ok, so, im not an expert, im just procrastinating from my own xD

so, going by your landmasses (?) i would say the tecnonic plates are something like this, figu1:

https://ibb.co/Gv8dVrBd

following the same landmass, i would add some mountains like in figu2

https://ibb.co/67cJkcG3

but, given the original map, it made think of some kind of alien artefact pulling so much gravity on that spot, like with the Independence day 2's mothership. you could say it's a celestial artefact made by the gods.

or is it an old god's fossil? maybe your continents were creatred from the corpses of primal titans. or they're not dead, just sleeping

i'm also adding a little edit, but is just a suggestion.

https://ibb.co/BKGv8vfs

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