A new visualization of the motion of the Indian Plate in the Cenozoic
Abstract
90 million years ago the Indian Plate detached from the ancient supercontinent Gondwana and diverged away from the Antarctic and African plates in a northwest-wards direction. Evidence from magnetic anomalies and paleomagnetic data shows that between 67 and 49 million years ago spreading rates increased the Indian plate to anomalously rapid velocities, with a peak of nearly 200 mm/yr relative to the African plate. Cande and Stegman (2011) have shown new evidence that the Indian Plate acceleration was caused by a push force originating from the Reunion mantle plume. Two notable slowdowns occurred during that time period: a sharp reduction in velocity at 63 million years ago, and another more gradual reduction from 52 to 45 million years ago. The first slowdown coincides with rapidly dwindling flood basalt eruptions caused by the plume head of the Reunion mantle plume. The second slowdown is thought to be due to collision with either the Eurasian continent or a now extinct intermediate plate that may have contained an island arc. We are motivated to create a new visual model using new data and considering the Reunion plume as a driving force. Using the GPlates tectonics modeling software and rotation data developed by the EarthBytes Project we reconstruct the trajectory to develop a velocity vector model of the Indian plate. We use these tools to explore alternative plate reconstructions, such as one that includes a collision between India and a hypothetical intraoceanic arc beginning at 52 Ma (Ali and Aitchison, 2008) to help explain the reduction in plate velocity over the 7 million year span during the second slowdown.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2011
- Bibcode:
- 2011AGUFM.T23D2437H
- Keywords:
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- 8120 TECTONOPHYSICS / Dynamics of lithosphere and mantle: general;
- 8137 TECTONOPHYSICS / Hotspots;
- large igneous provinces;
- and flood basalt volcanism;
- 8157 TECTONOPHYSICS / Plate motions: past