High Geomagnetic Intensity During the Mid-Cretaceous from Thellier Analyses of Single Plagioclase Crystals
-
- John A. Tarduno
- Department of Earth and Environmental Sciences, University of Rochester, Rochester, NY, 14627, USA.
-
- Rory D. Cottrell
- Department of Earth and Environmental Sciences, University of Rochester, Rochester, NY, 14627, USA.
-
- Alexei V. Smirnov
- Department of Earth and Environmental Sciences, University of Rochester, Rochester, NY, 14627, USA.
書誌事項
- 公開日
- 2001-03-02
- DOI
-
- 10.1126/science.1057519
- 公開者
- American Association for the Advancement of Science (AAAS)
この論文をさがす
説明
<jats:p> Recent numerical simulations have yielded the most efficient geodynamo, having the largest dipole intensity when reversal frequency is low. Reliable paleointensity data are limited but heretofore have suggested that reversal frequency and paleointensity are decoupled. We report data from 56 Thellier-Thellier experiments on plagioclase crystals separated from basalts of the Rajmahal Traps (113 to 116 million years old) of India that formed during the Cretaceous Normal Polarity Superchron. These data suggest a time-averaged paleomagnetic dipole moment of 12.5 ± 1.4 × 10 <jats:sup>22</jats:sup> amperes per square meter, three times greater than mean Cenozoic and Early Cretaceous–Late Jurassic dipole moments when geomagnetic reversals were frequent. This result supports a correlation between intervals of low reversal frequency and high geomagnetic field strength. </jats:p>
収録刊行物
-
- Science
-
Science 291 (5509), 1779-1783, 2001-03-02
American Association for the Advancement of Science (AAAS)
