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Posted: 15.07.2003, 12:20
On its way to you now.
Posted: 16.07.2003, 02:57
Wow the texture is just amazing!
I have some questions about it. I can see that New York state (where I live
) is not covered up by the ice sheet. Does that mean that it wasn't covered up in around 18000 BCE? I know that it was covered at some point. That's how Long Island was created. Enough stuff was left so that it was still above the sea level when the ice melted. And I have seen big rocks in the Adirondack mountains that were left by the glaciers. One was as big as two cars stacked up!
It would be nice to have different textures for different times but would that be a lot of work? How different was the sea level when the glaciers were at their maximum extent? And is the ice south of the Bering land bridge floating on the sea? I thought so because not all of Siberia was covered up. Or is it not done there? Thanks so much for creating a beautiful texture.
Posted: 16.07.2003, 09:18
The map I am using is not in the greatest resolution. Grant had to send me a much improved section for me to rework the lakes near England. I am aware that the glaciers are not low enough on the east coast of North America. Again the map being at such a low resolution has a great deal to do with that and it being sinusoidal causes a great deal of distortion at the edges.
The texture you see in the screen caps is just a saved .png copy of the original .psd file that has many layers in it. All I have to do is open the .psd in Photoshop and do a little tweaking to ice cap layer to get the ice were I want it. By working in layers instead of one static image gives you the ability do such changes without effecting the rest of the texture.
One thing no one as yet has mentioned is that there seems to be a slight misalignment in the snow texture, it gives the snow a blurred look. I didn't notice the problem till I had it loaded into Celestia. Sometimes checking your work in a 3D environment gives you a whole new perspective and it sometimes shows you were you screwed up.
Now as far as I can tell from the map I have is that most of Siberia was almost completely ice free except for the most extreme northern parts. My thinking on this is that during the ice age there was very little precipitation over Siberia versus North America witch is very heavily covered in ice. One interesting fact that I noticed in making this texture is that the placement of the ice caps is in almost the same location that the Auroras are. The Aurora Borealis hangs low over most of North America, Greenland and then starts to go farther north near Finland and then it stays in the Artic circle till it comes back around toward North America were it drops down again. The same thing seems to happen in the south. Most of the southern ice cap stayed below South America and just past Africa it start going north. It goes almost as far as Tasmania and then starts to go lower as it it gets close to South America again. This is the same path the Aurora Australis travels. Interesting isn't it. I will plug in my Aurora nightside texture and take a few screencaps to show this.
Posted: 16.07.2003, 10:33
Here are those Aurora shots that show how the ice almost seems to follow its limits.
Kind of interesting!
Posted: 16.07.2003, 11:32
Those are beauties... Keep them coming
Posted: 28.07.2003, 07:15
I dident know that we had electricity during the ice age
just joking, just looks strange with city lights during an ice age
And for the textur itself: HOLY !@#$, PUT WHAT YOU HAVE SO FAR UP FOR DOUNLOAD< IT LOOKS FANTASTIC!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
P.S. Thats 100 !'s, and no I didnt cheat and use copy paste, thats how much I love that textur!
possibly incorrect data?
Posted: 28.07.2003, 09:59
HI all, long time lurker but first post here:
I have looked at your screenshot. GREAT JOB!
Seems to me, from the maps I have, that your source map is not very accurate in the eurasian part:
I wish I had a scanner to email the maps to someone; I try to describe the differences.
The black sea did exist at the time, was simply smaller but well-feeded from rivers of east europe.
instead of marmara sea, a big river connected black sea to egean sea; another VERY big river or a long channel connected caspian sea, that in 18'000 bce was MUCH LARGER than now ( for a level, consider the actual world sea level height and fill the caspian sea to that level; the azov sea was not open to the south as now, but to the west;
Aral lake, Baikal lake and Balhas lake were Much bigger than now; another big river connected aral lake and caspian sea; if you had a boat, you can go from syrdarja to atlantic ocean!
Look now at Iran desert; there are some depressions now with salt desert or small rivers; at the time were filled with water forming big lakes ( if you try to render these areas, you should find a good atlas and look at the heights level; this can help you ).
Also, the siberian rivers found no way to the sea, filled with ice; so, the water formed a 1'500 km wide lake in south siberia ( roughly between Novosibirsk and Celjabinsk ).
I'm sorry I can't give you maps of the zone at the time; someone with a good historic atlas AND A SCANNER, DAMMIT! can do this for me?
Best regards, and keep with the good work
Posted: 28.07.2003, 15:17
Yes, Scotese doesn't seem to have devoted much time charting the various epicontinental seas in his paleoatlas - but he was primarily concerned with the movement of continents.
I've e-mailed Don a map of the Central Asian drainage in 18000 BP which is a pretty good match for what you describe
. The Ob Gulf is ice-dammed and floods back into Siberia, eventually finding its way to the Aral basin, which floods in turn and breaks out west to the Caspian. The level of the Caspian (now draining much of western Siberia!) rises to higher than present-day sea-level, and then finds drainage westwards into what's at present the Azov Sea, but which at that time was a flat valley above the level of the Black Sea. Black Sea, maybe fifty metres lower than today, is still higher than the water level in the Mediterranean, and so drains by a succession of waterfalls and lakes along the present Bosphorus, Maramara and Dardanelles.
But are you sure Baikal was bigger? It's a very
steep-sided depression, and would have to be massively deeper to show much increase in area.
Posted: 29.07.2003, 08:02
Work on this texture is suspended until further notice. When I can find better data on the time period I will continue the work. I am getting and reading some conflicting information. When that happens I suspend work until I have verified facts. Sorry but thats how I do things. I refuse to release something till I am happy with it.
