No caves or ores in world

Steps to Reproduce:
1. Build a shelter and start digging diagonaly down.
2. Dig vertically down.
3. Dig streight at the required altitude.
4. Start to strip mine at the required altitude.

Observed Results:
I haven’t been able to find any iron or cave or anything for that matter, not even coal.

Expected Results:
To find enough iron to make some basic tools and some coal to make torches, just like it used to be in old Minecraft.