You are correct. In fact, they never will be depleted. Same with the oil. Most of the oil that is still in the ground will stay there.
"These forecasts are made possible by assuming the limit on the amount of oil extracted is the amount of oil in the ground. In fact, the limit is likely to be a financial (debt) limit that comes much sooner."
Please also see:
Extracted: How the Quest for Mineral Wealth Is Plundering the Planet
It is well possible we are beyond the peak already. This brings us to the "Seneca effect"
Otherwise: Business as usual.
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