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Title: Chronostratigraphy and spatial distribution of magnetic sediments in the Chukchi and Beaufort seas since the last deglaciation

Palaeomagnetic investigation of three sediment cores from the Chukchi and Beaufort Sea margins was performed to better constrain the regional chronostratigraphy and to gain insights into sediment magnetic properties at the North American Arctic margin during the Holocene and the preceding deglaciation. Palaeomagnetic analyses reveal that the sediments under study are characterized by low‐coercivity ferrimagnetic minerals (magnetite), mostly in the pseudo‐single domain grain‐size range, and by a strong, stable, well‐defined remanent magnetization (MAD<5°). Age models for these sediment cores were constrained by comparing their palaeomagnetic secular variations (inclination, declination and relative palaeointensity) with previously published and independently dated sedimentary marine records from the study area. The magnetostratigraphical age models were verified byAMSradiocarbon dating tie points, tephrochronology and210Pb‐based sedimentation rate estimate. The analysed cores 01JPC, 03PCand 02PCspanc. 6000, 10 500 and 13 500 cal. aBP, respectively. The estimated sedimentation rates were stable and relatively high since the deglaciation in cores 01JPC(60 cm ka−1) and 03PC(40–70 cm ka−1). Core 02PCshows much lower Holocene sedimentation rates with a strong decrease after the deglaciation from ~60 to 10–20 cm ka−1. Overall, this study illustrates the usefulness of palaeomagnetism to improve the dating of late Quaternary sedimentary records in the Arctic Ocean.

 
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NSF-PAR ID:
10048061
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
Boreas
Volume:
47
Issue:
2
ISSN:
0300-9483
Page Range / eLocation ID:
p. 544-564
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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