Global Seeps screening uses satellite data acquired over the ocean to detect any oil slicks that may be present on the sea surface. The imagery is interpreted to identify slicks which may be sourced from natural seepage from hydrocarbon reserves.
When oil leaks from a reservoir under the sea floor, small oil coated gas bubbles travel up through the water column to the sea surface, where they form a very thin film on the water. This film can then be detected on satellite imagery and mapped, providing the data is collected under the correct weather and ocean conditions.
To ensure the quality of the Global Seeps results, all imagery used is extensively screened for weather compliancy and a minimum of two dates of imagery per scene footprint is acquired for all offshore areas. Using at least two image dates helps to increase the confidence of each feature found as well as pinpoint source points for multi-date seeps.