Split-beam (EK60) sonar image of bubbles

Split-beam (EK60) sonar image of bubbles (green) in the water column at a seep site overlooking Baltimore Canyon on the U.S. Atlantic margin. Although the bubbles appear to nearly reach the sea surface, the methane contained in the bubbles would have dissolved and been replaced by other gases by the time the bubbles rise several hundred meters. Since 2012, images such as these have led to the discovery of hundreds of methane seeps on the U.S. Atlantic margin in an area previously thought to be devoid of such leakage