The Earth derived the Plates from the Change in the rate of growth and expansion that occurred following the Major Impact that occurred at Wilkes Land Antarctica. The impact occurred at 252.17 Ma, but it took until 180 Ma for the Earth to heat up enough to grow and expand enough to fracture the surface and seperate into several different Continental Plates from what had previously been one contiguous continental surface (pangaea). The Impact in Antarctica was assuciated with an antipodal Energy focal point called the Siberian Traps. The antipodal rupture leaked enough lava to cover the entire surface of the Earth to a depth of 10 feet. The actual localized depth was about two miles of lava flows.
I suspect the Impactor was made of Uranium, and it detonated upon impact, the result was 28 large chunks of Uranium that scattered over the Earth, and burned their way down into the mantle, and down to the Earth's core. The result was 28 hot spots, One 480 km Impact Crater, the Siberian Traps, and a large amount of Uranium dust that ended up in layers in Basins worldwide. One of those Basins was at Crown Point NewMexico, and was going to be mined, until the price of Uranium fell from $45.00 to $ 16,00 , and it became uneconomical to mine deep deposits of Uranium.
Between Now and 180 Ma, the Radius of the Earth can be approximated by taking the Base = 0.996 558 283 and raise it to the " N " Ma, to get the 0.xxx xxx xxx Radius at the time period. For example: at 66.043 Ma, the radius was 0.996 558 283 ^ 66.043 = Radius = 0.796 368 413 R or 5074.8232 Km Radius. And
( 5074.8232 / 6372.4567 ) X 180 degrees = 143.346 3144 degrees. This is the
arc Distance up and over the top of the Earth between the Chicxulub Impact Site, and the Deccan Traps Antipodal Energy Focal Point. The 2 Delta = 180 - 143.346 3144 = 36.653 68555 degrees. The one Delta = 18.326 84278 degrees.
Chicxulub Impact site is now 20.4 degrees Noth of the Equator. At the time of Impact, It was 20.4 - 18.326 84278 = 2.073 16 degrees Noth of the Equator, and Western India which was 180 degrees away, was 2.073 16 degrees south of the Equator. Since Both Locations have moved North of the Equator, the conclusion is that the Earth grew in size (or expanded), and Most of the Continents have moved Northward with millions of Years of elapsed time, and they have moved apart, like the doors of a Delorean as they open upward. Only use 0.996 558 283^"N" Ma between 180.0 Ma, and Now to determine the Radius.