And what they have found is eye-opening. Since the first evidence of underwater methane was discovered in the late 1980s, only about 100 “seep sites” had been identified along the Northwest coast through 2015. They often were discovered by accident, when fishermen would spot anomalies on their fish-finders that turned out to be acoustic reflections of the bubbling methane gas.
But over the past two years the scientists — aided by new sonar technology on the Exploration Vessel (E/V) Nautilus, owned and operated by the Ocean Exploration Trust — have purposefully gone seeking evidence of underwater methane and have expanded the
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