A note, left behind by Antiquarian Abbingdon in Syleio Seko
Dispatched by Magistrate Ragsdale to these ruins, he believes it was called "Syleio Seko". No way to know if it is true, but I've updated my maps with the name.
Given what the Magistrate has told me of the Siren Queen's activities in these areas, it makes sense to investigate them further. I've seen many points where her crew has hauled Ancient relics away, even chipping down walls and columns to get at their goals. Since all of the smaller or easily accessible relics have already been hauled away, I'm going to continue searching some of the harder to reach locations.