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Abstract Fossil worm tubes were collected from the Hayama Group, Miura Peninsula, Japan, together with abundant fossils of Calyptogena-Acharax clams. The fossil worm tubes were well preserved and coated with milky white amorphous silica. Most of the tubes were 1-3 mm in diameter, and up to 10 cm in length. Worm tubes were found in siltstone and limestone, and formed network-like assemblages. Elemental mapping on the tube cross-sections revealed the localization of sulfur, zinc and iron at the worm tubes, which suggests that sulfur-related metabolism and deposition occurred in association with the worm tubes. High resolution analysis revealed the localization of zinc-sulfur (sphalerite, ZnS) on the tubes, while iron-sulfur (pyrite, FeS2 ) was localized at the center of the tubes. The spatially separate sphaleritization and pyritization imply that epiphytic and endosymbiotic microorganisms perform different sulfur metabolisms, such as sulfate-reduction and sulfide-oxidation. 相似文献
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冷泉渗漏区海底微生物作用及生物标志化合物 总被引：8，自引：0，他引：8
在有冷泉活动和水合物产出的海底环境中,甲烷氧化古细菌和硫酸盐还原细菌十分发育,它们主导着海底天然气(主要是甲烷)的缺氧氧化作用,并在海底碳循环和生物种群繁衍中发挥着重要作用。海底天然气渗漏活动区的甲烷氧化古细菌使渗漏CH4缺氧氧化为HCO3-,硫酸盐还原细菌使SO42-转化为HS-,从而使细菌微生物获得生命所需的能量,生物种群得以发育和繁衍。甲烷氧化古细菌有ANME-1、ANME-2、ANME-3三个种群,形成相应的醚类异戊二烯类和类异戊二烯烃类生物标志物。硫酸盐还原细菌有Desulfosarcina和Desulfococcus两个主要的细菌群落,形成二烃基甘油二醚和脂肪酸生物标志化合物。这种天然气渗漏区内微生物活动产生的生物标志化合物都具有特别负的碳同位素组成,δ13C值为-41.1‰~-95.6‰,说明微生物群落在生命代谢过程中摄取了来自甲烷的碳,同时也反映了天然气渗漏系统缺氧带存在的古细菌和硫酸盐还原细菌活动。 相似文献
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南海北部冷泉碳酸盐岩具有包裹结构和孔洞结构,并且含有丰富的生物遗迹。利用电子探针对位于不同结构单元(包裹结构和基质)的自生碳酸盐矿物和钙质生物壳体进行了Mg/Ca和Sr/Ca分析,结果显示:自生碳酸盐矿物Mg/Ca变化范围为0.50~39.19mmol/mol,平均为12.50mmol/mol,Sr/Ca变化范围为0.06~2.90mmol/mol,平均为0.53mmol/mol;钙质生物壳体Mg/Ca变化范围为1.14~84.57mmol/mol,平均为24.57mmol/mol,Sr/Ca变化范围为0.77~1.84mmol/mol,平均为1.08mmol/mol。Mg/Ca和Sr/Ca的关系显示自生碳酸盐矿物均具有低到中等的Mg/Ca、低Sr/Ca的特征,没有明显分组现象;但是钙质生物壳体却根据其在岩石中的结构位置呈现明显的分组现象,基质钙质生物壳体具有高Mg/Ca、中等Sr/Ca的特征,包裹的钙质生物壳体具有低Mg/Ca、中等Sr/Ca的特征。根据碳酸盐矿物和钙质生物壳体的Mg/Ca特征,认为基质钙质生物壳体是在甲烷渗漏环境下钙化的,无机碳酸盐矿物的出现影响了其Mg/Ca;而包裹的钙质生物壳体是在非甲烷渗漏环境下钙化的,由于生物扰动、灌洗等作用以包裹团块的形式保存在碳酸盐岩中。依据Sr/Ca在成岩过程中的变化特点推测最初形成的基质钙质生物壳体可能具有较现在高的Sr/Ca。研究结果在甲烷渗漏信息地球化学指标提取方面具有一定意义。 相似文献
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海底甲烷冷泉特征与冷泉生态系统的群落结构 总被引：6，自引：0，他引：6
海底冷泉及冷泉生态系统是现代海洋地质学和生物学研究的前沿领域,它提升了人类对深海资源的认识和利用,拓展了深海极端环境下生命的潜在界线。综述了海底甲烷冷泉的成因、冷泉喷发的类型及其特征,海底冷泉分布、形成的主要阶段(150—100Ma BP,42—28Ma BP和12Ma BP以来)以及指示海底冷泉系统的简要特征;综述了冷泉化能自养生态系统及其食物链构成和特征,专性种、潜在专性种和非专性种的生物组成及其特征,冷泉环境中有孔虫和轻小型底栖动物的主要变化;最后划分了我国近海的冷泉区(点)并简要介绍它们的分布和特征,为开展我国近海冷泉及其冷泉生物群落的调查和研究提供了基础资料。 相似文献
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Seep‐carbonates (13C‐depleted) are present at different levels within the Miocene terrigenous succession of Deruta (Marnoso‐arenacea Formation, central Italy); they are associated with pebbly sandstones and conglomerates in a tectonically active fan‐delta slope depositional system. Most of these seep‐carbonates are included in slide/slump horizons as scattered blocks. The occurrence of seep‐carbonates is clear evidence of the flow of methane‐rich fluids pervading the sediments. Fluids, probably of biogenic origin, may have reached the sea‐bottom through thrust faults and selectively infiltrated the more permeable coarse‐grained horizons deposited along the slope. Different stages of fluid emissions are documented: slow flux stage, corresponding to the development of large carbonate bodies and dense chemosynthetic communities; and fast fluid flow associated with intense carbonate brecciation, pipes and veins. Large amounts of authigenic carbonates are reworked by slope failures triggered by tectonics and fluids reducing sediment strength; in situ cementation of slide blocks may also have occurred due to remobilization of methane‐rich fluids by mass‐wasting processes. 相似文献
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文章旨在研究南海冷泉来源真菌Talaromyces helicus SCSIO41311中聚酮类次生代谢产物。主要采用正相硅胶柱层析、反相硅胶柱层析、Sephadex LH-20、高效液相色谱(high performance liquid chromatography, HPLC)及薄层色谱(thin layer chromatography, TLC)等多种方法进行分离纯化;通过核磁共振波谱(nuclear magnetic resonance, NMR)、质谱(mass spectrometry,MS)等现代波谱分析方法及理化性质进行结构鉴定。从中分离得到7个聚酮类化合物,分别为:desmethylsulochrin (1)、sulochrin (2)、monomethylsulochrin (3)、circinophoric acid (4)、dimethyl 2,3-dimethylosoate(5)、endocrocin (6)和1-methyl emodin (7)。所有化合物均为首次从深海冷泉微生物中得到,其中化合物1为首次报道其核磁数据。 相似文献
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