“…Numerous gas seeps are associated with tectonic linear cracks, which manifest themselves in bottom sediments in the form of elongated linear anomalous zones for methane, its homologs, helium, hydrogen, and sometimes CO 2 [24,25]. Such anomalous zones have been found in many marine basins: for example, in a linear fault extending along the center of the Tatar Strait in the Japan Sea [26][27][28][29]. In our study, the concept of a gas anomaly is considered to be a concentration exceeding the background values by more than two times [1].…”