WIP: unnamed Earh-like planet

[NedS298]

Your mountains are unusual, but not unpleasant. You seem to have put them in odd places though.

[groovey]

I noticed Tear's tutorial is probably best fit for continental or regional maps, but there's a lovely map that I stumbled upon a few years back in the guild's gallery when I was just a casual lurker, by Schwarzkreuz, Photo 17 of 19 from Showcase. I've always had this map in mind and I'd like for mine to have a similar feel. The author of the map said he used Tear's tutorial, though it's obvious he made the most of it and added his own touch to make it look so polished and professional.

So IF I managed to represent my mountain ranges in a similar manner to his, would they make more sense in the world map scale?

NedS298, what do you mean? Would you mind sharing your thoughts? To be honest, there are only two places on which the current tectonics dictate mountains placement, and the two of them are on the eastern continent/s (because they are actually two plates mashed together), as indicated by blue circles:



The rest of them I'm mostly free to place as I see, with a certain logic of course, as they would be cheaply explained by being the result of previous tectonics, and thus would be older eroded mountain ranges. I'm not sure where to place them though, but I know I need some in certain areas to get important enough rivers.

Having that in mind, I'd like to hear your input.

Pixie, I'm very surprised I got what you meant right in my first try, thanks a lot again for that suggestion, that area of the map plays a somehow significant role in the story and the history of the eastern part of the map, so it's great to know it a bit better. Now I'll be focusing on terrain, but I might get back to the tectonics at some point to polish them and make them less robotic, but without interfering, too much, with the dynamic of plates 1, 2 (this one I wouldn't mind edit in shape as long as it collided with number 2 to created a mountain range), 3, 11 (to be coherent with 3) and the new one created after your suggestion, because those are the ones I need to work like they do now. The rest of them I wouldn't mind messing around more with, I could even edit the terrain as needed later on, if needed, so the revised tectonics and the terrain would match. I know this is a terrible system to make a map, but I can't get myself to do it in order, like I should. Meh, I should try to get it right, I'll try to give it more thought I guess, after all, I'm still experimenting with mountains to see if I get the hang of it so the final result is not random.

[groovey]

Sigh. So, I polished the plates a bit more and kind of started fresh with the directions.

First I added the general direction of each plate, and then just started to work on the specific boundaries, but I'd like to know if I'm doing it right before doing more, because it takes some time to place each damn subduction triangle in the right angle to the boundary. I also know how I'll represent transformation boundaries, with yellow arrows, but I still don't know how to represent divergent boundaries, color would be red, but with what? Arrows in opposite directions like I did in the previous tectonic map?



Two things I need to ask:

1. The direction where the subduction triangles are pointing indicate which plate subducts into which plate right? In my case, for example, plate 8 subducts into plate 9, and nº3 to nº1 (at least north of the boundary), is that right?

2. I forgot while I wrote nº1.

From checking out different tectonic maps of Earth, I think I got the general idea of how it works, in those maps, but in mine I find it difficult to know which segments of the boundary is what when said boundary meets with more than one plate, and to know how the general direction of the plate affects each boundary meeting.

For example, what I did in boundary of nº8 and 9, would subduction happen across ALL the boundary, or in some segments it wouldn't be subduction?

Is the boundary between plate nº7 and 3 indeed a transformation one? All through it?

Sooo, I'd appreciate some advice, I've read about tectonics a bit, here and there, to understand the basics (because as I said, if I try to go hardcore on it my head hurts), but when it's time to apply it to my map... I'm not sure of what I'm doing.

And yes, I'm aware that the new polished tectonics makes the world even more similar to Earth... that's what happens when you have limited artistic vision to improvise, really, I'm almost a robot, so Mother Earth's copyright free suggestions work for me.

Also, I'd like to take a moment to thank you all for checking my WIP and giving me support, advice and opinions to keep improving it, especially since the thread is a bit of a mess: it started with terrain and tectonics, then a total re-do, tectonics, terrain, and now tectonics again... Let's hope it's all worth it and I end up with a decent finished map for the novel and world-building.

