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Title: Pliocene to modern Southern Ocean diatom biostratigraphy revised using samples from IODP Expedition 382
Abstract. Biostratigraphy is frequently used to generate age models and is significant to understanding the rate and timing of Cenozoic climate change. Records from the Southern Ocean (SO) are particularly valuable in understanding the past behavior of the Antarctic Ice Sheet, whereby clues to this behavior can be gained from the presence and composition of preserved microfossils. Diatoms, a nearly ubiquitous group of microalgae that make cell walls out of opal, preserve well in Southern Ocean sediments and have been used extensively in Southern Ocean biostratigraphy. Here, we present an updated diatom biostratigraphy of the Southern Ocean extending 3.3 Myr from sediments recovered during International Ocean Discovery Program (IODP) Expedition 382 “Iceberg Alley” Site U1537. Furthermore, we compare a tuned age model to a paleomagnetic-based age model to provide two independent estimates of ages of these datums with quantified uncertainty. The high sedimentation rate found at Site U1537 allows detailed age assessment, allowing the generation of more finely tuned age models in Southern Ocean sediments.  more » « less
Award ID(s):
2302832 2114777 2114786
PAR ID:
10651236
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Journal of Micropalaeontology
Date Published:
Journal Name:
Journal of Micropalaeontology
Volume:
44
Issue:
2
ISSN:
2041-4978
Page Range / eLocation ID:
497 to 507
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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