Early Earth Cracked Like an Egg

[Breaking Earth’s shell into a global plate network](https://www.nature.com/articles/s41467-020-17480-2)

Our spherical shell models show how a tectonic plate system can evolve from shallow processes. None of the plate boundaries here are actively triggered by deep processes, and a fracture mechanism allows for lithospheric rifting on a global scale.

Related video:
https://www.youtube.com/watch?v=iZhOq8KgWAk

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@PDPrice I wondered if you had seen this article. It was late at night when I came across this video so I wasn’t really coherent. Commenters here said a global flood would produce too much heat. I wondered if these models prove that wrong and also show that not very much water was needed.

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@thoughtful what do you think of this? GPS, Radiodating, and Plate Tectonics

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Some of these same topics are addressed in a very interesting series of articles beginning at:

The series is a reply to Answers in Genesis’ ten best evidences for a young earth.

I don’t want to weigh you down with a long reading list (and certainly don’t expect you to comment on all of them) but you might want to bookmark the link for future reading on these topics.

Meanwhile, if @Pdprice has a favorite or two among the AIG young earth evidences list, I could launch a new thread to discuss them.

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But you or @swamidass are not interested in the new modeling? I was wondering how much it challenged previous scientific thinking. It appears it’s a big deal, but since I have been studying cosmology and not plate tectonics, I have no idea how big of a deal it is.

Of course it’s interesting. I don’t think it does at all what you need to make YEC work with what we know of geology. I’m curious @Joel_Duff and @davidson’s thoughts of course.

Of note @thoughtful, look at the abstract:

The initiation mechanism of Earth’s plate tectonic cooling system remains uncertain. A growing consensus suggests that multi-plate tectonics was preceded by cooling through a single-plate lithosphere, but models for how this lithosphere was first broken into plates have not converged on a mechanism or a typical early plate scale. A commonality among prior efforts is the use of continuum mechanics approximations to evaluate this solid mechanics problem. Here we use 3D spherical shell models to demonstrate a self-organized fracture mechanism analogous to thermal expansion-driven lithospheric uplift, in which globe-spanning rifting occurs as a consequence of horizontal extension. Resultant fracture spacing is a function of lithospheric thickness and rheology, wherein geometrically-regular, polygonal-shaped tessellation is an energetically favored solution because it minimizes total crack length. Therefore, warming of the early lithosphere itself—as anticipated by previous studies—should lead to failure, propagating fractures, and the conditions necessary for the onset of multi-plate tectonics.

It isn’t really challenging what we know of plate tectonics, but filling in some details about how the processes we see began.

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The terms here used are like Greek too me, as physics was a few months ago. Lol, I need a break from science for a while or my head will explode as I keep finding one new interesting thing after another and then get little sleep. :see_no_evil: I just enjoyed the video that explained the authors only needed to add an extra kilometer of depth to the earth’s surface to add enough pressure to get plate tectonics.

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It appears that the “shell” of Venus is locally cracking as we speak, involving mechanisms and structures that are in some ways similar to the early Earth’s primative lithosphere, and in other ways quite different.

A recent article in Nature Geoscience reports recent research.

From the abstract:

In the absence of global plate tectonics, mantle convection and plume–lithosphere interaction are the main drivers of surface deformation on Venus. Among documented tectonic structures, circular volcano-tectonic features known as coronae may be the clearest surface manifestations of mantle plumes and hold clues to the global Venusian tectonic regime. Yet, the exact processes underlying coronae formation and the reasons for their diverse morphologies remain controversial. Here we use three-dimensional thermomechanical numerical simulations of impingement of a thermal mantle plume on the Venusian lithosphere to assess the origin and diversity of large Venusian coronae.

The link above leads you to the abstract; the full article is paywalled. PM me if you are more interested and I can send you a pdf of the full article.

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