Research ArticleGEOPHYSICS

Synchronizing volcanic, sedimentary, and ice core records of Earth’s last magnetic polarity reversal

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Science Advances  07 Aug 2019:
Vol. 5, no. 8, eaaw4621
DOI: 10.1126/sciadv.aaw4621
  • Fig. 1 Lava flow sequences that record transitional geomagnetic field behavior associated with the Matuyama-Brunhes reversal.

    Vertical axes are the lava flow site numbers from the original studies arranged in order of eruption from oldest at the bottom to youngest on top. VGP lat., virtual geomagnetic pole latitude in degrees. 40Ar/39Ar ages (in thousand years) for dated flows are shown with ±2σ analytical uncertainties. The paleomagnetic directional data are from Punaruu South, Tahiti (29); Quebrada Turbia West-10 and West-11, Chile (30); Los Tilos, La Palma (31); Punaruu North, Tahiti (see the Supplementary Materials) (16); Guadeloupe (17); and Haleakala (14). The red open circles are determinations of the virtual dipole moment (VDM) for samples measured in this study from Haleakala (see the Supplementary Materials), Punaruu North [data from (16)], and Chile [data from (27)].

  • Fig. 2 Age spectra and isochrons from four representative M-B lava samples in Table 1.

    Samples from bottom to top are from Punaruu North, Chile, La Palma, and Haleakala, respectively.

  • Fig. 3 Correlation of volcanic, sedimentary, and ice core records of geomagnetic field behavior associated with the Matuyama-Brunhes reversal.

    (A) VGPs from dated lavas in each of the seven sections of Fig. 1 are shown with 2σ age uncertainties. The VGPs of undated flows that crop out between dated flows are plotted using the weighted mean age calculated for transitional lavas in each section and are shown without age uncertainty. The purple, blue, and pink vertical bands are the weighted mean ages of lavas in Punaruu North, Chile, and Guadeloupe combined, and Punaruu South, La Palma, and Haleakala combined, respectively, as discussed in the text. (B) High–deposition rate marine sediment records of VGP evolution, each placed on its independent astronomical age model (data sources in Table 2) that is not tied to an M-B reversal age. (C) Paleointensity proxy records spanning the M-B reversal. Plotted are relative paleointensity (RPI) records (×20) for ODP 984, ODP 1308, and MD90-961 sediment cores; the virtual axial dipole moment (VADM; units of 1022 Am2) for the PISO 1500 stack of 13 marine records; and 10Be flux records [104 atoms/g/cm2 for the Epica Dome (EDC) Antarctic ice core; authigenic decay-corrected 10Be × 108 atoms/g for the MD98-2183 marine sediment core; data sources in Table 2)]. Lava VDMs are from this study (table S2) and (16, 27). Note that for gauging paleointensity only, the unfilled stars for normally and reversely magnetized lavas are shown at the same age as the weighted mean age of the associated transitional lavas; see Fig. 1 for ages of these flows.

  • Fig. 4 VGPs from seven lava flow sequences (located at the “×” symbols) that record the M-B reversal process.

    The historic NAD antipodes (i.e., the average position and antipode of the maximum vertical field of the Australian NAD flux patch between 1590 and 1995 AD) are from (28).

  • Table 1 Summary of 40Ar/39Ar data from lava flow sites.

    Ages calculated relative to 1.1864 Ma Alder Creek sanidine standard (37). Decay constants are from (52). Atmospheric 40Ar/36Ar = 298.56 ± 0.31 (57). No. of expts, number of experiments performed on each sample. N, number of steps included from the total.

