[WIP] World of Aduhr

[Charerg]

Right, so the final high-res map is finished (if you consider 1576x710 high anyway...). I made quite a few revisions to the interior, so it took me a bit longer than anticipated. And of course you could keep fiddling with the details ad infinitum, but in an attempt to rein in the perfectionism a bit, I've decided to call this version finished.

So, here's the map with Azelor's elevation key:
AzelHMap.png

And with the "Char elevation key" seen previously (this time there's enough resolution to even include the key with the map):
HMap Layered.png

The above with gradual transitions:

 

HMap Gradual.png

Note that the lower elevation has been capped at -150 metres min. and 6250 m max. here, so the lower (and uppermost) layers of my elevation key are unused in this scheme.

Here's how the greyscale height map looks on the globe:
AkanNova Orthogonal.PNG

As I mentioned, I made a few updates to the geology of the subcontinent's interior as well. I'll add that to this post when I have the time.


Edit: the Akanrian Geology

About that geology update, my previous geologic update had the ages of the older fold belts as follows:

~1100 Mya: Central Akanrian Fold Belts
~850 Mya: East Akanrian (aka Tamanaro) Fold Belts

I expanded this somewhat by splitting the West and East Akanrian crations into two component blocks. The W. Akanrian Craton's southern portion is now a separate block (called the Uiruno Terranes) that was accredited to the craton perhaps ca. 1500 Mya. So, there's the remnant of an ancient fold belt there. The E. Akanrian Craton has been split into two cratons: the southern one is called the Ingilo Craton. The two pieces collided ca. 1300 Mya, forming the Ingilo Fold Belts.

In addition, there is an ancient failed rift responsible for Akanosuwa, the large interior lake. The Akanosuwa Rift formed at an age close to the Tamanaro Fold Belts, so perhaps 900 Mya. All these ages are extremenly rough of course, as I haven't modelled the tectonics beyound 200 Mya (which was covered in the tectonics update about a year ago). As a real world inspiration I had the North American Midcontinent Rift System (about 1100 Mya), responsible for creating the basin occupied by Lake Superior.

So, here's the updated geologic stuff with a nice relief map from Wilbur (I omitted most of the younger formations from this as those were covered in the previous geology update):

GeoMap.png

Oh, and I should mention that I changed the former East Akanrian Shear Zone into a more complex fault complex. Previously I had it as something similar to the Alpine Fault. I realised that this kind of primarily transpressional transform faulting doesn't make any sense in these circumstances. So now the faulted area has pull-apart basins in areas where a "releasing bend" causes extensional stress (transtension) and mountains where a "restraining bend" causes compressional stress (transpression). Ofc this transform fault became inactive about 150 Mya, so I'm a bit on the fence whether I should've eroded the region into little lower elevations. But like I said, I don't want to get too stuck with the details, so I decided to leave it as it is.

[Ilanthar]

I really like that relief map. Interesting landscape, rifts are generating fascinating ones.

[Charerg]

I really like that relief map. Interesting landscape, rifts are generating fascinating ones.

Glad to hear that it looks good! Overall I'm pretty happy with the result too.

However, as another mini-update, after taking a few weeks off Aduhr and having a "fresh look" at the piece, I have to say there were just a few details bugging me about the overall elevations. So, I ended up "opening the stomach" of the subcontinent a bit more, so there's a larger lowland basin. In the process, the courses of the major rivers also shifted a bit (since Wilbur rarely generates the exact same courses twice). I ended up largely flattening the highland region of the Uiruno Fold Belt (well, that was supposed to be really ancient anyway).

Here's the new version (call this "final II", though this time I intend this to truly be the final one):

Height maps:
HMap final_ii.png

HMap azel_ii.png

And finally the relief map (this time without the geologic stuff):
Geo_v2_shaded.png

Edit:

Ok, that wasn't quite final yet. I changed the drainage system a bit and applied a bit more precipiton erosion in Wilbur. Here's the (hopefully final) "final 3" map (this time the gradual version so the drainage network is easier to spot):

HMap f_iii.png

[Tiluchi]

Charerg, I can only echo Pixie and say that it's truly inspiring to see how much work you put into your geology (among other details). My head is spinning from all the thought and research that went into this- and this is coming from someone who has 24 geology-related tabs open on their computer for their own project!

Just a question- is there a coding behind the coloring of the tectonic boundaries you drew in that geology map? I can tell what they are of course, but I'm curious what the colors are. Is it age-related? Asking in particular because I'm curious about the geology behind the very interesting-looking T'kalo group...

[Charerg]

Charerg, I can only echo Pixie and say that it's truly inspiring to see how much work you put into your geology (among other details). My head is spinning from all the thought and research that went into this- and this is coming from someone who has 24 geology-related tabs open on their computer for their own project!

