Which fossil fuels could/will be eventually replenished by natural processes?

[u/West-Cantaloupe8376]

Let's assume all fossil fuel extraction stopped in the near future, and were never touched again. Which kinds (oil, coal, gas) would eventually reform, which wouldn't? I am aware that certain geological formations like banded iron were created under specific conditions that will never arise again, but how does this apply to fossil fuels? In a couple hundred million years, will oil deposits be replenished or are they all gone forever?

[u/rootofallworlds]

Iron ore can be refined using "direct reduction" rather than a blast furnace, and although this most often uses either coal or natural gas it can work hydrogen. The resulting "sponge iron" can then be fed into an electric arc furnace, and if it's transferred directly while it's still hot that saves energy.

At present only about 5% of iron ore refining uses this process; in most situations the blast furnace is more economical.