[jbgibson]

Keep talking - I for one am finding it all interesting!

[NedS298]

On a plate boundary you should have land, continents don't form perpendicularly to their corresponding plate boundary/ies (very often), look at a world tectonic plates map. South America is a good examples of this. It's because uplift will occur on the plate going over the other, which will in turn make a valley. Two plates bordering on continental crust will create even larger mountain ranges with plateaus behind them (ie. lots of land). Two ocean plates colliding will give you islands like Indonesia and the Philippines, New Zealand, and the Caribbean islands. So on both your collision and transform plate boundaries, you should have land or islands - not a whole heap of sea. Currently, all your islands are on oceanic rifts (mid-ocean ridges) which does happen but not near as often island chains on (or behind, because of hot magma from the subducting plate rising through the crust again) collision or transform boundaries.
Too late to make changes now though, don't worry about it.

[Pixie]

Groovey, your questions made me rethink some of my own conceptions about tectonics and plate movement and go back to the drawing board on my own "fiction planet". Thanks for that!
From start, I chose the ignore most the times that plates movement is always rotational around a fictional pole (called Euler pole). I thought for larger plates, the rotation would be very small and thus we could think about it linear terms. However, on second thought, that's not the case and it's very much the opposite. Large plates is actually where it makes a bigger difference. So, I looked around a little bit and found this interesting resources:

explaining euler pole
euler pole movement applied to the boundary between north american plate and pacific plate

I also thought of a way to picture this with PS (or Gimp):
- create a layer on top of the the map and place a solid color shape exactly fitting the plate you want to look at
- on another layer draw a little cross to mark the euler pole of that plate
- under <edit>, select the option rotate - a small cross with a circle appears in the middle of the selection
- move that circle to the position where you placed the cross and then rotate the shape
- this allows to experiment with the plate movement and to figure out where subduction, transform and crust formation is happening

(this is an extra effort to get things right and may or may not end up to be useful, I haven't quite experimented enough with it yet - I also suspect it won't work well on plates too close to the poles)

Now, as for your specific questions:

1. The direction where the subduction triangles are pointing indicate which plate subducts into which plate right? In my case, for example, plate 8 subducts into plate 9, and nº3 to nº1 (at least north of the boundary), is that right?

Yes, your blue triangles are in the correct positions.
Modern geology thinks collisions between continents are not exactly subduction, though, they just bend, fold and pile up, neither of the plates actually sinks.

For example, what I did in boundary of nº8 and 9, would subduction happen across ALL the boundary, or in some segments it wouldn't be subduction?

Is the boundary between plate nº7 and 3 indeed a transformation one? All through it?

Try that "rotation" trick I described above.. it will show you the right answer, I think.

Also, you have the tendency to place island chains in oceanic rifts. While there's a few islands and island chains along Earth's rifts, they don't generate the New Zealand size islands you have.

I think this version is a common (I got it now, it messed up what I had and now it's awful, it will come out much better on the next try). Keep ploughing away!

[groovey]

The last two posts made me think a lot, my head hurts (don't get me wrong, I'm not scared of thinking, on the contrary, I love it, but I'm more fit for social science, I'm an Historian after all. Natural science on the other hand is much more complex for me to grasp). They made me realize I do need to place islands on some oceanic boundaries and that to know where exactly I need to know the rotation axis on the plates (the Euler pole Pixie introduced me to, and the technique he came up to represent it on PS or GIMP is both simple and effective, it does help me indeed), which will also help me solve my problem of not knowing the boundaries movements.

However, I'm going to need a lot of processing to figure it out and fix the map.

Quick question:

- Islands originated in divergent boundaries TEND to be smaller than those created on convergent boundaries, true or false?

- So when two continental collide, if subduction doesn't occur, how do you represent it on a map? With what symbol?

