Compilation of palaeomagnetic data from sediments and volcanic rocks from 68 sites spanning 30,000 to 50,000 years ago used to create the temporally continuous global spherical harmonic geomagnetic field model LSMOD.1. This is in supplement to the paper "Earth's magnetic field is (probably not reversing" (Brown et al. 2018)
A description of how the data were treated is given in SI Appendix of the associated publication. A full list of complementary data sources (references) is given is provided with the data.
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For the volcanics there is one file
volc.txt
The headers are:
Age[ka] - age in thousands of years before present (0 = 1950 AD).
Error[ka] - uncertainty on the age.
Lat[Deg] - Latitude of site in degrees.
Lon[Deg] - Longitude of site in degrees.
Dec[Deg] - Declination in degrees.
Inc[Deg] - Inclination in degrees.
Alpha95[Deg] - 95% circular confidence limit on the directional data.
F[microT] - intensity in micro Tesla.
F_Error[microT] - uncertainy on the intensity in micro Tesla.
-9999 - no data
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For the sediments there are two types of files, those that end *.txt and those that end *int.txt.
*.txt - directional data with the headers:
Age[ka] - age in thousands of years before present (0 = 1950 AD).
Lat[Deg] - Latitude of site in degrees.
Lon[Deg] - Longitude of site in degrees.
Dec[Deg] - Declination in degrees.
Inc[Deg] - Inclination in degrees.
-9999 - no data
*int.txt - scaled intensity data using PADM2M (as described in Section S1.3 of SI Appendix)
Age[ka] - age in thousands of years before present (0 = 1950 AD).
Lat[Deg] - Latitude of site in degrees.
Lon[Deg] - Longitude of site in degrees.
F[microT] - Scaled intensity in micro Tesla.
6 of the sediment data sets are individual records (BLS, CHI, MIN, PYR, SIO, S01).
6 of the sediment data sets are stacks of records (BBS, NAS, NPS, OBS, SBS, SAS).
All details of the records are given in Table S1 and Table S2 of the SI Appendix of the associated publication.
This dataset contains the paleomagnetic supplementary material to the article Kelder et al. (subm.), which presents a magnetostratigraphic correlation of Late Miocene lacustrine sediments based on multi-polarity greigite. The multi-polarity is visible in most thermal paleomagnetic results (Zijderveld diagrams) by antipodal high and medium temperature components, while only one magnetic component was visible in the alternating field demagnetization diagrams. Based on this complex behavior, a tailored demagnetization approach was developed to allow for reliable magnetostratigraphic dating of lacustrine sediments.
The dataset includes demagnetization data from four drill cores located nearby Paks, Hungary. They were not oriented, meaning that only the inclination could be used for paleomagnetism. The measurements took place at the Paleomagnetic Laboratory Fort Hoofddijk in Utrecht University, The Netherlands. For details about the methodology the reader is referred to the methodology in Kelder et al. (subm).
Three types of data are distinguished:
• Thermal demagnetization results (.th files)
• Alternating field demagnetization results (.af files).
• Interpreted magnetic vectors for demagnetization files (.dir files)
The .th, .af. and .dir files can be viewed with Notepad or similar programs, and analyzed via the Open Source platform Paleomagnetism.org (Koymans et al., 2016). The .dir files only exist for the cores PAET-30 and PAET-34, because these were interpreted in detail, while the material of the other cores (PAET-26, 27) were mainly used for rock magnetic purposes.
Finally, an overview of the data files, abbreviations and sample codes is provided in the data description file.