The parting of the Red Sea so that Moses could lead his people to safety is counted as an act of God, a miracle, but in fact occurred during the last cataclysms. The waters were separated partly due to the fact that there was sloshing of water and heaving of ground, but such a thing as the fact that the Red Sea could part, and that the whole troop could pass, and then come closed just as the enemy was about to follow in their footsteps, was not a natural occurrence. As you might imagine, things can be moved aside and artificial barriers such as force fields put in place. We are capable of putting a force field down that any weapon that humans possess could not penetrate, yet it is invisible. Without going into the technology of such a force field, this was simply put down, the water sucked out and put on the other side of the force field, allowing high walls of water on either side. Due to the intensity and fear, and excruciating knowledge of what they would receive at the hands of the Egyptians if they were recaptured, and the fervent following that Moses had, they all wandered into this in a leap of faith to a one, and crossed whole. The sea floor heaved up, temporarily, long enough to provide safe passage to Moses but not long enough for the Pharaoh's hapless soldiers, who followed.