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Title: Data report: paleomagnetic directions from IODP Expedition 354, Hole U1451A, Cores 23H and 24H
International Ocean Discovery Program (IODP) Expedition 354 Site U1451 was drilled as the easternmost of seven sites forming a transect across the Bengal Fan at 8°N. Site U1451 recovered the oldest Bengal Fan sediments of the expedition, providing a long sedimentary record and valuable chronostratigraphic constraints on seismic imaging. Two cores recovered from Hole U1451A, Cores 23H and 24H, had uninterpretable archive-half remanent magnetizations measured on ship, despite having a calcareous clay lithology that was generally suitable for magnetostratigraphy in middle Pleistocene sediments. Shipboard biostratigraphy places these cores around the Pliocene/Pleistocene boundary. Paleomagnetic measurements of discrete subsamples, reported here, indicate that both Cores 23H and 24H contain no magnetic reversals, implying each core was deposited during a single polarity chron. These results suggest, based on sedimentation rate estimates, that the Gauss–Matuyama reversal and the Pliocene/Pleistocene boundary in Hole U1451A is located between the base of Core 23H and top of Core 24H (129.54–131.33 m CSF-A), although this needs to be confirmed by postexpedition biostratigraphic studies.  more » « less
Award ID(s):
1326927
PAR ID:
10229643
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Proceedings of the International Ocean Discovery Program
Volume:
354
ISSN:
2377-3189
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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