1. Evidence in the Japan Sea of microdolomite mineralization within gas hydrate microbiomes.
- Author
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Snyder GT, Matsumoto R, Suzuki Y, Kouduka M, Kakizaki Y, Zhang N, Tomaru H, Sano Y, Takahata N, Tanaka K, Bowden SA, and Imajo T
- Subjects
- Aquatic Organisms chemistry, Bacteroidetes chemistry, Biodegradation, Environmental, Fossils, Geologic Sediments chemistry, Microbiota, Petroleum metabolism, Seawater chemistry, Seawater microbiology, Aquatic Organisms metabolism, Bacteroidetes metabolism, Calcium Carbonate chemistry, Geologic Sediments microbiology, Magnesium chemistry, Methane metabolism
- Abstract
Over the past 15 years, massive gas hydrate deposits have been studied extensively in Joetsu Basin, Japan Sea, where they are associated primarily with active gas chimney structures. Our research documents the discovery of spheroidal microdolomite aggregates found in association with other impurities inside of these massive gas hydrates. The microdolomites are often conjoined and show dark internal cores occasionally hosting saline fluid inclusions. Bacteroidetes sp. are concentrated on the inner rims of microdolomite grains, where they degrade complex petroleum-macromolecules present as an impurity within yellow methane hydrate. These oils show increasing biodegradation with depth which is consistent with the microbial activity of Bacteroidetes. Further investigation of these microdolomites and their contents can potentially yield insight into the dynamics and microbial ecology of other hydrate localities. If microdolomites are indeed found to be ubiquitous in both present and fossil hydrate settings, the materials preserved within may provide valuable insights into an unusual microhabitat which could have once fostered ancient life.
- Published
- 2020
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