“…A number of studies have suggested that the occurrence of this methane seepage is related to subsurface gas hydrate (Li et al, 2013;Zhang et al, 2014a;Sha et al, 2015). Previous studies demonstrated that the tectonic and sedimentary conditions in the Dongsha region are beneficial for the formation and accumulation of gas hydrate (Song et al, 2000;McDonnell et al, 2000;Wu et al, 2004;Yan et al, 2006;Wang et al, 2006;Lin et al, 2009;Schnürle et al, 2011;Li et al, 2012aLi et al, , 2013. For instance, McDonnell et al (2000) indicated that marine sediments in the Dongsha region located in passive continental margin have appropriate-thickness, methane-generating potential to host gas hydrate.…”