Plate Reorganisation Events Governed by Episodic Mismatch Between Mantle Convection and Plate Network
Abstract
Based on the current plate motion, we analyse the distribution of spreading and subduction. Subduction tends to be grouped around two poles while spreading tends to form a girdle, with attests for the evolutionary tendency of the plate network. This degree two pattern is the opposite of the deep mantle convection pattern, which shows on the contrary two upwelling columns separated by a downwelling wall. The present plate network shows a compromise between the two opposite patterns. Based on the tectonic history since 550 Ma, we claim that episodic plate reorganisations, because they counteract the evolutionary trend of the plate network, maintain the compromise.
- Publication:
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AGU Spring Meeting Abstracts
- Pub Date:
- May 2004
- Bibcode:
- 2004AGUSM.T33A..04R
- Keywords:
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- 8120 Dynamics of lithosphere and mantle: general;
- 8150 Plate boundary: general (3040);
- 8155 Plate motions: general