Pixie, you mean this WIP of yours? http://www.cartographersguild.com/re...ke-planet.html. I've checked it out a few times. I love what you did with the heightmap on that lovely pinguin, and observed your tectonics as a reference, so if you are going to re-do or edit the tectonics of the map, please, will you be so kind to post the updated tectonics?

[Pixie]

However, I'm going to need a lot of processing to figure it out and fix the map.

Well, yes, I figured. My map will also need a lot of re-processing. Furthermore, since I found out that rotation gives very different results depending on the projection.. And then I searched the web reading stuff about it and it seems (as sure as I can be now) that the projection to get this right needs to be stereographic.
So, my task will be, in the near future, to create stereographic projections of my original map. Several of them (stereographic projection, which G.projector can produce, cannot show a whole sphere at once), one for each plate, centered on it. And then work out their movement.

- Islands originated in divergent boundaries TEND to be smaller than those created on convergent boundaries, true or false?

- So when two continental collide, if subduction doesn't occur, how do you represent it on a map? With what symbol?

The only islands on divergent boundaries is when they coincide with a hotspot - Iceland and Azores are the only examples I can think of (as they are closest to me - I reckon most of the times it's actually no islands formed!
Even though there is no actual subduction (plate sinking and melting), I think it is represented in the same way (this is a detail we can very much not worry about)

Pixie, you mean this WIP of yours? http://www.cartographersguild.com/re...ke-planet.html.

Yes, that's the world I am working on for some time. And yes, once I find the time to reconfigure tectonics I will post updates... Again, groovey, thanks for making be rethink my knowledge on tectonics and improve my own map .

[groovey]

As if it hadn't gotten complex enough for me, he he, now there's also the projection to keep in mind! I'll try to grasp my head around that. Does it mean the way you devised to check the rotation on PS or GIMP won't give accurate results,I mean, as simplified as it is? Because to be honest, unless the results would be VERY different from those you would get by keeping in mind stereographic projection, I think it would be enough for me.

And you don't need to thank me, It's only fair you got something back of all this, after all your suggestions and help and patience to help me understand this whole thing better.

[ascanius]

Groovey, your questions made me rethink some of my own conceptions about tectonics and plate movement and go back to the drawing board on my own "fiction planet". Thanks for that!
From start, I chose the ignore most the times that plates movement is always rotational around a fictional pole (called Euler pole). I thought for larger plates, the rotation would be very small and thus we could think about it linear terms. However, on second thought, that's not the case and it's very much the opposite. Large plates is actually where it makes a bigger difference. So, I looked around a little bit and found this interesting resources:

explaining euler pole
euler pole movement applied to the boundary between north american plate and pacific plate

I also thought of a way to picture this with PS (or Gimp):
- create a layer on top of the the map and place a solid color shape exactly fitting the plate you want to look at
- on another layer draw a little cross to mark the euler pole of that plate
- under <edit>, select the option rotate - a small cross with a circle appears in the middle of the selection
- move that circle to the position where you placed the cross and then rotate the shape
- this allows to experiment with the plate movement and to figure out where subduction, transform and crust formation is happening

(this is an extra effort to get things right and may or may not end up to be useful, I haven't quite experimented enough with it yet - I also suspect it won't work well on plates too close to the poles)

I tried this out in gimp. It adds a whole lot of complicated. Depending on the rotation, I created divergent boundaries where I had none before. I kept this limited to only my largest plate but I realize that I have to be careful otherwise divergent boundaries would spring up all over the place.

I have a question about the Euler poles. From my understanding the Euler pole is an axis of rotation independent of the earth axis of rotation. It is around this axis that the a body moves across the surface of a sphere. Because it is circular the body would a some point reach it's starting position if no other bodies interfere.

on a flat surface couldn't this be shown with a simple compass, it won't be mathematically accurate but for the general idea it should work seeing that rotation is faster farther from an axis of rotation.

Or am I so completely off that it is better if I stop typing? I'm gonna stop typing.