    SampleVGP lat.
    (°)
    No. of
    expts
    Total fusion40Ar/36Ari ± 2σIsochronN39Ar %MSWDPlateau
    Age
    (ka) ± 2σ
    Age
    (ka) ± 2σ
    Age
    (ka) ± 2 σ
    Haleakala
    H-15-2980.61618 ± 19300 ± 6617 ± 6610 of 1195.50.87627.0 ± 16.0
    H-15-2884.22734 ± 5300 ± 4715 ± 2323 of 3475.30.98725.6 ± 5.2
    86C529A/27B286.51732 ± 8300 ± 7717 ± 6614 of 1688.70.44727.9 ± 9.2
    85M001A/27B86.52744 ± 3302 ± 5740 ± 1417 of 2176.50.89749.2 ± 3.5
    H-15-27A−44.23764 ± 5299 ± 3767 ± 1940 of 5188.10.50771.0 ± 4.5
    H-15-27−47.94752 ± 4298 ± 3781 ± 2246 of 6976.10.67770.8 ± 4.2
    84C436A/25A−38.24766 ± 3298 ± 3778 ± 2559 of 7779.40.86773.9 ± 3.5
    H-15-24A−16.71754 ± 3299 ± 6776 ± 139 of 1582.80.29775.7 ± 4.3
    H-15-2462.03756 ± 7297 ± 3772 ± 2533 of 5877.20.92773.4 ± 6.3
    H-15-21−67.56753 ± 4298 ± 3775 ± 2059 of 8085.00.41771.7 ± 3.6
    Quebrada Turbia, Chile
    QTW11-2087.41711 ± 8295 ± 9754 ± 319 of 1477.80.93740.4 ± 7.2
    QTW11-1980.21742 ± 19297 ± 6775 ± 966 of 984.10.91758.0 ± 21.0
    QTW11-16−24.81766 ± 5299 ± 7780 ± 1910 of 1678.40.63781.7 ± 5.8
    QTW11-11−26.11754 ± 6299 ± 7770 ± 2811 of 1778.90.43781.4 ± 5.6
    QTW11-5−25.71775 ± 4299 ± 10787 ± 2410 of 1683.61.60786.3 ± 5.3
    QTW11-3−21.81766 ± 7296 ± 6783 ± 2811 of 1878.40.79785.0 ± 6.6
    QTW10-10−25.61779 ± 4296 ± 6787 ± 1310 of 1291.50.77782.0 ± 5.1
    QTW10-5−18.61779 ± 2297 ± 9776 ± 178 of 2156.71.13784.2 ± 3.1
    QTW10-3−8.91782 ± 3296 ± 8787 ± 712 of 1495.80.85785.3 ± 3.8
    Guadeloupe
    GA0207B−61.01713 ± 16298 ± 6784 ± 638 of 1467.80.29786.0 ± 15.0
    GA010B−14.41746 ± 8298 ± 14778 ± 428 of 1380.10.64786.3 ± 7.5
    GD0103B−79.01766 ± 7299 ± 4772 ± 169 of 1564.90.83783.5 ± 6.8
    Tahiti: Punaruu South
    TT−34.01743 ± 6296 ± 10778 ± 418 of 1763.20.60777.4 ± 6.1
    R1V−33.12768 ± 8300 ± 4766 ± 1515 of 3071.60.73774.4 ± 5.4
    R1T−41.91741 ± 6294 ± 8791 ± 469 of 1857.50.56777.0 ± 6.9
    R1S−73.51755 ± 8301 ± 7772 ± 249 of 1677.70.75789.1 ± 6.2
    Tahiti: Punaruu North
    TM2874.61713 ± 9299 ± 8761 ± 408 of 1363.00.41772.6 ± 9.3
    TM3081.51734 ± 10300 ± 4765 ± 2611 of 1784.10.69774.4 ± 8.7
    TM3162.52771 ± 5297 ± 3785 ± 1317 of 2978.10.65791.1 ± 4.6
    TM32−71.92745 ± 9298 ± 5789 ± 3419 of 3780.40.81795.5 ± 6.7
    TM24−24.52769 ± 4296 ± 4795 ± 1318 of 2979.31.07792.4 ± 3.8
    TM2346.61775 ± 9298 ± 3788 ± 1510 of 1581.60.56794.3 ± 7.1
    TM2743.51792 ± 7294 ± 19796 ± 267 of 1267.90.49801.1 ± 6.7
    TM20-561.32772 ± 6298 ± 3785 ± 1521 of 3584.30.65793.6 ± 4.6
    TM1856.51752 ± 8297 ± 12790 ± 446 of 1462.10.47794.4 ± 6.7
    TM13−70.01689 ± 10298 ± 8821 ± 466 of 1356.10.34819.0 ± 13.0
    La Palma
    TN1576.71681 ± 13299 ± 3675 ± 3620 of 2294.10.47687.0 ± 11.0
    TN16−5.42765 ± 5298 ± 1766 ± 1243 of 4693.40.85771.7 ± 4.3
    TN17−31.11762 ± 9299 ± 3762 ± 2915 of 1992.30.76774.3 ± 7.9
    TN20−31.62739 ± 6296 ± 6785 ± 2916 of 3470.70.97774.8 ± 5.3
  • Table 2 Summary of high-resolution sedimentary and ice core records of the M-B reversal.

    SiteSite locationLatitudeLongitudeMaterialAccumulation
    rate
    Age modelReferences
    ODP site 984N. Atlantic
    Ocean, Bjorn
    Drift
    60.4−23.6Sediment core9 cm/kaOrbitally tuned
    O-isotope
    (34, 59)
    ODP site 1308N. Atlantic
    Ocean/DSDP site
    609
    49.9−24.2Sediment core16–18 cm/kaOrbitally tuned
    O-isotope
    (34, 60)
    ODP site 1306N. Atlantic
    Ocean, Eirik Drift
    58.2−45.6Sediment core15 cm/kaOrbitally tuned
    O-isotope/
    tandem with RPI
    (2, 61)
    MD site 90-961Indian Ocean5.173.8Sediment core5 cm/kaOrbitally tuned
    O-isotope
    (9)
    Osaka BayOsaka Bay, Japan34.7135.2Sediment core60 cm/kaOrbitally tuned
    diatom record of
    sea level change
    (10, 11, 62)
    ChibaBoso peninsula,
    Japan
    35.3140.14Outcrop63 cm/kaO-isotope
    benthic forams
    correlated to
    ODP 1123
    (12, 13, 20)
    PISO 1500Composite
    paleointensity
    stack
    13 sediment
    cores
    O-isotope–
    coupled
    correlation to RPI
    records
    (63)
    MD site 97-2143Philippine Sea,
    10Be
    paleointensity
    proxy
    15.87124.7Sediment core1.4 cm/kaOrbitally tuned
    O-isotope
    (42)
    Epica Dome CAntarctica, 10Be
    paleointensity
    proxy
    −75.1123.3Ice coreO-isotopes in ice,
    with tie points
    orbitally tuned
    (13, 20, 44, 45)

Supplementary Materials

  • Supplementary material for this article is available at http://advances.sciencemag.org/cgi/content/full/5/8/eaaw4621/DC1

    Fig. S1. Age spectra and isochron diagrams of legacy and new 40Ar/39Ar experiments.

