https://phys.org/news/2018-05-document-widespread-methane-seeps-oregon.html

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 total number of offshore seep emission sites to a whopping 1,000 locations.

It is not yet clear whether the methane presents an opportunity for a new source of energy or a potentially serious environmental threat, but for now the researchers want to map the distribution of the sites and conduct research on the composition and sources of the gas. They believe they will discover new methane seeps this summer when they utilize several research vessels to conduct additional mapping off the Northwest coast.