Processing of parametric array sub-bottom profiles and the application in identifying shallow gas hydrates

Parametric array sub-bottom profile detection technology has been rapidly developed recently into an effective method for shallow gas hydrate detection due to its simple acquisition mode and high-resolution shallow strata imaging capability. To better obtain geological information on the shallow gas hydrate in the East China Sea, we performed a detailed processing of the parameter array sub-bottom profile. First, the methods of abnormal amplitude suppression and spatial amplitude equalization were combined to solve the problems of noise and energy imbalance. Then, the Hilbert transform was used to improve the stratigraphic resolution. Finally, signal enhancement technology was used to improve the continuity of the events and the resolution of wave group characteristics. The processed parameter array sub-bottom profile features high signal-to-noise ratio, good continuity, and clear stratigraphic structure, which can better reveal seismic reflection characteristics such as blank zones, gas chimneys, bright spots, and anomalies like flame, which lays the foundation for identifying shallow gas hydrate. Furthermore, seismic attributes (curvature attribute, instantaneous amplitude attribute, coherence attribute) were analyzed and result show that acoustic anomalies related to shallow gas hydrate leakage could be clearly identified. The study not only verified the feasibility of the parametric array sub-bottom profile processing method for shallow gas hydrate, but also explored the application of attribute analysis technology in the identification of shallow gas hydrate.