Posted: 29.07.2003, 16:44
How do you make a map like that? It's obviously far more than just painting a big patch of white in Photoshop.
Posted: 29.07.2003, 18:58
Don. Edwards wrote:Work on this texture is suspended until further notice. When I can find better data on the time period I will continue the work. I am getting and reading some conflicting information. When that happens I suspend work until I have verified facts. Sorry but thats how I do things. I refuse to release something till I am happy with it.
I'm really looking forward to seeing this texture, Don. Don't wait too long . . . I appreciate that you want to do more research and get the texture as accurate as possible. But our knowledge of ice age geography is incomplete and will continue to be refined--accept that your texture will necessarily always be a something of a work in progress.
Posted: 29.07.2003, 20:44
I am sorry if I have upset you; I was simply trying to contributing using the informations i have. If the map is "A work in progress" i presumed can be given some idea; if is bad for you, don't consider it, but your work is precious; don't leave us whitout it.
You are right; you need more precise sources of data,
Try looking at this:
Siberia - the land of wonders
and look at the sections;
The last Glacial Epoche
--- Rivers and lakes ( map of siberian glacial lakes )
--- The Siberian Lake ( more detail of the west siberian lake )
--- The last great glacier ( the icecap seen from north pole )
I hope these are helpful.
PS: granthutchison, probably you are right about bajkal lake,the shape of the region is unlikely to have stored far more water tan today, unless the lake was frozen.
Posted: 30.07.2003, 05:45
Sergio and Chris,
I am not mad at all. I simply want to have some verification of a few things.
The info you posted and what Grant sent me gives me something to work with. The problem I am having that at this time the Black Sea was much smaller than it is now. Also it laid at a much lower elevation. The problem is the info you stated and what Grant sent me contradicts a few things that come to the surface in the last few years.
1. You stated and according to the map Grant sent me says that the Black Sea was emptying into the Mediterranean Sea. But if the Black Sea was at a much lower level than it was today water had to flow uphill as the entrance to the Black Sea was above the water level at that time.
2. According to research being done by the Ballard Institute of Titanic fame, I think that is who is doing it. During the time of the last ice age the Black Sea basin was allot less full than today. They are looking for ancient settlements under the water there and they are thinking that the mass flooding of the Black Sea basin was the whole key to the old biblical flood theory. So taking all this into account I will tweak things just a little. But I am going to keep the Black Sea basin mostly dry but with a larger lake in the middle. This should take care of a few of the issues. I will work with things a little more as time goes on.
Posted: 30.07.2003, 07:11
Nice work Don, looks great. Im looking forward to the download.
Posted: 30.07.2003, 13:47
A suggstion: you might want to include a document with your map(s) as you make them available explaining the various choices you made and referring to the source material you used to make the decisions. That way (one can hope) there might be fewer people complaining about one detail or another.
Posted: 30.07.2003, 14:43
The Black Sea was at its recent lowest about 6000 years ago, when it was indeed >100m below its current level, and couldn't have drained into the Med - but that corresponds to a time when the Ice Age was mostly over and the Siberian ice-dam was no longer diverting water south to fill it. That's also the time frame that Robert Ballard claims to have discovered submerged settlements from.
The Bosphorus is about 35m deep at its shallowest, and you can imagine that there might be a deeper river bed buried under the present sediment - so a Black Sea 35-40m lower than today would still be able to drain over the "Bosphorus sill", and would still leave the Azov Sea and the present shallows around the Volga delta high and dry, as they appear in the map I sent you.
So I think there's internal consistency here - when Siberian water flowed south, it filled the Black Sea just enough for it to start pouring through the Bosphorus as a broad river, on its way downhill to a Mediterranean that was about 90m lower than the Bosphorus sill. Later, the ice in the north disappeared, the Siberian rivers assumed their present drainage, and the Black Sea level fell until it becomes a landlocked lake like the Caspian. Later still, as the Mediterranean rose towards its present level, it poured back across the Bosphorus sill and filled the Black Sea, causing the flooding that Robert Ballard is investigating.
Posted: 30.07.2003, 18:54
Yes this is quite right. the actual depht of the Dardanelles is between 50 and 90 meters, and there is geological evidence of thick sediments coming from Black sea toward Mediterranean. at the southwestern end of the Bosphorus the river formed an actual delta in the Marmara sea, formed by sediments of european rivers; now the delta is under the sea and covered by marine sediments coming from the Mediterranean.
Posted: 31.07.2003, 02:20
Ok I will try and integrate this info as best I can.
Posted: 24.09.2003, 08:52
Well I think I have left this area long enough without an update so here it is. I have tweaked the texture a little more. I was getting some strange white haze effects in one of the layers. So I managed to clear that out. I worked on North and South America some more. I thing South America is nearly finished. I still have a little work on North America. Asia is almost finished as well. Things that I feel are finished, Africa, India, Indonisia and Australia. The last major thing to finish is Europe. Once thats done it will be a simple further adjustment of color values and I think I can call this texture finished.
One thing that was pointed out was the lack of glaciers over New York and the New England area. Thats fixed. So here are some obligatory shots to show the improvments.
Sorry no Europe pictures as there hasn't been any real changes there as of yet.
Oh yah, there is something else I think I just might make an atemp at.
EARTH 65 Million Years Ago!
Posted: 24.09.2003, 09:48
Really great maps!
There's a site
where you can see how vegetation zones have changed during ice age. For example Amazonian and African rain forests were much smaller.