forbes:

While Russia and Iran have their own ocean access, the Caspian remains a prize for them as well because of its vast hydrocarbon reserves. The EIA predicts that the region’s natural gas supplies could add as much as 27% to global production over the next 10 years. That is, if they can be accessed. Much of the Caspian’s oil and gas lies in the South Caspian Basin, which spans Azerbaijan, Iran and Turkmenistan, where territorial disputes have hindered offshore exploration.

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