Catastrophic initiation of subduction following forced convergence across fracture zones
Abstract
Although the formation of subduction zones plays a central role in plate evolution, the processes and geological settings that lead to the initiation of subduction are poorly understood. Using a visco-elastoplastic model, we show that a fracture zone could be converted into a self-sustaining subduction zone after approximately 100 km of convergence. Modeled initiation is accompanied by rapid extension of the over-riding plate and explains the inferred catastrophic boninitic volcanism associated with Eocene initiation of the Izu-Bonin-Mariana (IBM) subduction zone. Using global plate reconstructions, we suggest that IBM nucleation was associated with a change in plate motion between 55 and 45 Ma. We estimate that the forces resisting IBM subduction initiation were substantially smaller than available driving forces.
Additional Information
© 2003 Elsevier Science B.V. Received 20 December 2002; received in revised form 22 April 2003; accepted 29 April 2003. We thank Y. Podladchikov and A. Poliakov for sharing their PARAZOV program. Reviews by D. Blackman, R. Stern, and S. Zhong greatly clarified the manuscript. This work was supported by NSF Grants EAR-0003558 and EAR-0107137, and is Contribution No. 8944 of the Seismological Laboratory.Attached Files
Supplemental Material - mmc1.avi
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Additional details
- Eprint ID
- 35579
- DOI
- 10.1016/S0012-821X(03)00242-5
- Resolver ID
- CaltechAUTHORS:20121120-142052670
- NSF
- EAR-0003558
- NSF
- EAR-0107137
- Created
-
2012-11-21Created from EPrint's datestamp field
- Updated
-
2021-11-09Created from EPrint's last_modified field
- Caltech groups
- Seismological Laboratory
- Other Numbering System Name
- Caltech Seismological Laboratory
- Other Numbering System Identifier
- 8944