I've tried searching and haven't found anything regarding this, so I'll make this suggestion.
In the current game, if you embark anywhere with a sedimentary layer, you are pretty much guaranteed to get iron ore, coal, probably platinum etc; the same goes for other layer types, there are always some metals to be found.
I suggest that it would be more realistic if certain useful or valuable materials such as gold, iron etc could only be found in certain places in the world, and once those locations were known they would be the cause of wars as various civilizations attempted to gain control of them.
Information could perhaps be available in the embark screen, for regions known to contain certain resources, but if you chose to embark on such a location you would know your fort may end up in the front line of a war, particularly if the area was claimed by another civilization. If on the other hand you embarked on an area not known to contain resources you could expect a much more peaceful setting, but one that is unlikely to contain anything of high value (unless you discovered a previously unknown deposit of an ore or gem etc, in which case you might have a 'gold rush'-like influx of migrants, but also attract the attention of enemies)
Obviously it would be related to worldgen, as the older the world is, the more likely it would be that all the useful resources have already been discovered (and perhaps exhausted).
Essentially what I am suggesting is that the approximate locations of major resources is determined on a worldwide level during worldgen rather than being placed at embark in any stone types that could contain that resource (which I assume is the case at the moment, as things like Reveal can reveal all the available rock types.)
I feel this would better both geologically and as a more realistic reason for wars than the current ethics system; I'm no great expert but I think more wars have been fought over territory and resources than because some other civilization thinks it's OK to eat each other while ours doesn't. (even if 'ethical' reasons have sometimes been used as an excuse.)
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Topic: Wars over limited resources (Read 620 times)