摘要详情
86 / 2025-03-31 15:41:48
Pyrite Microtextural Evidence and Multimodal Microbial Mineralization Records in the Qingjiang Fossils
Cambrian; Qingjiang Biota; Framboidal pyrite; Qingjiangonema; Chain-like pyrite
摘要待审
The coevolution of microorganisms and minerals constitutes a pivotal research theme in understanding early life-environment interactions on Earth. Biomineral assemblages formed through such processes offer unique archives for reconstructing deep-time microbial community structures and metabolic networks. Framboidal pyrite, widely regarded as a hallmark product of microbial sulfate reduction in anoxic sedimentary settings (Wilkin & Barnes, 1997), remains contentious regarding microbial regulation of its crystal morphology, spatial distribution, and isotopic fractionation mechanisms.
This study investigates Naraoia fossils from the Early Cambrian Qingjiang Biota in South China, employing multi-scale microscopy and microspectroscopy to decode pyrite morphological and biogenetic features. Micromorphological analyses reveal intricate pyrite differentiation patterns: 4–6 μm spherical pyrites are dispersed within the matrix(Fig.1E), while large-scale aggregates at fossil-rock interfaces—indicative of persistent anoxic bottom-water conditions during deposition of the Shuijingtuo Formation—are categorized into three subtypes: (1) framboidal clusters composed of cubic-octahedral microcrystals (0.5–8 μm, 40%)(Fig.1G), (2) framboids dominated by cubic or octahedral cross-section microcrystals (5–15 μm, 55%)(Fig.1G), and (3) chain-like aggregates with biologically diagnostic architectures (5%).
Notably, chain-type pyrites exhibit two distinct configurations: (i) filamentous structures formed by linearly aligned microcrystals, formally designated as Qingjiangonema ((Fig.1F,Fig.1G),)(Cui et al., 2024), and (ii) the first-reported euhedral octahedral chains reaching up to 800 μm in length(Fig.1H). The microscale morphological precision of these chains surpasses the constraints of inorganic self-organization, strongly suggesting microbial mediation. Future studies integrating sulfur isotope microanalyses will further test the biogenetic hypothesis of chain-like pyrite formation.
References
Wilkin, R.T., & Barnes, H.L. (1997). Formation processes of framboidal pyrite. Geochimica et Cosmochimica Acta, 61(2), 323-339.
Cui, Y., Fu, D., & Dai, T. et al. (2024). The Cambrian microfossil Qingjiangonema reveals the co-evolution of sulfate reducers and oxidizing cable bacteria. Science Advances.
This study investigates Naraoia fossils from the Early Cambrian Qingjiang Biota in South China, employing multi-scale microscopy and microspectroscopy to decode pyrite morphological and biogenetic features. Micromorphological analyses reveal intricate pyrite differentiation patterns: 4–6 μm spherical pyrites are dispersed within the matrix(Fig.1E), while large-scale aggregates at fossil-rock interfaces—indicative of persistent anoxic bottom-water conditions during deposition of the Shuijingtuo Formation—are categorized into three subtypes: (1) framboidal clusters composed of cubic-octahedral microcrystals (0.5–8 μm, 40%)(Fig.1G), (2) framboids dominated by cubic or octahedral cross-section microcrystals (5–15 μm, 55%)(Fig.1G), and (3) chain-like aggregates with biologically diagnostic architectures (5%).
Notably, chain-type pyrites exhibit two distinct configurations: (i) filamentous structures formed by linearly aligned microcrystals, formally designated as Qingjiangonema ((Fig.1F,Fig.1G),)(Cui et al., 2024), and (ii) the first-reported euhedral octahedral chains reaching up to 800 μm in length(Fig.1H). The microscale morphological precision of these chains surpasses the constraints of inorganic self-organization, strongly suggesting microbial mediation. Future studies integrating sulfur isotope microanalyses will further test the biogenetic hypothesis of chain-like pyrite formation.
References
Wilkin, R.T., & Barnes, H.L. (1997). Formation processes of framboidal pyrite. Geochimica et Cosmochimica Acta, 61(2), 323-339.
Cui, Y., Fu, D., & Dai, T. et al. (2024). The Cambrian microfossil Qingjiangonema reveals the co-evolution of sulfate reducers and oxidizing cable bacteria. Science Advances.
重要日期
-
会议日期
06月10日
2025
至06月13日
2025
-
04月15日 2025
初稿截稿日期
主办单位
National Natural Science Foundation of China
Geobiology Society
National Committee of Stratigraphy of China
Ministry of Science and Technology
Geological Society of China
Paleontological Society of China
Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (CAS)
Institute of Vertebrate Paleontology and Paleoanthropology, CAS
International Commission on Stratigraphy
International Paleontological Association
Geobiology Society
National Committee of Stratigraphy of China
Ministry of Science and Technology
Geological Society of China
Paleontological Society of China
Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (CAS)
Institute of Vertebrate Paleontology and Paleoanthropology, CAS
International Commission on Stratigraphy
International Paleontological Association
承办单位
State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences (CUG, Wuhan)
联系方式
- Yizhou Huang
- yi******@cug.edu.cn
- 186********
历届会议
-
2025年06月10日 中国 Wuhan
第五届国际地球生物学会议 -
2017年06月24日 中国 Wuhan,China
The 4th International Conference of Geobiology
