Really, it is difficult to reply to this question in a few sentences.

Please see, for instance, our chapter presented in the ResearchGate:

Pilchin, A.N. and Eppelbaum, L.V., 2012. The Early Earth, Formation and Evolution of the Lithosphere in the Hadean – Middle Archean, In: (Eds. Sato, F. and Nakamura, S.) Encyclopedia of Earth Science Research (3 Volume Set), Ser.: Earth Sciences in the 21st Century, Nova Science Publishers, N.Y., USA, 1-93.

The crust of the Moon is 60 km on the near side and 80 km on the far

side. Since the Earth is older than the Moon, the Earth's crust should be

thicker than the Moon's Crust, but it is thinner at an average of around

39.8 km thick.

The world's most unloved theories is Growth and Expansion of Planets,

but the crustal thickness " deficiency " problem may be due to

a redistribution of materials out from under the Earth's Continental

crust to feed the newly forming Oceanic crust.

The Oceanic Crust is between 5 and 7 km thick, and is only between

zero and 252 million years old.

The continental Crust is 4544.40 million years old and is

thinned from a prior greater thickness to about 39.8 km thick.

252 million years ago, the continental crust of Pangaea was

around ( 1/0.2904 ) x 39.8 = 135.7 km thick.

At T = zero, the crust was 0 km thick and the Planets radius

was about 1703.4 KM.

At T= 4300 MY, the Radius was 3434 km and the Thickness

was 135.7 km thick.

At T = 4544.4 MY, the Radius is 6372.4567 Km and the

Thickness due to material redistribution is reduced to

39.8 km thick.

The Planet follows an exponential growth curve which

was very slow until 252 million years ago, but has accelerated

since then.

You should be able to get crustal thickness info from Mars and

possibly from venus.

Now it is computer time.

I have never been able to figgure it out since the Earth has

an external source of growth, and an Internal source of growth.

The Hazen-Tharp Map should help, or

get a copy of Terra Non-Firma Earth from

James Maxlow _ Perth Australia.

Have Fun.