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USGS · 70013595

The Mohnian-Luisian boundary in the Coccolithus miopelagicus subzone, with new and related species of forminifers.

R.E. Arnal
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Abstract

New information obtained from samples colleced in a 1979 cruise is presented for the Luisian-Mohnian (Miocene) boundary. In some areas of the S California Borderland, the early Mohnian-Luisian boundary apparently occurs within the Coccolithus miopelagicus subzone. To suppor this statement, the location of the samples and a list of the diagnostic foraminifers are provided for each sample in part I of this report. Fifteen species and one variety of new or undescribed benthic foraminifers which were observed in the course of this and other studies of the foraminiferal content of Dart core samples from the S California Borderland are reported and described in part II. The genus Bolivina is represented by 3 new species and 1 species previously undescribed. There are also 2 new species each of Uvigerina, Siphogenerina, Cassidulina, and Ehrenbergina; one undescribed species and a new variety of Megastomella; and one new species each of Epistominella and Concavella. -from Author

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R.E. Arnal. 1984. The Mohnian-Luisian boundary in the Coccolithus miopelagicus subzone, with new and related species of forminifers.. https://doi.org/10.2113/gsjfr.14.1.1

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