Worldbuilding (part 3: Topology 101) (31/3/2012)
Orright orright, we can get to the map now, and from here on in I’m going to assume that that everything is mostly earth-like (barring any features whose origins have already been covered). That is, the world is round, orbits a sun, spins on its axis and has evolved over a very long period of time to become what it is. Just a few notes on the alternatives:
a) If the world is flat then you clearly have a fundamentally difference cosmology and nothing you do from there on in will make any less sense, so I reckon you might as well go to town. Just give it some sort of underlying logic for how the universe works and apply that logic rigorously and you’ll do fine. I had a world that was a 10000km diameter mushroom once. It had an underside that consisted of canyons and ridges all hundreds of miles deep and a 10000km stalk. And really, that was about as far as it went and it worked just fine for what it was intended. Not sure I’d write a novel there though.
Also, a flat earth will struggle to have a magnetic field. Stuff like that.
b) Orbits a sun – see above. If a world does orbit a sun and doesn’t spin on its axis then it ought to be tide-locked to its sun and most of the world will be uninhabitably cold or hot; and if it somehow manages to have an atmosphere that doesn’t simply freeze solid and fall out of the sky on the cold side, the temperature variations are likely to cause constant storms of apocalyptic proportions. To be honest, I haven’t ever looked at this possibility in detail before and it sounds kinda fun, but that’s not where most fantasy worlds go, so that’s not where I’m going with these posts.
c) Didn’t evolve? That how was it made? Created out of nothing by the gods? Fine. Then do what you like. Give your god or gods a little personality and make a world that they would have made. But then we’ve covered this already.
Right. Mountains and seas. Very basically, mountains basically get made by tectonic plates crashing into each other and getting all surly about things (Andes, Sierras, Himalayas) or by volcanic action through soft spots in the earth’s crust (Mid-Atlantic Ridge). These often occur together. Go to wikipedia and read a bit about Plate Tectonics and Formation of Mountains and really you’re about done. Very basic basics? Mountains come in ranges. They can be long linear ones or patches. Old mountains tend to be less steep and thus more habitable and passable, having been eroded over time, while young mountains tend to be sharper and more jagged. Volcanoes can appear in mountain ranges or on their own. They also tend to last a good long time, so old mountains might have been volcanoes once but are now extinct. About the only way you can really go wrong with mountains is to pock-mark them over the world like crates on the moon, to the point where they look like they’re some sort of cosmological acne.
Seas? They fill in the low bits. If you want them to. A world with a much greater proportion of its surface covered in sea is largely going to follow recognisable earth-like behaviour for climate. A much lower proportion and it probably isn’t and the difference is probably going to be less moisture in the air and less rainfall and much larger areas of lifeless desert land. But that’s just an educated guess.
It’s very unlikely that anyone (except maybe me) is going to pick at your map and start pointing out the underlying flaws in your geology. Do what you like, but do the mountains RANGES and the coastlines first because what comes next is the climate and what comes after that are the rivers and the wildlife and that starts to tell you where the people will be, and all that starts with the mountains. If you want the odd solitary mountain added later, that’s not going to upset anything om a wide scale, unless what you add is a solitary mountain that happens to be a hundreds of miles long and twenty miles high.
Done with mountains now. Climate next.