| Autor: |
Brenner AR; Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA 02138., Fu RR; Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA 02138., Kylander-Clark ARC; Department of Earth Science, University of California, Santa Barbara, CA 93106., Hudak GJ; Natural Resources Research Institute, University of Minnesota, Duluth, MN 55812., Foley BJ; Department of Geosciences, The Pennsylvania State University, State College, PA 16802. |
| Jazyk: |
angličtina |
| Zdroj: |
Proceedings of the National Academy of Sciences of the United States of America [Proc Natl Acad Sci U S A] 2022 Nov; Vol. 119 (44), pp. e2210258119. Date of Electronic Publication: 2022 Oct 24. |
| DOI: |
10.1073/pnas.2210258119 |
| Abstrakt: |
The paleomagnetic record is an archive of Earth's geophysical history, informing reconstructions of ancient plate motions and probing the core via the geodynamo. We report a robust 3.25-billion-year-old (Ga) paleomagnetic pole from the East Pilbara Craton, Western Australia. Together with previous results from the East Pilbara between 3.34 and 3.18 Ga, this pole enables the oldest reconstruction of time-resolved lithospheric motions, documenting 160 My of both latitudinal drift and rotation at rates of at least 0.55°/My. Motions of this style, rate, and duration are difficult to reconcile with true polar wander or stagnant-lid geodynamics, arguing strongly for mobile-lid geodynamics by 3.25 Ga. Additionally, this pole includes the oldest documented geomagnetic reversal, reflecting a stably dipolar, core-generated Archean dynamo. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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