@article{oai:kanazawa-u.repo.nii.ac.jp:00060887,
 author = {Majima, Ryuichi and Ochi, Mayumi and Miura, Misa and Hitomi, Makiko and Saito, Takeshi and Namiki, Yuuki and Ohtsuka, Yusuke and Shimizu, Hidetomo and Nozaki, Atsushi and Utsunomiya, Masayuki and Kusu, Chie and Sato, Kei and Kawagata, Shungo and Wani, Ryoji and Nakamura, Eiko and Sakai, Saburo and Wada, Hideki and Kitazato, Hiroshi and 間嶋, 隆一 and 越智, 眞弓 and 三浦, 美佐 and 人見, 真紀子 and 齋藤, 猛 and 並木, 勇樹 and 大塚, 悠佑 and 清水, 秀倫 and 野崎, 篤 and 宇都宮, 正志 and 楠, 稚枝 and 佐藤, 圭 and 河潟, 俊吾 and 和仁, 良二 and 中村, 栄子 and 坂井, 三郎 and 和田, 秀樹 and 北里, 洋},
 issue = {9},
 journal = {地質学雑誌, The Journal of the Geological Society of Japan},
 month = {Sep},
 note = {冷湧水性群集が房総半島の中部更新統柿ノ木台層の陸棚相から産出する．群集は，化学合成二枚貝類から排他的になり，著しく13Cに枯渇した自生炭酸塩と共産することから，AOM（嫌気的メタン酸化）に依存していたと考えられる．自生炭酸塩は巣穴壁面と巣穴周囲の堆積物中に沈殿し，巣穴からスナモグリ類の爪化石と糞化石が産出することから，これらはスナモグリ類の巣穴であると考えられる．スナモグリ類はメタン生成帯まで巣穴を堀り，海水を巣穴深部へ供給し，AOMを活性化させることによって巣穴中の硫化水素イオン濃度を上昇させた．溶存酸素濃度が高い巣穴浅部では，硫黄酸化菌が繁茂し，スナモグリ類の食糧となった．巣穴深部では，浮遊する生物源炭酸塩などを核とした針状アラゴナイトが重力方向に沈下して炭酸塩ジオペタル状構造を形成し，巣穴周囲の堆積物中では，リン酸イオン濃度の上昇により高Mgカルサイトが，また硫酸イオンの枯渇によりドロマイトが沈殿した．, Cold-seep-dependent molluscan assemblages occur in the outer-shelf facies of the middle Pleistocene Kakinokidai Formation of the Kazusa Group, a forearc basin-fill sequence on the Pacific side of central Japan, in strata corresponding to the interval 707.6-667.0 ka. The assemblages consist exclusively of chemosymbiotic bivalves (lucinids, thyasirids, and solemyids) and are associated with 13C-depleted authigenic carbonates (δ13C = −61.60‰ to −10.96‰ VPDB), which suggest that their main carbon source was anaerobic oxidation of methane (AOM). Authigenic carbonate precipitates are common on burrow walls (mainly acicular aragonite) and the surrounding sediments (mainly micritic high-Mg calcite and dolomite). The burrows are cylindrical, 1.5-3.0 cm in diameter, and >1 m long. Callianassid claws and the trace fossil Palaxius (probable callianassid fecal pellets) in the burrow carbonates suggest that the burrows were produced by sediment-dwelling callianassid decapods.
\nWe propose the following formation mechanism of burrows and their related authigenic carbonates. Firstly, callianassids produced deep burrows, penetrating the AOM zone and reaching the methanogenic zone. Methane then seeped into the burrows and AOM occurred in its deeper parts, promoted by a supply of seawater via callianassid activity, resulting in an increase in the concentration of hydrogen sulfide ions. Thiobacteria flourished in the shallower parts of the burrows, which were enriched in dissolved oxygen, and provided a source of food for the callianassids. In the deeper parts of the burrows, acicular aragonite precipitated around suspended carbonate nuclei and sank to the bottoms of the burrows, forming geopetal-like carbonate structures. In the surrounding sediment, high-Mg calcite precipitated in response to an increase in the concentration of phosphate ions (due to the decomposition of organic matter), and dolomite precipitated in response to decreasing concentrations of sulfate ions (caused by active AOM)., 金沢大学国際基幹教育院 GS教育系},
 pages = {655--683},
 title = {千葉県君津市川谷地域に露出する中部更新統柿ノ木台層から産出する冷湧水化石群集: その時空分布と共産する自生炭酸塩},
 volume = {125},
 year = {2019}
}