Abstract
Slab dip varies significantly, both between different, and along single subduction zones. Provided that old subducting plates are colder and denser than young plates, variations in the slab dip should correlate with slab age. However, recent statistical analyses do not show this expected correlation. We present the results of non‐Newtonian numerical dynamic models where subduction is driven by means of a kinematic boundary condition. We systematically vary the age of both the overriding and subducting plates in order to test these effects on the slab dip at different depth ranges. We find that colder overriding plates result in shallower slab dips and episodes of flat slab subduction, as a result of the increased suction force in the mantle wedge. The influence of the thermal state of the overriding plate on slab dip is shown here to be more important than that of the age of subducting lithosphere. Modeling results are qualitatively compared to the large dip variability of the Cocos slab including a flat‐slab segment. We suggest that this variability is likely related to the change of the thermal state of the overriding plates, with flat subduction occurring under cold lithosphere in southwestern Mexico and steep subduction under the warmer lithosphere of the northwestern Caribbean plate.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.