2014.1.27 submitted to GJI

2014.1.28 awaiting reviewer scores

2014.3.1 awaiting editor recommendation & awaiting decision

2014.3.3 Major revision

2014.6.7 revised manuscript submitted

Two reviewers gave a total comments of 3 pages.

Major issues of reviewer 1:

1. Why not put yield stress parameter in this study? ( We have already set up a model space which investigating  6 parameters in this study)

2. Convince him this mobile lid convection can give a degree-2 structure, and compare this to a previous paper.

Major issues of reviewer 2:

1. Use a more balanced way to address the current debate of this issue.

2. Compare and explain the thermal structures to some seismic studies.