APPLICATION OF ENVISAT SAR IMAGERY FOR MAPPING AND ESTIMATION OF NATURAL OIL SEEPS IN THE SOUTH CASPIAN SEA

摘要

Numerous oil slicks of natural origin were revealed in the southwest part (SW) of Caspian Sea on the synthetic aperture radar (SAR) images acquired by the Envisat satellite in 2003-2004. Analysis of the SAR images together with bathymetry, geophysical and seismic data in geographic information system showed that the main hydrocarbon contribution visible on the sea surface as oil slicks comes from the natural seepage. Oil slicks are basically concentrated over the local geological formations of the sedimentary cover having oil and gas resources. In total about 90 seeps distributed across the SW Caspian Sea having repeating regime and an active type were identified. Seepage rate of oil in the SW Caspian Sea is estimated to be up to 16,000 metric tons per year. Conclusion is done that the SAR onboard the Envisat satellite is an excellent tool for studying oil seeps through observation oil slicks floating on the sea surface.