90%

I read the other day that the current surface of the earth is 90% sedimentary rock. That means that 100% of the current earth's surface has been under water for extended periods of time.  The most intriguing aspect to that fact is where did the sediment come from?  What was above the surface of the water that could erode and flow into the water to become sediment? What portion of the globe was above and what portion below? Apparently there is some evidence that Africa and South America share some geologic features. That has led to the notion of plate tectonics. In my thinking they must have been under the water at the same time.

Even the Himalayas are sedimentary in composition. What is the mechanism that erodes the above water surface onto the below water surface than pushes the below water surface above the surface and then erodes that? I don't believe tectonics is a credible description because there is no explainable force which causes the plates to sub-duct or the plates to crash into one another.  Unless heat is applied sugar water doesn't boil and if it is not stirred the top surface crystallizes. It is the escaping of the water which causes the contents to  fall in onto itself.

So in the case of the earth did it start out as a rock covered by water or a liquid concoction that separated into layers like a bottle of muddy water.  Assuming that it was a concoction that would account for the layering of the earth as the elements responded to the force called gravity.  As the heavier elements aggregated at the core of the globe eventually igniting and adding a second mechanism called heat caused the water to evaporate and then condense on a rapidly cooling surface.  As the globe continued to shrink the surface began to buckle and create nonconformity.  The motion of the planet adds a third mechanism which is stress which shows up as fault lines.  As the planet cools and its interior contents escape to the exterior the earth is transformed.