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davidson16807 / tectonics.js

3d plate tectonics in your web browser
http://davidson16807.github.io/tectonics.js/
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Flat Earth Start #30

Open redferret opened 6 years ago

redferret commented 6 years ago

Based on what we know the Earth was mostly flat covered in oceans after the Hadean period. Subduction should allow for Volcanoes to add landmass (if it doesn't already) to grow the seeds for continents later in the life of the planet. Larger basalt flows could also help add to continental formation as well. Hot spots could help grow islands like the Hawaiian islands or even super volcanoes like Yellow stone (hot spot under a continent)

davidson16807 commented 6 years ago

This all sounds reasonable.

Earth was mostly flat covered in oceans after the Hadean period

Could I get a source for this? This could be done easy by adjusting the hypsographic curve fed to WorldGenerator.

Subduction should allow for Volcanoes to add landmass

It does (look up "accretion" in the Lithosphere submodel). The model assumes that continental crust is a conserved quantity, so volcanoes are used to feed subducted continental crust back into the system. We just need to tweak the control points fed to WorldGenerator so that continental crust is more evenly distributed across the surface. The continental crust should accrete into continents without any additional intervention.

Hot spots could help grow islands like the Hawaiian islands or even super volcanoes like Yellow stone

Hotspots don't generate the felsic crust that's needed to form continents. However, this is something I want to add. It amounts to adding a new crust delta within the Lithosphere class and specifying its behavior.

Larger basalt flows could also help add to continental formation as well

Like the Siberian traps? I'm not sure how we'd go about modeling that.

I think we want to consider implementing the startup menu discussed in issue #19 along with these changes. I expect some people might just want a quick world to start with, whereas others might want to simulate from the beginning.

I personally think it'd be cool to see a planet before the crust solidifies and the oceans precipitate, just like SimEarth. I'd love an excuse to model black body color from molten crust. :grin:

redferret commented 6 years ago

Here's one source about earth around 4.4 billion years ago. I also attended a lecture at the School of Mines where the professor talked about this as well.

https://phys.org/news/2017-05-earth-barren-flat-billion-years.html

redferret commented 6 years ago

"Hotspots don't generate the felsic crust that's needed to form continents" Ah but during one of the extinction events that formed the Siberian traps, it added a huge amount of land mass to the continent. Flood basalts like that can happen every few hundred million years.

davidson16807 commented 6 years ago

Well yeah, I know it has a noticeable effect on landmass and we should consider it if we have a way to model it, I'm just saying it creates a bunch of basaltic crust. That stuff is probably going to go back into the mantle when the crust subducts, whereas continental crust gets accreted back out to the surface.