many examples are fairly obvious, like Detroit Techno and Trap named after Detroit, several named after Chicago, the various "X Sound" genres (Bakersfield, Birmingham, Donosti, Dunedin, Jersey, Manila, Minneapolis, and Nashville), but also others like Merseybeat (named after the river that flows through Liverpool), Delta Blues (named after the Mississippi River delta), or Dirty South and Dixieland (two nicknames for the southern United States)

(I don't think I'm proposing we create areas for rivers and vague areas tho, lol)