Submarine Slides and Their Influence on Gas Hydrate and Shallow Gas in the Pearl River Mouth Basin

Submarine slides, gas hydrates, shallow gas, and volcanoes considered to be potential geohazards have been well delineated using three-dimensional (3D) seismic data and well log data in the Pearl River Mouth Basin, South China Sea. Seismic characteristics, distribution maps, and controlling factors of these geohazards have been well analyzed showing the influence of regional tectonics and sedimentary processes. Recently, shallow gas and gas hydrates are confirmed by drilling expeditions, which are considered important unconventional resources. Moreover, the mapped features of various geohazards show the spatial overlays and that they are connected each other. To delineate well the relationships between gas hydrates, shallow gas, and the potential geological features such as submarine slides, gas chimneys, faults, and volcanoes, the seismic attributes and interpretations are displayed using 3D seismic data to show the interplay between them. Gas hydrates and shallow gas occur and are widely distributed above sills, volcanoes, gas chimneys, and faults within the submarine slides and migrating canyon because large amount of hydrocarbon gas can migrate from the deep layer to the shallow layer along different pathways. This study aims to show the correlation among various geological bodies and their effects on shallow gas and gas hydrate distributions.