4.75 billion years ago, a large star near what is now the Solar System went supernova, sending heavy element debris outward into the galaxy. Some of the debris, after traveling long distances through space, collided with a Hydrogen cloud.
I believe the answer is a deep oceanic trench. Hope this helped! <3
When tiny ice crystals in clouds stick together to form snowflakes, the result is snow. If enough crystals form a clump, they'll become heavy enough to fall to the ground. When temperatures are cold and moisture in the form of tiny ice crystals exists in the atmosphere, snow forms.
I believe flowing water would create erosion because tectonic plate movement and earthquakes are almost the same thing, and liquid rock is basically lava, and that only heats rock, rather than breaking it into smaller pieces, which is what flowing water does.