The IEA estimates that the output from mature fields outside OPEC would naturally drop by about 11% a year.

国际能源署估计非欧佩克成员国内的成熟油田产量每年将自然下降11%。

youdao

Same for Siberia, which has most of Russia's production, but from mature fields.

FORBES: Reserves

However, we believe that there are pockets of growth which the firm could leverage such as mature fields and global unconventional plays.

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This strategy, of ramping up investment in mature fields, is the same one he has applied through the other four big shelf acquisitions Exxi has made since its founding in 2005.

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