Carbon Isotopic Signatures of Individual Archean Microfossils(?) from Western Australia
Carbon Isotopic Signatures of Individual Archean Microfossils(?) from Western Australia
复制标题
西澳大利亚单个太古代微化石（？）的碳同位素特征
DOI：
10.1080/00206810109465008
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发表时间：
2001
影响因子：
2.6
通讯作者：
S. Maruyama
中科院分区：
文献类型：
--
作者：
Y. Ueno;Y. Isozaki;H. Yurimoto;S. Maruyama
在西澳大利亚~3.5 Ga北极地区的两个新地点的硅矿脉中发现了新型碳质丝状微结构。它们的碳同位素组成是通过二次离子质谱法原位测量的。碳质丝宽约 1μm，长 10 至 100μm，并在细粒（约 1μm）二氧化硅基质中全矿化。它们在形态上分为三种类型（即螺旋、线状和分支丝）。它们的大小和形态类似于现代和之前报道的化石细菌。这些相似性及其复杂的三维几何形状表明它们可能代表形态上保存完好的细菌化石。 δ13C values of the carbonaceous filaments range from −42 to −32‰, which strongly suggest that they are composed of biologically fixed organic compounds, possibly via the reductive acetyl-CoA pathway or the Calvin cycle.这与太古代地球上已经存在自养生物的假设是一致的。
New types of carbonaceous filamentous microstructures have been identified in silica veins at two new localities in the ∼3.5 Ga North Pole area of Western Australia. Their carbon isotopic compositions were measured in situ by secondary-ion mass spectrometry. The carbonaceous filaments are ∼1μm wide, 10 to 100 μm long, and are permineralized in a fine-grained (∼1 μm) silica matrix. They are morphologically divided into three types (i.e., spiral, threadlike, and branched filaments). Their sizes and morphologies resemble modern and previously reported fossil bacteria. These similarities and their complex three-dimensional geometry suggest that they may represent morphologically preserved fossil bacteria. δ13C values of the carbonaceous filaments range from −42 to −32‰, which strongly suggest that they are composed of biologically fixed organic compounds, possibly via the reductive acetyl-CoA pathway or the Calvin cycle. This is consistent with the hypothesis that autotrophs already existed on the Archean Earth.