Ebullition of greenhouse methane (CH4) from the aquatic sediments is often observed at various hydrostatic pressure drops: at low tides, waves, and even at atmospheric pressure drops. It is especially pronounced at the different vent structures, for example, pockmarks, mud volcanoes, and cold seeps. The modeling conducted in the current study suggests that long timescale (glacial to centennial frequency) sea level drops may induce “stable” bubble ascent and control the position of the gas horizon in muddy aquatic sediment. Bubbles escape in the “dynamic” regime from the shallow gas horizon and subsequently to the water column is more feasible under shorter-period waves of higher amplitude travelling in shallow water. These findings are illustrated by examples of various vent structures (e.g., pockmarks), pronounced in shallow straits and bays, described in the literature.
Bibliographical noteFunding Information:
This project was supported by the Israel Science Foundation, grant 1441‐14. The data for this paper were obtained using the numerical modeling described in the paper. The author would like to thank the Editor and two anonymous reviewers for their substantial contributions in enhancing this paper. The author would also like to thank John K. Hall and Sharon Erez for editing this paper.
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- fracture mechanics
- muddy sediment
ASJC Scopus subject areas
- Earth and Planetary Sciences (all)