Polarimetric　Synthetic　Aperture　Radar　(SAR)　has　powerful　capability　in　marine　oil　spill　detection　since　it　could　distinguish　clean　sea　surface　from　mineral　oil　spill　and　false　alarms　as　biogenic　thin　films.　As　an　alternative　to　fully　polarimetric　(FP)　SARs,　which　provide　complete　scattering　information,　compact　polarimetric　(CP)　SARs　transmit　a　polarized　signal　different　from　conventional　horizontal　and　vertical　ones,　while　receiving　coherently　the　backscattered　signal.　Hence,　they　could　obtain　partial　polarimetric　information　while　maintaining　a　large　swath-width,　which　makes　it　an　ideal　tool　for　marine　oil　spills　observation.　However,　the　proper　selection　of　compact　polarimetric　SAR　modes　still　remains　a　critical　issue.　By　transmitting　SAR　signal　with　different　polarizations,　the　scattering　mechanism　of　the　sea　surface　can　be　reflected　by　different　CP　SAR　features.　Hence,　it　is　necessary　to　analyze　the　behavior　of　sea　surface　scattering　as　experienced　by　different　CP　SAR　modes,　i.　e.,　different　transmitted　polarization.　In　this　paper,　a　unified　framework　was　applied　to　derive　compact　polarimetric　SAR　features　under　General　Transmit　and　Linear　Receive　(GTLR)　polarization　configurations.　Following　the　rationale　of　polarization　signature,　the　characteristics　of　features　derived　by　transmitting　signals　under　different　roll　and　ellipticity　angles　are　analyzed.　Experiments　were　conducted　on　a　UAVSAR　(Uninhabited　Aerial　Vehicle　SAR)　FP　SAR　image　acquired　at　L-band　during　an　oil-on-water　exercise　conducted　offshore　the　Norwegian　coast,　where　plant,　crude　oil,　and　oil　emulsions　with　different　oil-water　mixtures　were　released　at　sea.　©　2019　IEEE.