The worst river violations ever...

[Juggernaut1981]

I'm sure the other post is comprehensive, I haven't read it for its physics/hydrology/chemistry content.

**Puts on his Chemistry/Physics Hat**

All liquids move towards a point of "lowest energy" (i.e. closest to the centre of the relevant planet) by the path with the "least resistance".

Least resistance has two parts: descent rate and the ability for the water to alter its surrounds. Given the options of trying to make a gully in granite or in nice loose black soil... the river will move to the soil and then take the path which maximises the descent and takes the path through the most "movable" material.


Take an example with a big mountain range. The river will move fairly straight through natural cracks in the rocks (opening them up further... see The Grand Canyon) and take very few sharp turns, rarely double up on itself or anything similar without a VERY VERY good reason.

Once it leaves the mountains it entirely depends on the slope to the ocean. If the land is basically flat (barely ANY slope at all) the river will wander all over the place until it finds the path with the most easily moved material.

My advice: Use Google Maps to look at China. Plenty of rivers. They all start in mountainous areas, flow straight for a long-ish period of time and then start straying when they hit the wide flat lands across most of central and coastal China.

Deltas = wierd places where rivers get confused and hedge their bets by splitting and taking as many paths as they can push water through. Nile River Delta, end of the Mississippi river...

Australian Rivers = we have a near monopoly on the concept of a "sand river". There is a river flowing, but it's underneath/through 5m depth of sand and only really flows above-land when you've REALLY got water flowing.



As an explorer, if you ever got lost, the solution to getting to somewhere nice and hospitable was find a river and follow it. Eventually you will hit the coast. Don't try this trick in Australia... it doesn't work quite right and we have the dead 1800s-era explorers to prove it.

[Gamerprinter]

OK, Juggernaut, have some REP for that bit science on rivers!

My curious question now regards the Yucatan Peninsula, and the Island of Cozomel. I've been to Cancun, Mexico, on vacation a few years ago, having recently (at the time) learning about the propensity of underwater rivers in southern Mexico. The island of Cozomel (largest island off Mexican coast, very near Cancun.

Most of the Yucatan is extremely flat, but there are almost no surface rivers there. Sinkholes everywhere. Underground rivers everywhere.

I visited a "park" that contained a sinkhole right near the coast, about a half mile away from the sea. Fresh water rose from the sinkhole and formed a short surface river called a "Ria" that reached the sea.

Cozomel is really not that big, yet underground rivers course meandering around the reaching the sea.about 5 meters under the surface.

I've always wondered about the science regarding that... Can anyone answer, Juggie or Waldronate?? It seems almost bizzare.

GP

[Coyotemax]

Cenotes! (underground caverns/sinkholes with pools or rivers running through them)

wonderful places from what I understand. I'm going to the yucatan for our 10th anniversary, I'll b taking lots of pictures so you can marvel over those. if I learn something neat about them while I'm there I'll let you know (i suppose I could google-fu, but i think it'll be more fun to find out while I'm there)

[NeonKnight]

OK, Juggernaut, have some REP for that bit science on rivers!

My curious question now regards the Yucatan Peninsula, and the Island of Cozomel. I've been to Cancun, Mexico, on vacation a few years ago, having recently (at the time) learning about the propensity of underwater rivers in southern Mexico. The island of Cozomel (largest island off Mexican coast, very near Cancun.

Most of the Yucatan is extremely flat, but there are almost no surface rivers there. Sinkholes everywhere. Underground rivers everywhere.

I visited a "park" that contained a sinkhole right near the coast, about a half mile away from the sea. Fresh water rose from the sinkhole and formed a short surface river called a "Ria" that reached the sea.

Cozomel is really not that big, yet underground rivers course meandering around the reaching the sea.about 5 meters under the surface.

I've always wondered about the science regarding that... Can anyone answer, Juggie or Waldronate?? It seems almost bizzare.

GP

Could be the Yucatan Peninsula is the remnants of that GINORMOUS Meteor Impact that spelled the end for our favorite dinosaurian friends

[Gamerprinter]

The Yucatan is mostly liimestone. Tropical rainforest or at least jungle at the surface, thus rainfall becomes acidic and "melts" holes into the surface and carves channels underneath. Holes enlargen and become sinkholes (cenotes) and dozens if not hundreds of unexplored rivers carve the underground of the Yucatan. Underground rivers join, eventually reaching the sea. Many rivers reaching the sea separately. Some as the "rias" mentioned in the above post, some as partially submerged tunnels reaching the sea.

Of course, closer to the sea, the upper portion is fresh water, while the lower portion is salt water. Most life, live in the salt water. Unsure of the technical name, but like a thermoclyne, there is a defined separation layer between the salt and fresh water. Salt water is blurry, while fresh water is clear. If swimming in the fresh water portion, crossing into the salt water causes the waters to mix and vision to become cloudy. Due to large and small hole, almost invisible sinkholes many chambers have that rise above the water level.

From discussion with friends and some google-fu.

Could make an interesting subterranean river system map with exposed sinkholes and of course Mayan ruins/zigurrat pyramids hidden in jungle at various cenotes...

GP

[RobA]

Unsure of the technical name, but like a thermoclyne, there is a defined separation layer between the salt and fresh water.

Think it is a Halocline.

[EDIT: checked at wikipedia: http://en.wikipedia.org/wiki/Halocline]

-Rob A>

[waldronate]

Karst terrain is fun. Sinkholes, rivers that disappear underground, and rivers that appear full-blown out of a cliffside are all examples of the fun things that happen there. Turkey and Greece are examples of karst terrains where those features have played a major role in history. The Kentucky area with its famous caves is another example. Maturing limestone terrains are always full of surprises.

[Gamerprinter]

Thanks for the proper vocabulary, Waldronate (haven't REPped you in awhile, so I'll do so now!)

I know that Japan has several extensive limestone cavern systems as well, though I hadn't heard of any until a quick google-fu said there was...

So, I think (agreeing with Waldronate) Karst terrain is fun. So I think I'll work on a Karst terrain map with above above ground view of map area and underground reveal of map area showing underground river systems - eventually reaching the sea, then developing a complex adventure module to utilize that terrain effectively for more Kaidan fun.

I was thinking of working on a Karst terrain as a side project, but since I am deep in Kaidan development, why not continue and try a Karst terrain with my current project and make it fun, useful and profitable!

That's my next project I think. (I do eventually want to involve my undersea map, and may be able to connect the two - Karst + Ryukyo.)

GP

[zenram]

Wow, that's something, i think it's the part that keep me away of drawing an area or world maps, there are so much research to do. The other day i was thinking in to draw a continent map and was so surprised about all the thing to take into account....

Well, this will help me a little more. Thanks XD
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[Lwaxana]

Most important things to remember I think is that rivers run downwards and go from smaller ones to forming wider ones and there are usually at least 2 large rivers on a continent. Up to now no one complained about my rivers but i had a few people pointing out my weird continent design once

The info above is very interesting though and might help me in my plan for an underground city.