Univ. of Texas, Austin, TX (United States). Jackson School of Geosciences. Inst. for Geophysics; Univ. of Texas, Austin, TX (United States)
Univ. of Texas, Austin, TX (United States). Jackson School of Geosciences. Inst. for Geophysics; Univ. of Texas, Austin, TX (United States). Jackson School of Geosciences. Dept. of Geological Sciences
We explored methane hydrate formation with sedimentation with a newly developed one-dimensional, multiphase flow, multicomponent transport numerical model. Our model couples methane hydrate formation from in situ microbial methane generation within the hydrate stability zone (HSZ), methane recycling, and microbial methane generation below the base of the hydrate stability zone (BHSZ). Both recycled methane and deeply generated methane are transported into the HSZ by buoyancy-driven free gas flow. Free gas flows through the HSZ by both the processes of capillary-dependent pore fillings and by salt exclusion during hydrate formation, with the former being the dominant mechanism. We quantitively illustrated the formation of enriched hydrate in muddy sediments above, and interconnected free gas below, the BHSZ, which are common features along the world's continental margin. In addition, we showed two ways to form concentrated methane hydrate above the BHSZ. The first mechanism is local free gas flow during methane recycling. This happens at sites with sufficient methane generation above the BHSZ. The second mechanism is deep microbial methane generation which is transported into the HSZ by free gas flow. This mechanism plays a more important role at sites with high sedimentation rates. This study provides new insights into methane hydrate formation and distribution below the seafloor. It is important for understanding the carbon cycle and carbon storage below the seafloor and for resource evaluation and exploitation.
You, K. and Flemings, P. B.. "Methane Hydrate Formation and Evolution During Sedimentation." Journal of Geophysical Research. Solid Earth, vol. 126, no. 4, Mar. 2021. https://doi.org/10.1029/2020jb021235
You, K., & Flemings, P. B. (2021). Methane Hydrate Formation and Evolution During Sedimentation. Journal of Geophysical Research. Solid Earth, 126(4). https://doi.org/10.1029/2020jb021235
You, K., and Flemings, P. B., "Methane Hydrate Formation and Evolution During Sedimentation," Journal of Geophysical Research. Solid Earth 126, no. 4 (2021), https://doi.org/10.1029/2020jb021235
@article{osti_1849116,
author = {You, K. and Flemings, P. B.},
title = {Methane Hydrate Formation and Evolution During Sedimentation},
annote = {We explored methane hydrate formation with sedimentation with a newly developed one-dimensional, multiphase flow, multicomponent transport numerical model. Our model couples methane hydrate formation from in situ microbial methane generation within the hydrate stability zone (HSZ), methane recycling, and microbial methane generation below the base of the hydrate stability zone (BHSZ). Both recycled methane and deeply generated methane are transported into the HSZ by buoyancy-driven free gas flow. Free gas flows through the HSZ by both the processes of capillary-dependent pore fillings and by salt exclusion during hydrate formation, with the former being the dominant mechanism. We quantitively illustrated the formation of enriched hydrate in muddy sediments above, and interconnected free gas below, the BHSZ, which are common features along the world's continental margin. In addition, we showed two ways to form concentrated methane hydrate above the BHSZ. The first mechanism is local free gas flow during methane recycling. This happens at sites with sufficient methane generation above the BHSZ. The second mechanism is deep microbial methane generation which is transported into the HSZ by free gas flow. This mechanism plays a more important role at sites with high sedimentation rates. This study provides new insights into methane hydrate formation and distribution below the seafloor. It is important for understanding the carbon cycle and carbon storage below the seafloor and for resource evaluation and exploitation.},
doi = {10.1029/2020jb021235},
url = {https://www.osti.gov/biblio/1849116},
journal = {Journal of Geophysical Research. Solid Earth},
issn = {ISSN 2169-9313},
number = {4},
volume = {126},
place = {United States},
publisher = {American Geophysical Union},
year = {2021},
month = {03}}