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Title: Data report: depths of Site U1553 off-splice data adjusted to the Site U1553 splice, IODP Expedition 378
A near-complete sedimentary sequence was spliced together for the upper part of International Ocean Discovery Program (IODP) Holes U1553A, U1553B, and U1553E. Poor core recovery precluded a complete splice for the deeper section cored in Holes U1553C and U1553D. The history of Deep Sea Drilling Project Site 277, which was cored nearby, suggests that the Site U1553 splice will be heavily sampled and that eventually samples will be taken from intervals of core that are not included in the splice (i.e., off-splice). Although the depths of all cores have been shifted to a common scale during the splicing process by aligning significant features shared by cores from the different holes, core disturbance and natural variability often lead to misalignment between features in the splice and the same features in off-splice data. To remedy this problem for future sampling, data from off-splice intervals are squeezed or stretched to match spliced intervals using a set of tie points between the splice and off-splice data. The difference in depths can be significant when considering sedimentation rates and orbital periods of precession, obliquity, and eccentricity and sometimes even change the phase relationship compared to the splice. Results are presented as tables of tie points between each hole and the splice that can be used to interpolate the proper splice depth of off-splice samples.  more » « less
Award ID(s):
1326927
PAR ID:
10349022
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Proceedings of the International Ocean Discovery Program
Volume:
378
Issue:
202
ISSN:
2377-3189
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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