Characteristics of submarine hydrate pingos and mud volcanoes and their effects on gas hydrate accumulation

Submarine hydrate pingos and mud volcanos are both the products of upward migration and discharge of fluids in different phases to the surface. The shallow gas hydrate reservoirs related to these two special geological bodies have unique formation process and occurrence, and at the same time, they are also an important way of carbon-rich fluid emission. However, due to the lack of systematic investigation and research about these two geological bodies, and the lack of attention to shallow gas hydrate resources and carbon leakage, there are still obstacles in fine characterization and accurate discrimination of submarine hydrate pingos and mud volcanoes. This makes it difficult to scientifically evaluate the accumulation process and environmental effects of their associated gas hydrate resources. In this study, by summarizing the existing researches on the submarine hydrate pingos and mud volcanos, the two special geological bodies are compared from the aspects of geomorphic characteristics, internal structure and formation mechanism. The evolution the process of the two geological bodies and their influence on the related gas hydrate accumulation process are systematically analyzed, and the essential differences and relations between the two geological bodies are discussed. We hope this study might provide an important reference for the research on submarine carbon leakage and its contribution to the carbon cycle, as well as the evaluation of global shallow gas hydrate resources.