This is a bit of an addendum to a previous question, shown here. (How to Cause a Hydrosphere Apocalypse Part II The Great Flood). I like the rain of ice from a dying moon, answer and I have decided to use the world in part two as a springboard for a setting in a novel.
But I have run into a tad bit of a snag.
The wiki for the film Waterworld, (a major bit of inspiration) says that the global flood added 25,000 ft to the global sea level. Now, this presents a couple problem for the story I wish to tell.
See the locals are air breathers capable of holding their breath for 30 minutes. I want them to be able to reach the sea bed, (at least for the shallower parts) and scavenge for parts and one set piece I really wanted to use is the ruins of a flooded city with the tops of sky scrapers poking out of the waves, inspired by this image by Slava Vidyapin.
Now the shallowest sea bed being 4.7 miles down presents an understandable problem to all those requirements.
But then it hit me. Erosion.
The flood that will swallow this particular world isn’t coming up from a rising sea, it’s coming from above in a rain of ice and water. And not just for 40 days and nights but for centuries even millennia. And usually such rains can wash away the land and thus maybe make the resulting sea that much shallower. But I wanted the opinions of those who know better than I.
So, Would a thousand years of rain and icy meteors lead to enough erosion to ensure a shallow sea water world?