Planktonic foraminiferal assemblage of the Yorktown Formation, Virginia, USA

H.J. Dowsett; L.B. Wiggs

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USGS · 70017143

Planktonic foraminiferal assemblage of the Yorktown Formation, Virginia, USA

H.J. Dowsett·L.B. Wiggs

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Abstract

Planktonic foraminifers from Coastal Plain deposits in southeastern Virginia provide biochronologic control and paleoceanographic information for the lectostratotype of the Yorktown Formation and type localities of its four members. Faunas recovered from six localities are consistent with faunas reported from the Yorktown in North Carolina and Yorktown correlatives (Duplin and Raysor Formations) from Georgia to North Carolina and support an age assignment between 3.0 and 4.0 Ma. Quantitative estimates of surface temperature based upon the planktonic foraminifer assemblages indicate winter conditions 3?? to 5??C warmer than today and summer conditions essentially equivalent to today during Yorktown deposition. -Authors

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H.J. Dowsett, L.B. Wiggs. 1992. Planktonic foraminiferal assemblage of the Yorktown Formation, Virginia, USA. https://pubs.usgs.gov/publication/70017143

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