Dynamic time warping of palaeomagnetic secular variation data

• Published in: Geophysical Journal International
• Main Authors: Hagen, Cedric J, Reilly, Brendan T, Stoner, Joseph S, Creveling, Jessica R
• Other Authors: National Science Foundation, American Research Center in Sofia, Oregon State University
• Format: Article in Journal/Newspaper
• Language: English
• Published: Oxford University Press (OUP) 2020
• Subjects: Geochemistry and Petrology; Geophysics; North Atlantic
• Online Access: http://dx.doi.org/10.1093/gji/ggaa004; http://academic.oup.com/gji/advance-article-pdf/doi/10.1093/gji/ggaa004/31776806/ggaa004.pdf; http://academic.oup.com/gji/article-pdf/221/1/706/36181520/ggaa004.pdf

SUMMARY We present and make publicly available a dynamic programming algorithm to simultaneously align the inclination and declination vector directions of sedimentary palaeomagnetic secular variation data. This algorithm generates a library of possible alignments through the systematic variation of assumptions about the relative accumulation rate and shared temporal overlap of two or more time-series. The palaeomagnetist can then evaluate this library of reproducible and objective alignments using available geological constraints, statistical methods and expert knowledge. We apply the algorithm to align previously (visually) correlated medium to high accumulation rate northern North Atlantic Holocene deposits (101–102 cm ka–1) with strong radiocarbon control. The algorithm generates plausible alignments that largely conform with radiocarbon and magnetic acquisition process uncertainty. These alignments illustrate the strengths and limitations of this numerical approach.