Integrated Stratigraphy and Mineralogy of the Doushantuo Formation in Weng’an, South China, and Implications for Ediacaran Phosphogenesis

Abstract

The Ediacaran–Cambrian Phosphogenic Episode is the Earth’s first true phosphogenic event and resulted in worldwide phosphate deposits, which occurred during the processes of the Neoproterozoic Oxygenation Event. The Ediacaran Doushantuo Formation (ca. 635–551 Ma) of Weng’an area in central Guizhou, South China, contains two economic phosphorite beds (the Lower and Upper Phosphorite Beds). This paper presents a detailed stratigraphic, sedimentological and mineralogical study of multiple outcrop and drill core sections of the Doushantuo Formation across the Weng’an area, and identified 11 lithofacies and 4 types of phosphatic grains. Significant differences in lithofacies and grain types between the upper and lower phosphate deposits are observed, indicating that the two sets of phosphate deposits are the products of two distinct phosphogenic processes. The Lower Phosphorite Bed mainly consists of banded and laminated phosphorites, contains micro-oncoids formed by microbially-mediated precipitation and peloids formed by in-situ chemically oscillating reactions, indicating a biochemical and chemical enrichment of phosphorus to sediments during the Early Ediacaran Period. The Upper Phosphorite Bed is mainly composed of carbonaceous, massive, and stromatolitic phosphorites, contains bioclasts (phosphatized spheroidal fossils), and intraclasts formed by hydrodynamic agitation, suggesting that the major accesses of phosphorus to sediments were the remineralization of organic P. Deposition of the two economic phosphorite beds was controlled by two sea-level cycles. Such differences have also been documented in contemporaneous phosphate-bearing successions in Brazil and Mangolia, indicating a significant shift in global phosphogenic mechanism during the early and middle Ediacaran, which may be due to the changes in redox conditions in seawater, associated with the Neoproterozoic Oxygenation Event. These regional active P-cycle processes could produce more free oxygen, which may have contributed to the upcoming Phanerozoic global oxidation.

Keywords

phosphorite / lithofacies / phosphatic grains / phosphogenic paragenesis / phosphorus cycle / mineralogy

References

[] Abram M B, Holz M. Early to Middle Devonian Ironstone and Phosphorite in the Northwestern Gondwana Parnaíba Basin, Brazil: A Record of an Epeiric Margin Paleoceanographic Changes. Sedimentary Geology, 2020, 402: 105646.

[] Ahmad F, Baioumy H, Farouk S, et al. Geochemistry and Stable Isotopes of the Upper Campanian–Lower Maastrichtian Phosphorite-Bearing Sequence, Central Jordan: Implications for Their Age, Origin, and Diagenesis. Geological Journal, 2020, 55(6): 4453-4468.

[] Algabri M, She Z B, Jiao L X, et al. Apatite-Glaucony Association in the Ediacaran Doushantuo Formation, South China and Implications for Marine Redox Conditions. Precambrian Research, 2020, 347: 105842.

[] Álvaro J J, Shields-Zhou G A, Ahlberg P, et al. Ediacaran-Cambrian Phosphorites from the Western Margins of Gondwana and Baltica. Sedimentology, 2016, 63(2): 350-377.

[] Ammerman J S, Hood R R, Case D A, et al. Phosphorus Deficiency in the Atlantic: An Emerging Paradigm on Oceanography. Eos, Transactions American Geophysical Union, 2003, 84(18): 165-170.

[] Anderson R P, MacDonald F A, Jones D S, et al. Doushantuo-Type Microfossils from Latest Ediacaran Phosphorites of Northern Mongolia. Geology, 2017, 45(12): 1079-1082.

[] Anderson R P, McMahon S, Macdonald F A, et al. Palaeobiology of Latest Ediacaran Phosphorites from the Upper Khesen Formation, Khuvsgul Group, Northern Mongolia. Journal of Systematic Palaeontology, 2019, 17(6): 501-532.

[] Anttila E, MacDonald F, Bold U. Stratigraphy of the Khuvsgul Group, Mongolia. Mongolian Geoscientist, 2021, 26(52): 2-15.

[] Arning E T, Lückge A, Breuer C, et al. Genesis of Phosphorite Crusts off Peru. Marine Geology, 2009, 262(1/2/3/4): 68-81.

[] Banerjee D M, Schidlowski M, Siebert F, et al. Geochemical Changes across the Proterozoic-Cambrian Transition in the Durmala Phosphorite Mine Section, Mussoorie Hills, Garhwal Himalaya, India. Palaeogeography, Palaeoclimatology, Palaeoecology, 1997, 132(1/2/3/4): 183-194.

[] Barfod G H, Albarède F, Knoll A H, et al. New Lu-Hf and Pb-Pb Age Constraints on the Earliest Animal Fossils. Earth and Planetary Science Letters, 2002, 201(1): 203-212.

[] Bertrand-Sarfati J, Flicoteaux R, Moussine-Pouchkine A, et al. Lower Cambrian Apatitic Stromatolites and Phospharenites Related to the Glacio-Eustatic Cratonic Rebound (Sahara, Algeria). SEPM Journal of Sedimentary Research, 1997, 67(5): 957-974.

