Global magnetic field characteristics during the Matuyama-Brunhes reversal: insights from global field models
| Autor: | Mahgoub, A., Korte, M., Panovska, S. |
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| Rok vydání: | 2023 |
| Zdroj: | XXVIII General Assembly of the International Union of Geodesy and Geophysics (IUGG) |
| DOI: | 10.57757/iugg23-3387 |
| Popis: | Magnetic field reversals, which occur when the polarity of the field reverses and the global field strength drops to its lowest level, are the most significant changes in the Earth's magnetic field identified by paleomagnetic data collected mostly from volcanic and sediment records. Matuyama-Brunhes (MB), the most recent field reversal that happened ~780,000 ago, is documented by tens of these records, offering the opportunity to study the mechanism of reversal and features of the magnetic field during polarity transition globally. Nevertheless, some MB records lack precise chronology information, have challenges with magnetization acquisition (sediments), provide discontinuous paleomagnetic data (volcanics), and they are unevenly distributed around the globe. Such limitations raise doubt on some proposed magnetic field features during MB, such as preferred virtual geomagnetic poles (VGP) paths, recurring VGP clusters, and precursor and rebound phases. Likewise, using these non-ideal data records for constructing spherical harmonic global models may result in an inaccurate interpretation of the transition field, including field morphology and the evolution of dipole and non-dipole field contributions. We constructed a suite of global models based on various data sets. Data inputs are classified according to type, geographic distribution, age data reliability, temporal resolution, reliability of demagnetization and relative paleointensity results, and consistency of these results among adjacent records. By comparing the model outputs from each data category, we will identify the robust magnetic field characteristics during MB reversal. The 28th IUGG General Assembly (IUGG2023) (Berlin 2023) |
| Databáze: | OpenAIRE |
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