First crust is the outermost covering of our planet earth were we are standing and build lives with it. Past 250 million years ago, according to scientist their is only one supercontinent called pangaea and it was surrounded by the ocean named panthalassa. It's because of the movements of tectonic plates underneath it was cracked and separated causing we have 7 continents nowadays. Crust maybe different but connected on the theory i have mention. It will maybe submerged in how many million years to come. As mother nature take revenge on us it was a horrible thing if something happens again causing maybe the oceans and seas to be shallow and submerged into oceans, lands may spread out and plants can't hold unto these. Maybe it may change the soil because of submissive explosion of lava coming from the volcanic eruption.