Artifexian on YouTube released a video, Where Metals Are Found on Fantasy Worlds!, that goes into depth on where and why different deposits should appear. It's incredibly interesting and prompted me to do the same for the Shielded Sea region of the Kirinioth map.
I didn't follow his guide exactly (and it's likely that oil won't ever come up in the game world), but it gave me a decent idea of where to place certain materials, and helps shape how each of the nations would evolve. I made sure to place plenty of valuable deposits near the dwarf nation.
I should probably add something here.