A specialized unit called a jackup rig, at left, drilled a natural gas well last year at Hilcorp’s Tyonek platform, right, in Cook Inlet. (Nathaniel Herz for Alaska Public Media) There are 17 offshore ...

The Spurr oil platform stopped pumping crude from beneath the silty ocean water outside Anchorage in 1992. The platform, built in Cook Inlet during Alaska’s first oil boom in the 1960s, was losing ...

Hilcorp’s Spurr platform, photographed last year, has not produced any oil or gas since 1992. (Nathaniel Herz for Alaska Public Media) The Spurr oil platform stopped pumping crude from beneath the ...

The platform, built in Cook Inlet during Alaska’s first oil boom in the 1960s, was losing money, officials from owner Marathon Oil wrote in a letter to the state. Oil production was expected to ...