    Fig. S2. Stratigraphic relationship of 34 lava flows of the lava sequence in the northern wall of Punaruu Valley, Tahiti, that are based on the field observations of Mochizuki et al. (16).

    Fig. S3. AF demagnetization results for flow A27 in Balbas et al. [(36), supplementary file, p. 29].

    Fig. S4. AF demagnetization results for flow site A27 (sample TM23-5-1) in Mochizuki et al. (16).

    Fig. S5. AF demagnetization results for flow site B1 (sample TM32-9-1) in Mochizuki et al. (16).

    Fig. S6. AF demagnetization results for flow site B1 in Balbas et al. [(36), supplementary documents. p. 32].

    Fig. S7. Comparison of WiscAr ages and the plateau ages determined by Balbas et al. (36) using a multicollector mass spectrometer with Faraday detectors (uncertainties are ±2σ analytical).

    Fig. S8. Cumulative probability distribution of 40Ar/39Ar dates.

    Fig. S9. An example of Tsunakawa-Shaw paleointensity result (sample 85M033-11 from Haleakala flow unit number 53, which is field site 26 in Fig. 1) that meets criteria A.

    Fig. S10. An example of Tsunakawa-Shaw paleointensity result (sample H-15-27A-12 from Haleakala flow unit number 59, which is lava site no. 27A in Fig. 1) that meets criteria B.

    Fig. S11. Paleointensity estimates from lava flows of the lava sequence in Haleakala caldera on Maui.

    Fig. S12. Representative thermomagnetic curves.

    Table S1. Typical system blanks for legacy dates and Noblesse multicollector dates.

    Table S2. Results of Tsunakawa-Shaw paleointensity experiments on samples from the lava sequence of Haleakala caldera on Maui.

    Table S3. Summary of absolute paleointensity estimates from the lava sequence of Haleakala caldera, Maui.

    Table S4. Summary of relative paleointensity estimates from the lava sequence of Haleakala caldera, Maui.

    Data S1. Table of complete 40Ar/39Ar results.

    Data S2. Age spectrum and isochron plots of 40Ar/39Ar results.

  • Supplementary Materials

    The PDF file includes:

    • Fig. S1. Age spectra and isochron diagrams of legacy and new 40Ar/39Ar experiments.
    • Fig. S2. Stratigraphic relationship of 34 lava flows of the lava sequence in the northern wall of Punaruu Valley, Tahiti, that are based on the field observations of Mochizuki et al. (16).
    • Fig. S3. AF demagnetization results for flow A27 in Balbas et al. (36), supplementary file, p. 29.
    • Fig. S4. AF demagnetization results for flow site A27 (sample TM23-5-1) in Mochizuki et al. (16).
    • Fig. S5. AF demagnetization results for flow site B1 (sample TM32-9-1) in Mochizuki et al. (16).
    • Fig. S6. AF demagnetization results for flow site B1 in Balbas et al. (36), supplementary documents. p. 32.
    • Fig. S7. Comparison of WiscAr ages and the plateau ages determined by Balbas et al. (36) using a multicollector mass spectrometer with Faraday detectors (uncertainties are ±2σ analytical).
    • Fig. S8. Cumulative probability distribution of 40Ar/39Ar dates.
    • Fig. S9. An example of Tsunakawa-Shaw paleointensity result (sample 85M033-11 from Haleakala flow unit number 53, which is field site 26 in Fig. 1) that meets criteria A.
    • Fig. S10. An example of Tsunakawa-Shaw paleointensity result (sample H-15-27A-12 from Haleakala flow unit number 59, which is lava site no. 27A in Fig. 1) that meets criteria B.
    • Fig. S11. Paleointensity estimates from lava flows of the lava sequence in Haleakala caldera on Maui.
    • Fig. S12. Representative thermomagnetic curves.
    • Table S1. Typical system blanks for legacy dates and Noblesse multicollector dates.
    • Table S2. Results of Tsunakawa-Shaw paleointensity experiments on samples from the lava sequence of Haleakala caldera on Maui.
    • Table S3. Summary of absolute paleointensity estimates from the lava sequence of Haleakala caldera, Maui.
    • Table S4. Summary of relative paleointensity estimates from the lava sequence of Haleakala caldera, Maui.

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    Other Supplementary Material for this manuscript includes the following:

    • Data S1 (Microsoft Excel format). Table of complete 40Ar/39Ar results.
    • Data S2 (.pdf format). Age spectrum and isochron plots of 40Ar/39Ar results.

    Files in this Data Supplement:

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