People keep forgetting that THIS is what Earth looked like in Pre-Cambrian Times. Also, large craters are STILL being made!
Compressed soil beneath the impact lithified easier than rocks which were not compressed. Rocks that were metamorphosed or melted are even more likely to survive. "Regolith" should be found in these ancient rocks just as they are on the moon, except the presence of oxygen and water would "rust" any metals in the impact debris, converting them from primary minerals to secondary minerals.. ANY ancient layers found should be covered with the unusual differentiated minerals placed by impacts. Craters in lowlands tend to fill with evaporates from the waters that fell or seeped in to them, covering the area with salts. Large craters made firm foundations for large stable features like the Colorado Plateau.
The center of the earth is filled with radioactive heavy minerals that break down and provide the heat that keeps the iron core at around 6,000 degrees C. Did a LARGE impactor crack the earth's outer layer like an eggshell and initiate Continental Drift?