The tidal influence on oil and gas emissions from an abandoned oil well: Nearshore Summerland, California

Oil and gas emissions were quantified for natural and human sources in nearshore waters off Summerland, California through deployment of custom designed collection tents. Seepage was measured at a repeatedly abandoned well, on the seabed from a caisson located along the historical location of the Treadwell Wharf, where the world’s first off-shore oil wells were drilled at the end of the 19th century. Seepage rates at the capped T-10 Well, located in ∼5 m water, showed high correlation to tides. Site emissions were 2.4 and 38.7 L day−1 oil and gas, respectively. Emissions were measured from two areas of seepage at the T-10 Well Site. Oil and gas ratios were inversely correlated between the two seepage areas, demonstrating connectivity. Data were interpreted in terms of an electronic circuit model of seepage with respect to the time lag between local low tide and peak oil emissions.