On the latest snapshot their is a bug that at 3000000 ~ 3000000 the ocean floor is made out of stone and ores are exposed all the gravel and sand that should be their is gone.
MC-220062
Stone Ocean floor
Resolved
Duplicate
0
Thank you for your report!
We're tracking this issue in MC-214783, so this ticket is being resolved and linked as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
If you haven't already, you might like to make use of the search feature to see if the issue has already been mentioned.
Quick Links:
📓 Bug Tracker Guidelines – 💬 Community Support – 📧 Mojang Support
📓 Project Summary – ✍️ Feedback and Suggestions – 📖 Game Wiki