The proved reserves in Cenozoic, Mesozoic, Upper Palaeozoic, Lower Palaeozoic, Proterozoic respectively are 38%, 17%, 30%, 13% and 2% in total.

• 新生界、中生界、上古生界、下古生界和元古界分别占总探明地质储量的 38%25、17%25、30%25、13%25和 2%25。