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Discrediting the late Eocene microspherule layer at Cynthia, Mississippi

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Abstract

Glassy microspherules recently reported from the late Eocene of central Mississippi are physically and chemically similar to impact-produced microspherules, especially those from Molino de Cobo, Spain, leading several investigators to conclude that these samples document another late Eocene impact event. A careful evaluation of the sample site and spherule compositions, however, suggests that these glasses are modern contaminants. Similar contaminants could be widespread throughout industrialized countries.

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... Some workers have suggested that they can resolve six layers in the composite stratigraphic section, using a graphic correlation technique of microfossil assemblages [23,24] (Fig. 2A). Others argue that the ¢rst and last occurrences of these fossils can be diachronous, and so the correlation of layers separated by only a few thousand years exceeds the limits of resolution of this technique [25]. ...
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A new late Eocene microspherule layer in central Mississippi
  • Byerly G. R.
Age of the upper Yazoo Formation in central Mississippi
  • Dockery D. T.