Peak phosphorus: look underwater?

Speaking of Peak Phosphorus, one of Tyler Cowen’s “Julian Simon savvy” commenters (who “descended from farmers”) is also not impressed.

Oh, and peak phosphate? Please. There are deposits on the contintental shelves sufficient for 1,000 years or more. Some are in quite shallow water. The Onslow Bay formation in North Carolina contains about 5x the current proven world reserves, all lying in water less than 20 feet deep.

I have heard about these types of underwater phosphate deposits but don’t know enough about them to verify their size, or how much it costs to extract them (or if anyone is actually extracting at commercial scale yet). Perhaps they will become the oil sands of phosphates: almost unlimited resources but at a fairly high position on the cost curve. In theory this would function as a long-term price ceiling on phosphates (although not short-term, as 2008’s oil price run-up showed us).