@Mouse: I'm glad you also like the land shapes! I was at first very daunted about figuring out the tectonics, but I love puzzles and can be a perfectionist, so it is quite enjoyable so far.
@Pixie. Many thanks for your detailed comments - the board is very lucky to have someone willing to share such expertise!
I have reworked the map based on your comments. The main points/questions (as noted in pink numbers on the map) are:
1) The Sapun landmass was originally attached to Sitan and has rifted, colliding into Shilan, leading to ocean spreading down the middle. I imagine this to be quite an old split.
2) Similarly, Aos was originally part of Chilean but has split, and has now collided with Sitan. I am trying to decide whether the Sitan-Aos or the Sapun-Shilan collision should be the newest? Do the tectonics give any clue? This will help me decide mountain heights.
3) As you pointed out not much ocean-spreading was happening, the Ayabba plate has split. This is a very ancient ocean, I imagine.
4) The Hutuppu Ocean originally also encompassed the Qutrus ocean, but this has split as part of it is dragged towards Qutrus.
5) There are some minor plates. I wanted a South-American style mountain range, so I created a minor plate which is moving in slightly different direction from Ayabba, colliding more directly with the Shilan Coast. I'm not sure how plausible this is? Minor plate 6 was created so I could include a small island chain somewhere around there.
I am most bothered by the boundary between the Aos Plate and the Hutuppu Ocean Plate: Aos is moving South-East, away from Shilan but Hutuppu is moving North-West so there isn't really a clear ocean-spreading in that area where convergent and divergent boundaries meet.
I am still slightly unsure about the polar ocean plates, but I would like them to not interfere too much with the current set up.
Thanks again!
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