Mathematics – Logic
Scientific paper
Feb 1985
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1985jgr....90.1963t&link_type=abstract
Journal of Geophysical Research, Volume 90, Issue B2, p. 1963-1982
Mathematics
Logic
34
Scientific paper
A recently developed zonal model for the last geomagnetic field reversal, which describes time- and latitude-dependent transitional behavior of intensity and inclination in terms of dominance of low-order field harmonics, was tested using a latitudinal and chronological succession of transition records. The primary data were derived from a high-resolution study of five Matuyama to Brunhes deep-sea cores collected along a 40° meridional band in the north-central Pacific. The transitions analyzed were the onsets and terminations of the Olduvai and Jaramaillo events and the Matuyama-Brunhes boundary. Supplementary data, published by previous workers, included a Jaramillo onset record from the southern Indian Ocean and a transition recorded in the Triassic Chugwater Formation of North America. In a general sense, the measured inclination and intensity records indicate the Jaramillo transitions and the last reversal to be remarkably similar to each other and to differ from the Olduvais. Crosscorrelation of the measured data sets with synthetic zonal harmonic records for the core latitudes indicates that the zonal harmonic model does predict the behavior of Matuyama-Brunhes reversal in the northern hemisphere. For the older reversals, however, the present model requires substantial modification. This is particularly so in the case of the Jaramillo onset: although two inclination and intensity records of this transition from northern and southern hemisphere sediments strongly resemble each other, the current model produces a synthetic record for one hemisphere that is incompatible with that hemisphere's measured data. Further, to model zonally the Olduvai reversals (for which a wide latitudinal northern hemisphere sampling was available), a substantially different ratio of low-order multipole components from that of the standard model is required, and the modeled solution was unsatisfactory at very low latitude. A modified zonal harmonic approach, which introduces a small sectoral component, may offer a solution to the incompatibilities uncovered by the present study.
Hammond Stephen R.
Herrero-Bervera Emilio
Hsu Vindell
Theyer Fritz
No associations
LandOfFree
The zonal harmonic model of polarity transitions: A test using successive reversals does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The zonal harmonic model of polarity transitions: A test using successive reversals, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The zonal harmonic model of polarity transitions: A test using successive reversals will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1592754