Just a question- is there a coding behind the coloring of the tectonic boundaries you drew in that geology map? I can tell what they are of course, but I'm curious what the colors are. Is it age-related? Asking in particular because I'm curious about the geology behind the very interesting-looking T'kalo group...

Oh, yes, there is some method to the madness though I realise I totally forgot to explain the colours. The T'kalo region follows the standard colours since those are actual active present-day tectonic boundaries (so, green=transform, purple=convergent, blue=subduction). The rest are ancient fold belts going from purple=oldest to light blue=youngest (though even the youngest fold belt is maybe 750-500 Mya old, I haven't worked out the exact details regarding their age).

The Akanosuwa Rift has about the same age as the Tamanaro Fold Belts (just slightly older). Originally I had it as ~900 Mya, but now I think 800-600 Mya is a bit closer. And the East Akanrian Fault Complex dates to the breakup of Panwara, so 200-150 Mya.

[Charerg]

Here's another very minor update. I haven't started work on C. Eocidar yet, but I made another minor change to Akanrias, namely somewhat lowering the elevations in the interior: those ancient fold belts were a bit too tall overall. So, here's the "final iv" (this time the layered version):
Fmap_tier_ii.png

The average elevation for the subcontinent is 405 ~400 m (this excludes everything west of the Great Akanrian Trough), although that number is a bit rough since this isn't an actual equal-area projection. It's surprisingly difficult to find accurate data about the avg. elevation of Earth's continents. I've found one source stating the avg. elevation of Australia as 244 metres, another claims it's about 300 m, and a third has a figure of 330 m. Same thing for Antarctica, one source says ~1600 m, the next claims ~2000 m, and a third has a figure of 2500 m...sigh. It seems either the internet is full of wildly inaccurate data, or geologists really need to get their math checked.

Anyway, since the 330 m figure for Australia is from a site maintained by the Australian government, I'm assuming it's the correct one. Europe seems to have a very similar avg. elevation to Australia, whereas the Americas and Africa are ~600 m average to give a very rough figure (again, I'm uncertain how accurate these figures are, but they seem about right).

So, Akanrias seems overall to be taller than Australia and Europe (which are 300-350 metres if my data is accurate), but lower than the rest of the continents. Which seems about right given that it's a fairly inactive area tectonically. I expected the avg. elevation to be somewhat lower actually, but I guess the large volcanic plateaus formed during the breakup of Panwara push it a bit higher than expected.

Edit:
Here's the "hopefully final version 4 of the final" in the Azelor colours:
Fmap_azel_ii.png

And the gradual version:
Fmap_grad_ii.png

[Pixie]

Hi Charerg

I also think this final version is slightly better than the previous final versions.

Indeed, your past fold belts were too noticeable. 200 million years can pretty much flatten any range, bar the hard core rocks. This leaves behind small thin mountains.

The one thing that bothers me (a little, and you don't need to value this) is the large deep river valleys that Wilbur carves in flat areas. Wilbur erosion model never drops any sediment downstream. This, however, is very important for topography. Where rivers slow down, like at the base of the mountainrange, a lot of sediments are deposited leveling the area. Your main rivers are crossing old regions, I'm thinking about the Ingilo craton, they should have levelled it much further.
The way I work around, when I goof around with Wilbur (not much these days) is that I raise the land slightly in those areas to be levelled every time I run an erosion cycle.


Still, this is my humble opinion about details. This is becoming a source of envy for me... but I can't stop looking at it anyway

Oh, and by the way, congratulations! Your tutorial about g.plates triggered me to revise the bits of tectonics I knew made no sense in my world... I'm on day 30 of a whole revision project (and enjoying it!) and still have nothing worth showing

[Charerg]

Hi Charerg

I also think this final version is slightly better than the previous final versions.

Indeed, your past fold belts were too noticeable. 200 million years can pretty much flatten any range, bar the hard core rocks. This leaves behind small thin mountains.

The one thing that bothers me (a little, and you don't need to value this) is the large deep river valleys that Wilbur carves in flat areas. Wilbur erosion model never drops any sediment downstream. This, however, is very important for topography. Where rivers slow down, like at the base of the mountainrange, a lot of sediments are deposited leveling the area. Your main rivers are crossing old regions, I'm thinking about the Ingilo craton, they should have levelled it much further.
The way I work around, when I goof around with Wilbur (not much these days) is that I raise the land slightly in those areas to be levelled every time I run an erosion cycle.

That sounds like a good idea. I actually thought about making the river channels less pronounced, but they seem to be fairly clear-cut when looking at Earth, even in areas which are ancient cratons (although it varies a lot between different rivers). Take a look at C. Africa:

Central Africa.png

The channels of the Kongo and Niger rivers are pretty clearly cut, although I'm not entirely sure about the mechanics behind it. The Kongo especially looks like it might have done some recent "downcutting", possibly as a response to epeirogenic uplift (the African superplume and all that, I'm sure you're familiar with the theories).

