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Thread: I need some help with my first map

  1. #1

    Default I need some help with my first map

    Hi everybody,

    I'm Ysgramor and this is my first map. I want to know if my continents have a good (believable) shape and if they are in a good position.

    Sorry if I'm making english mistakes, I'm french

    Thank you for your help!

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  2. #2
    Software Dev/Rep Hai-Etlik's Avatar
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    I assume from the 2:1 aspect ratio that this is meant to be in Plate Carree projection. That should produce significant distortion of the polar regions which your map doesn't show. The two small continents in the north should be stretched out east to west. Since they aren't, it means the "real" shape on the globe is pinched in toward the poles.

    Here's what it looks like in a polar stereographic projection which shows the pinching.
    Click image for larger version. 

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    Plate Carree is simple and convenient for data that is going to be reprojected, but it's not a very good choice for a finished map.

    Your coastlines are also a bit consistent. If you look at Earth, you'll see that the degree of "crinkleyness" varies. There are smooth areas like the Atlantic coasts of Africa and South America, and there are massively complex areas, like Southeast Asia or Scandinavia.

    You do have a bit of a divergent boundary thing going with the two larger continents that resembles the Atlantic basin. That's good. The west coast of the big one looks like it fits with the east coast of the smaller one. I'd suggest you play that up by not running any tall, young mountains along those coastlines. Old rounded ones like the Appalachians (Which run along the east coast of the United states) would fit though.

    You're also rather lacking in islands. There are a exceptions, but in general, most major islands are found along convergent boundaries, along with young mountains. Such islands essentially are just mountains or mountain ranges that are partly underwater (Japan, the Philippines, Indonesia, Vancouver Island), while the other kind like are essentially partly flooded plateaus (Great Britain, Greenland, the Canadian Arctic), or mountains in odd places (Hawaii, Iceland).

  3. #3

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    Thank you for the help Hai-Etlik

    The projection is Plate Carree but the continents are not disorted, so I probably need a new projection where I could work without the distortion, if you have any idea

    Is there a way to know where the coastline should be more complex or more smooth?

    Also, I have some island chains in mind but I dont really know how to draw them so I will add them later.

    Also, do you know where basin forms?

    Tanks again for the help

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    Software Dev/Rep Hai-Etlik's Avatar
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    Quote Originally Posted by Ysgramor View Post
    Thank you for the help Hai-Etlik

    The projection is Plate Carree but the continents are not disorted, so I probably need a new projection where I could work without the distortion, if you have any idea
    No projection can eliminate distortion. All you can do is move the distortion around, and change what gets distorted. All projections distort linear scale. Some manage to preserve angles (Such projections are called "Conformal") and some preserve areas (And are called "Equal Area" or "Equivalent") but never both. Equidistant Cylindrical (Which Plate Carree is a special case of) distorts both area and angles, what it preserves is linear scale, but only in one direction, North-South in Plate Carree. This is why there are lots, and lots of different projections in order to preserve what's important for any particular map as well as possible. Most projections also have some sort of centre point or line (sometimes two lines) where they minimize distortion. Distortion then increases the further you get from that point or line. In Plate Carree it's the equator, in the Stereographic projection I used, it's the north pole.

    Plate Carree does have the advantage that you can easily run it through a program like G.Projector to get it into a wide range of projections easily. Software that can start in other projections tends to a be a lot more complicated, so you might want to try just drawing the distortion into the map and then projecting it. The distortion takes the form of stretching things out from east to west, with the amount of stretching increasing as you get closer to the poles.

    Quote Originally Posted by Ysgramor View Post
    Is there a way to know where the coastline should be more complex or more smooth?
    Generally, the more complex coastlines are a result of convergent tectonic boundaries, where plates are, or have smashed together. Where they are moving apart, things tend to be simpler. Southeast Asia has multiple convergent boundaries. Continental seas, where part of a continent is flooded can also have more complex boundaries, the North Sea, Baltic Sea, Hudson Bay, and the Northwest Passage are examples of continental seas.

    Quote Originally Posted by Ysgramor View Post
    Also, do you know where basin forms?
    Ocean Basins form where continents move apart.

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    On Earth, The Atlantic is a comparatively "recent" example of an ocean basin forming when North and South America split apart from Africa and Eurasia. The Great Rift Valley, Red Sea, and Gulf of Aden are examples of the same process at much earlier stages.

  5. #5

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    Thanks again for the help Hai, you're a really good guy

    One more thing, can you tell where a lake forms? Is it only where multiple rivers join or it is about the topography of the land?

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    Quote Originally Posted by Ysgramor View Post
    Thanks again for the help Hai, you're a really good guy

    One more thing, can you tell where a lake forms? Is it only where multiple rivers join or it is about the topography of the land?
    A lake occurs when there's a basin to hold it. If there's a nice downhill gradient, water will flow down it taking the best path, and you have a river. Sometimes it flows down into a basin with no downhill route out from it, and it builds up. Eventually it reaches a point where it can flow out and you get a river. This means you have to consider the shape of the terrain. Mountain lakes tend to be spidery, spindly shapes filling the valleys between the mountains while lakes on plains are more compact.

    There are a few lakes that are "Endorheic". The Dead Sea, Aral Sea, Caspian Sea, and Great Salt Lake are all examples. These have no river outlet. Water flows in, and then evaporates. They only occur in quite dry conditions, usually well inland. There are also a few rivers that just spread out over a flood plain and evaporate without flowing into a lake or ocean.

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