# How likely is it for a planet to have belt-shaped continents?

Is it possible for such a planet to have main continent(s) shaped as following?

Apparently an equatorial belt is possible to form from ring debris, but it seems to depend on the planet having no atmosphere. So I wonder if there are alternatives.

• Please edit the question to limit it to a specific problem with enough detail to identify an adequate answer.
– Community Bot
Commented Oct 16, 2022 at 16:19
• Welcome to worldbuilding. As you can find in the help center, we want to have 1 specific question per post. "What if X happened?" is overly broad, and you have 3 of them.
– L.Dutch
Commented Oct 16, 2022 at 16:22
• related reading: worldbuilding.stackexchange.com/questions/94256/…; this is pertinent only to your equatorial belly band continent. Answer though contains speculation about ocean mixing which is relevant to circumferential band continent of any orientation. Commented Oct 16, 2022 at 17:09
• Thank you. Next let's work on your expectations and needs. You'd be surprised how many people come here asking whether or not something is possible as if modern science has all the answers. It doesn't. Not by a long shot. If you're asking, "is this possible in Real Life?" the answer is, "maybe, does that matter? Per the help center, our goal is to help you develop an imaginary world." If you're asking whether or not this meets suspension-of-disbelief, then you've answered your own question (the possibility in any circumstance justifies the probability in others). So, why are you asking?
– JBH
Commented Oct 16, 2022 at 18:09
• Possible and likely are two different things, unless it is important to the story to describe the how, the real universe is sufficiently large that planets like these will exist somewhere. Our planet has a roughly circular continent almost exactly centred on the southern pole, and a roughly circular ocean over the north pole, similarly centred, how unlikely is that?! Commented Oct 17, 2022 at 14:27

## 2 Answers

One way is to have the planet spinning faster in the past and then have something slow it down in the recent (few million years) past. maybe capturing a moon. water will rebalance faster than rock. so the equatorial bulge of water will lessen faster than the rock so you get a few million year of higher equator. you can't do this with oceans as deep as earth's but it works fine with a shallow ocean.

your planet will have a LOT of earthquakes though. Also this only works for a single "belt"

• That would have been my suggestion, too. One way it could happen is if the planet has a very large moon - larger than our own. Then, tidal effects would slowly reduce the planet's rotation, transferring energy to the moon, which would rise to higher orbits. This is actually happening Earth, and eventually, the Earth and Moon will be tidally locked. After this, the Moon will slowly lose momentum orbital attitude, eventually reaching the Roche limit and break up into a ring. Commented Oct 17, 2022 at 8:07

You can imagine continent formation to be like granite soap bubbles forming on the surface of a basalt kitchen sink. I you can make lines of bubbles form in any way, then you can produce belt continents.

This might come about when a continent floated into a subduction zone, and the granite spread out along the edge of the zone. You have something like that along the California coast line, but you don't see it as a belt because there is more continent on the other side of the fault.

So, not impossible, but hard to arrange.

• Could you explain "granite soap bubbles forming on the surface of a basalt kitchen sink"? Commented Oct 17, 2022 at 10:18
• Sure. This is actually from The Story of Earth, and I highly recommend that book if you want a deep dive. In the beginning, all things were basalt. Granite has to be generated later in a planet's history. It is formed in the high pressure chaos of subduction zones, and is less dense than basalt, so it winds up floating to the top over a period of hundreds of millions of years. The continents are basically clusters of granite floating on the basalt crust like sponges. That's why we get continental drift instead of the planet making new continents. Did that help? Commented Oct 17, 2022 at 17:12
• you can't actually put the continents anywhere you want, several forces interact to control where continents end up and a long line is not an option. how continents form forces clisters that break up in certain ways.
– John
Commented Oct 17, 2022 at 20:28
• @John, True, but that's why I suggested the sink experiment, let him figure that out for himself. Commented Oct 17, 2022 at 22:29
• @RobertRapplean and sink won't work you are talking about a spinning ball
– John
Commented Oct 17, 2022 at 22:55