That said, you have a point that Wilbur's Incise Flow cuts relatively similar looking channels all over the map, and it would look better if there was a bit more variety regarding river erosion. I think I'll probably leave it as it is for now, since I don't want to get stuck too much with the details, but I'll definitely flatten out the Ingilo region at some point.

Oh, and by the way, congratulations! Your tutorial about g.plates triggered me to revise the bits of tectonics I knew made no sense in my world... I'm on day 30 of a whole revision project (and enjoying it!) and still have nothing worth showing

Good to hear that you found it useful! I think you should definitely post an update about the tectonics, if only to get some feedback, since that can always be useful. And yeah, tectonics can take a really long time if you go deep into the details. Actually I'll probably do a slight tectonics update myself at some point, since I have some new ideas that I want to incorporate (and in any case the old GPlates model is a bit outdated since I figured out most of the techniques demonstrated in the GPlates tut only recently). That said, I definitely want to create the elevation map of C. Eocidar first before tackling the tectonics update (though at the moment I'm only working at this sporadically).

[NadirtheFox]

Not much to say here: It all looks very nice to me. Not sure if I like the gradual scaling more than the non-linear one though, but I guess it is just a case of personal taste. Oh and I have to say that it is one of the best looking wilbured terrains i have seen so far... So I have a question: can you perhaps share with us some tips on how to make something like that? (And I know that every map is different and it may not work all the time... It is just nice to have a good starting point)
Keep on good work

[Charerg]

Not much to say here: It all looks very nice to me. Not sure if I like the gradual scaling more than the non-linear one though, but I guess it is just a case of personal taste. Oh and I have to say that it is one of the best looking wilbured terrains i have seen so far... So I have a question: can you perhaps share with us some tips on how to make something like that? (And I know that every map is different and it may not work all the time... It is just nice to have a good starting point)
Keep on good work

The Wilbur part of the process isn't anything special really, this is the usual sequence I used:
- Select Land Mask
- Precipiton Erosion (usually just 1x, though the final map has two rounds)
- Fill Basins
- Absolute Magnitude Noise (I used magnitude 20 in this case)
- Fill Basins
- Incise Flow (Amount 1.5, Flow Exponent 0.2, Effect Blend 0.5, Pre-Blur 0.5 were the settings used in the final)

You have to keep in mind the limitations of Wilbur though. Precipiton Erosion tends to really fill up lowland areas for example, which is why I only used a single cycle usually (even then I found myself lowering coastal areas and lowlands afterwards to compensate). It's still a very useful tool since you don't need to worry too much about the micro-scale details, allowing more liberal use of tools like generating clouds and painting with splatter brushes. Wilbur will take care of the micro-scale erosion and Fill Basins will connect everything up, eliminating any weird basins that might be left over from the generated/painted clouds. Likewise, Wilbur can create the drainage network for you, so you don't have to spend much effort creating the river basins.

But then, Wilbur won't actually create the terrain for you. It's a useful tool for making the job easier and dealing with the minor details, but the macro-scale details like the overall elevation distribution, shapes of mountain ranges, etc. need to be manually created. For that I used a variety of techniques. The first low-res version was largely just painted with a smooth brush with a generous amount of blurring. Of course I made full use of layers, like painting areas that I wanted to lift to a certain level in a "lighten only" layer, and so on. Later on I also used generated clouds as well as different splatter brushes to paint things in a bit more random fashion. Also, I suppose I should empasise the heavy use of blurring to make the elevations transition smoothly.

It helps to sketch things out to begin with and you also need to have some concept of how the overall elevation distribution should look like. I found the multi-scale approach helpful since it's very easy and quick to modify the low-res map that can be used as a testbed to try out different things and test how the overall elevation distribution should look. Then when moving on to higher resolution maps the emphasis was more on the details like the shapes of mountain ranges, which slopes should be steep, which areas should be higher, and so forth. Most of that was based on the geologic history I created for the region (so knowing which areas are fold belts, which are lava plateaus, where are the big normal faults left over from continents separating etc.). At this stage it probably helps if you've spent ages staring at a map of Earth and thinking about the geologic history behind various features.

Though as noted, I did end up changing quite a few things in the process of creating the map. It's always a bit hard to sort of "undo" previous work but I do believe that you have to be somewhat willing to make changes and experiment with different layouts in order to get the best result. It's somewhat risky in terms of working motivation though: if you end up re-doing an area a number of times and still aren't really happy with it, it can eat at your "mapping motivation". That's why it's probably better to first sketch things out and have some plan behind such changes before implementing them. I've lost count of the number of times I've changed something up only to find out that the new layout wasn't really better than the old one (or even outright worse).