ass. Can. 25, 9–12 (1973).

    Google Scholar 

  10. Jerome, S. E. & Cook, D. R. Bull. Nev. Bur. Mines 69, (1967).

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SAUL, J. Circular structures of large scale and great age on the Earth's surface. Nature 271, 345–349 (1978). https://doi.org/10.1038/271345a0

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