Significance and role of chemosynthetic bacteria in the formation of Carboniferous, deep-water, laminated carbonates.

化学合成细菌在石炭系深水层状碳酸盐形成中的意义和作用。

• 批准号: 01540625
• 负责人: MATSUMOTO Ryo
• 金额: $ 1.02万
• 依托单位: University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1989
• 资助国家: 日本
• 起止时间: 1989 至 1990
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-01540625/
• 关键词: deep-water carbonates; oxygen isotope composition; tube worm; chemosynthetic bacteria; cold vent; 酸素・炭素同位体組成; チュ-ブウォ-ム; 冷水湧水; 熱水噴出

1. Thin section analyses and close inspection of hand specimens, which were collected during the field survey in 1991, have revealed that 1) carbonatemounds characterized by chemosynthetic communities distributed not only in New Foundland, but also in New Brunswick, and 2) methane-seepage from the sea floor prevailed in very wide sedimentary basin in the Atlantic Canada during Carboniferous age.2. Carbon and oxygen isotope compositions were determined on calcite from tube worm mounds. Skeletal calcite of bryozoa and brachiopod have 1.1 to -1.4 o/oo delta^<13>C (PDB) and -3.6 to -6.6 o/oo delta^<18>O (PDB), whereas sparry calcite cement filling interstices of shells and cavities have 2.3 to -1.9 o/oo delta^<13>C and -8.6 to -10.7 o/oo delta^<18>O. Light oxygen of sparry calcite may suggest higher temperature of precipitation.3. Sulfide minerals occur as various forms in tube worm mounds. Disseminated pyrite has delta^<34>S of 0.75 to 6.37 o/oo, whereas massive sulfide ore a few m in diameter has delta^<34>S of 28.3 o/oo. This suggests that massive sulfide ore was precipitated from the more evolved "sea-water" at higher temperatures compared with disseminated pyrite.4. Combined textural analyses, chemical analyses, and isotopic signatures lead us to conclude that tube worm mounds were formed in the following processes : 1) Microbial process controlled by enhanced seep and expulsion of cold, methane and sulfide containing solutions, 2) development of calcite cement due to increased temperatures and mixing of connate waters, and 3) formation of massive sulfide ores caused by migration of high-temperature brines derived from deeper levels.

1.对1991年野外调查期间采集的手部标本进行了薄片分析和仔细观察，发现1)以化学合成群落为特征的碳酸盐沉积带不仅分布在新福克兰，而且在新不伦瑞克也分布在那里；2)在石炭纪时期，来自海底的甲烷渗漏盛行于加拿大大西洋非常宽广的沉积盆地中。测定了管虫土丘中方解石的碳、氧同位素组成。苔藓虫和腕足类骨骼方解石组成为1.1~-1.4 o/oo Delta^&lt；13&gt；C(PDB)和-3.6~-6.6 o/oo Delta^&lt；18&gt；O(PDB)，而闪光方解石胶结物充填贝壳和洞穴间隙具有2.3~-1.9 o/oo Delta^&lt；13&gt；C和-8.6~-10.7 o/oo Delta^&lt；18&gt；O。亮晶方解石具有较高的沉淀温度。硫化物矿物以各种形式出现在管虫土堆中。浸染型黄铁矿的S三角洲为0.75~6.37o/oo，而直径几米的块状硫化矿石的S三角洲为28.3o/oo。这表明与浸染型黄铁矿相比，块状硫化物矿石是在更高的温度下从演化程度更高的海水中沉淀出来的。结合结构分析、化学分析和同位素特征，我们得出结论：管虫丘的形成经历了以下过程：1)受冷、甲烷和硫化物溶液的增强渗漏和排出控制的微生物过程；2)由于温度升高和伴生水的混合而形成的方解石胶结物；以及3)来自深部的高温卤水的迁移导致块状硫化物矿石的形成。

项目成果

P.E.Schenk,R.Matsumoto and P.Bitter: "Deepーwater carbonate and turbidite sedimentation within Early Carboniferous (Visean) redbeds and evaporite,Atlantic Provinces,Canada." American Journal of Science. (1989)

P.E.Schenk、R.Matsumoto 和 P.Bitter：“早石炭世 (Visean) 红层和蒸发岩中的深水碳酸盐和浊积岩沉积，加拿大大西洋省份 (1989)。”

Ryo Matsumoto: "Vuggy carbonate crust formed by hydrocarbon seepage on the continental shelf off Baffin Island, northeast Canada" Geochemical Journal. 24. 143-158 (1990)

Ryo Matsumoto：“加拿大东北部巴芬岛附近大陆架上碳氢化合物渗漏形成的孔洞碳酸盐结壳”《地球化学杂志》。

Ryo Matsumoto: "Isotopically heavy oxygenーcontaining siderite derived from the decomposition of methane hydrate." Geology. 17. 707-710 (1989)

Ryo Matsumoto：“来自甲烷水合物分解的同位素重含氧菱铁矿。地质学”17. 707-710 (1989)

Ryo Matsumoto: "Vuggy Carbonate crust formed by hydrocarbon on the continental shelf off Baffin Island,northeast Canada." Geochemical Journal. 24. 143-158 (1990)

Ryo Matsumoto：“加拿大东北部巴芬岛附近大陆架上的碳氢化合物形成的凹凸不平的碳酸盐地壳。”

Ryo Matsumoto: "Isotopic evidence for the hypoー and hypersaline dolomitization of deepーwater carbonates,Atlantic Provinces,Canada." Canadian Journal of Sciences.

Ryo Matsumoto：“深水碳酸盐的低盐和高盐白云石化的同位素证据，加拿大大西洋省份。”