The Distribution Of Deserts And Mountains On A Fictional Alternate Earth.

[CroMagnon]

My story's world, Axis Earth (just called earth by the inhabitants), has been built from scratch from tectonic plates up. I'm sure I made some mistakes because I can only do so much math, but I at least tried to make my topography follow the plate boundaries. AE's genesis paralleled our own- exact same size, distance from the sun, axial tilt, etc- until the crust began cooling, breaking up, and moving. Most of the differences between our earth and this alternate one are thus only surface deep. I imagine that's still quite a bit of a difference. So these particular questions are concerning the placement of such things as deserts, swamps, faults, mountains, forests, etc. I've studied these things a lot, otherwise I wouldn't care where I put my damn mountains, but I'm not about to rely on my outdated 80s-textbook hoosier high school education. Thanks in advance for any help!

 

1: Are my plate tectonics even viable? I know that on its own is a vague question no one can answer without seeing my map, so I'll try to elaborate what I mean without rambling: plate tectonics started billions of year ago, yes? Not today? Well my tectonics map for AE only reflects the state of the plates today. I can't map out the movements of the plates over the course of billions of years, the math just to grid the map was hard enough, so I don't have any old mountains or faults where seismic activity has long since ceased. So how would I retroactively place older orogenies, cratons, basins, etc in relation to my current plate boundaries without mapping out the movements of my plates from the beginning? Or phrased differently, how far back can geologists clearly retrace the movements of tectonic plates based on the current location of geological landforms?

 

2: How tall can a mountain grow? A measly 10,000 feet more than Everest? Any higher? How deep can air-filled caverns (I never said breathable descend into the crust or mantle? Yes I'm talking like that underground magma cave in The Core, somewhere a person could walk if they wouldn't be vaporized.

 

3: What are the different types of mountains, plateaux, and valleys by how they are formed? What is the difference between a valley and canyon? Would mid-oceanic ridges on any earthlike planet be connected like ours, or is it an otherwise unlikely occurrence? If most rift valleys are formed in the ocean, what determines whether the continent cracks open instead, like in East Africa?

 

4: How much is climate affected by topography? If a planet had the exact same size, axial tilt, distance from the sun, etc as earth, but had mountain ranges and landmasses in different places, how different would our weather be? How would the Ice Ages be affected? What all factors determine where such environments as deserts, forests, and swamps are distributed across the globe? I've noticed a theme on our planet of mountains and deserts being on the west of continents. Is there any particular reason for this? What determines whether the coast is rocky with cliffs or a smooth sandy beach?

 

I hope these aren't too many questions, I just find I think better if I discuss a topic as a whole rather than trying to break up a concept into individual threads. The concept of this thread being general worldbuilding. I often find I wonder either more or less than I thought, so setting out to ask one or two pertinent questions is essentially pointless. Everything connects to another in my writing. I appreciate any help with these questions, as well as any other often-overlooked geological/meteorological rules of thumb I may find interesting. Thanks all for not being jerks like at the other science forum!