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During the rotation of the Earth, a centrifugal force is formed, according to the actions of which ocean water should be collected at the Equator, forming a "hump" hundreds of meters high. However, there is no water hump on the Equator. The depth of the ocean does not depend on latitude, although there should be such a dependence. at the same time, the centrifugal force is sufficient to deform the shape of the earth from a regular sphere to a geoid!

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    $\begingroup$ I would simply say because of gravity. The centrifugal force is just a small correction to gravity $\endgroup$
    – Matteo
    Commented Jun 7, 2023 at 10:01
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    $\begingroup$ The equatorial bulge is about $21$ km (difference of radii). That's a hump of more than a few hundert meters. $\endgroup$
    – Kurt G.
    Commented Jun 7, 2023 at 10:25
  • $\begingroup$ there is a plot here mometrix.com/academy/earths-structure $\endgroup$
    – anna v
    Commented Jun 7, 2023 at 10:34
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    $\begingroup$ Keep in mind, that oceans changes together with Earth shape, so it's already part of bulge. Ocean displacement can only form in a sudden Earth angular velocity increase, otherwise if changes are slow (like it was in Earth protoplanet mass formation),- oceans as well as Earth shape changed very early in Earth evolution and then adapts slowly further to angular speed changes. $\endgroup$
    – Agnius Vasiliauskas
    Commented Jun 7, 2023 at 10:45
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    $\begingroup$ Related: physics.stackexchange.com/q/630859/226902 and physics.stackexchange.com/q/8074/226902 $\endgroup$
    – Quillo
    Commented Jun 7, 2023 at 16:49

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During the rotation of the Earth, a centrifugal force is formed, according to the actions of which ocean water should be collected at the Equator, forming a "hump" hundreds of meters high.

That is correct. The sea level at the equator is about $21\mathrm{\ km}$ further from the center of the earth than the sea level at the North Pole.

The depth of the ocean does not depend on latitude, although there should be such a dependence.

This doesn’t follow. The equatorial bulge of the land is also about $21\mathrm{\ km}$. So the depth of the ocean is approximately uniform.

The idea is that on geological scales rock is also somewhat like a fluid. You can only have a mountain a certain height before it “flows” down. So the same centrifugal force that makes water bulge also makes rock bulge.

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  • $\begingroup$ I don't believe that rock is actually a fluid over long time scales. Mountains don't flow down. They erode, and the sand grains and dirt they become are washed downhill. $\endgroup$
    – Peter Shor
    Commented Jun 7, 2023 at 15:29
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    $\begingroup$ @PeterShor On geologic timescales, I don't believe there's really any difference. Call it what you like. $\endgroup$
    – Logan J. Fisher
    Commented Jun 7, 2023 at 15:33

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