[Terr_]

Resembles an unhelpfully simple

https://www.amcharts.com/voronoi-treemap/

[roryokane]

Yeah, I was about to post that it looked like some hybrid of a voronoi diagram and a treemap. More about those diagram types that can be combined in this manner:

https://en.wikipedia.org/wiki/Voronoi_diagram

https://en.wikipedia.org/wiki/Treemapping