“…Gas hydrates are widely distributed in the marine sediments and permafrost and formed in low-temperature and highpressure conditions (Kvenvolden, 1993;Sloan & Koh, 2007). Extensive gas hydrate drilling sites show that gas hydrates have different morphologies and high saturation within the coarse-grained sand reservoirs, which show the high amplitude reflections and the same polarity as the seafloor reflections (Boswell et al, 2016;Collett et al, 2019;Cook & Malinverno, 2013;Cook & Waite, 2018;Fujii et al, 2015;Horozal et al, 2015;Portnov et al, 2019). Sand-rich reservoirs with high saturations are widely identified in the thin or thick channel-levee systems, such as the Gulf of Mexico (Meazell et al, 2020;Santra et al, 2020), the Krishna-Godavari Basin (Collett et al, 2019), the Nankai Trough (Fujii et al, 2009(Fujii et al, , 2015, the Hikurangi margin, New Zealand (Cook et al, 2020;Pecher et al, 2018;Pan et al, 2022) and the Ulleung Basin (Horozal et al, 2015).…”