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Refinement of late-Early and Middle Miocene diatom biostratigraphy for the east coast of the United States

Geosphere

By:
, , , and
DOI: 10.1130/GES00864.1

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Abstract

Integrated Ocean Drilling Program (IODP) Expedition 313 continuously cored Lower to Middle Miocene sequences at three continental shelf sites off New Jersey, USA. The most seaward of these, Site M29, contains a well-preserved Early and Middle Miocene succession of planktonic diatoms that have been independently correlated with the geomagnetic polarity time scale derived in studies from the equatorial and North Pacific. Shallow water diatoms (species of Delphineis, Rhaphoneis, and Sceptroneis) dominate in onshore sequences in Maryland and Virginia, forming the basis for the East Coast Diatom Zones (ECDZ). Integrated study of both planktonic and shallow water diatoms in Hole M29A as well as in onshore sequences in Maryland (the Baltimore Gas and Electric Company well) and Delaware (the Ocean Drilling Program Bethany Beach corehole) allows the refinement of ECDZ zones into a high-resolution biochronology that can be successfully applied in both onshore and offshore regions of the East Coast of the United States. Strontium isotope stratigraphy supports the diatom biochronology, although for much of the Middle Miocene it suggests ages that are on average 0.4 m.y. older. The ECDZ zonal definitions are updated to include evolutionary events of Delphineis species, and regional occurrences of important planktonic diatom marker taxa are included. Updated taxonomy, reference to published figures, and photographic images are provided that will aid in the application of this diatom biostratigraphy.

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Additional Publication Details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Refinement of late-Early and Middle Miocene diatom biostratigraphy for the east coast of the United States
Series title:
Geosphere
DOI:
10.1130/GES00864.1
Volume
9
Issue:
5
Year Published:
2013
Language:
English
Publisher:
Geological Society of America
Contributing office(s):
Earthquake Science Center
Description:
16 p.
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
Larger Work Title:
Geosphere
First page:
1286
Last page:
1302
Country:
United States
Other Geospatial:
East Coast