[] Bjerrum C J, Canfield D E. Ocean Productivity before about 1.9 Gyr ago Limited by Phosphorus Adsorption Onto Iron Oxides. Nature, 2002, 417(6885): 159-162.

[] Bristow T F, Kennedy M J, Derkowski A, et al. Mineralogical Constraints on the Paleoenvironments of the Ediacaran Doushantuo Formation. Proceedings of the National Academy of Sciences of the United States of America, 2009, 106(32): 13190-13195.

[] Caird R A, Pufahl P K, Hiatt E E, et al. Ediacaran Stromatolites and Intertidal Phosphorite of the Salitre Formation, Brazil: Phosphogenesis during the Neoproterozoic Oxygenation Event. Sedimentary Geology, 2017, 350: 55-71.

[] Chen D F, Dong W Q, Zhu B Q, et al. Pb-Pb Ages of Neoproterozoic Doushantuo Phosphorites in South China: Constraints on Early Metazoan Evolution and Glaciation Events. Precambrian Research, 2004, 132(1/2): 123-132.

[] Chen J Y, Bottjer D J, Oliveri P, et al. Small Bilaterian Fossils from 40 to 55 Million Years before the Cambrian. Science, 2004, 305(5681): 218-222.

[] Chen L, Xiao S H, Pang K, et al. Cell Differentiation and Germ–Soma Separation in Ediacaran Animal Embryo-Like Fossils. Nature, 2014, 516(7530): 238-241.

[] Compton J S, Bergh E W. Phosphorite Deposits on the Namibian Shelf. Marine Geology, 2016, 380: 290-314.

[] Condon D, Zhu M Y, Bowring S, et al. U-Pb Ages from the Neoproterozoic Doushantuo Formation, China. Science, 2005, 308(5718): 95-98.

[] Cook P J, Shergold J H. Phosphorus, Phosphorites and Skeletal Evolution at the Precambrian—Cambrian Boundary. Nature, 1984, 308(5956): 231-236.

[] Cook P J. Phosphogenesis around the Proterozoic-Phanerozoic Transition. Journal of the Geological Society, 1992, 149(4): 615-620. in Chinese with English Abstract)

[] Cox G M, Lyons T W, Mitchell R N, et al. Linking the Rise of Atmospheric Oxygen to Growth in the Continental Phosphorus Inventory. Earth and Planetary Science Letters, 2018, 489: 28-36.

[] Creveling J R, Johnston D T, Poulton S W, et al. Phosphorus Sources for Phosphatic Cambrian Carbonates. Geological Society of America Bulletin, 2014, 126(1/2): 145-163.

[] Dodd M S, Papineau D, She Z B, et al. Organic Remains in Late Palaeoproterozoic Granular Iron Formations and Implications for the Origin of Granules. Precambrian Research, 2018, 310: 133-152.

[] Dorjnamjaa D. Neoproterozoic–Cambrian Biostratigraphy of the Ancient Phosphate Basins of Mongolia and the Influence of Bacterial Communities on Phosphorite Accumulation: A Review. International Journal of Agriculture Innovations and Research, 2016, 5(3): 372-384.

[] Drummond J B R, Pufahl P K, Porto C G, et al. Neoproterozoic Peritidal Phosphorite from the Sete Lagoas Formation (Brazil) and the Precambrian Phosphorus Cycle. Sedimentology, 2015, 62(7): 1978-2008.

[] Felitsyn S B, Bogomolov E S. Nd Isotope Composition of the Ediacaran and Earliest Cambrian Phosphorite Nodules and Fe Sulphide from the East European Platform. Geological Magazine, 2020, 157(12): 2081-2088.

[] Filippelli G M. The Global Phosphorus Cycle: Past, Present, and Future. Elements, 2008, 4(2): 89-95.

[] Flicoteaux R, Trompette R. Cratonic and Foreland Early Cambrian Phosphorites of West Africa: Palaeoceanographical and Climatical Contexts. Palaeogeography, Palaeoclimatology, Palaeoecology, 1998, 139(3/4): 107-120.

[] Föllmi K B. The Phosphorus Cycle, Phosphogenesis and Marine Phosphate-Rich Deposits. Earth-Science Reviews, 1996, 40(1/2): 55-124.

[] Gan T, Luo T Y, Pang K, et al. Cryptic Terrestrial Fungus-Like Fossils of the Early Ediacaran Period. Nature Communications, 2021, 12(1): 1-12.

[] Hein J R, Perkins R B, McIntyre B R. Chapter 2 Evolution of Thought Concerning the Origin of the Phosphoria Formation, Western us Phosphate Field, 2004 Amsterdam Elsevier 19-42.

[] Ilyin A V, Heinsalu H N. Early Ordovician Shelly Phosphorites of the Baltic Phosphate Basin. Geological Society, London, Special Publications, 1990, 52(1): 253-259.

[] Jiang G Q, Kaufman A J, Christie-Blick N, et al. Carbon Isotope Variability across the Ediacaran Yangtze Platform in South China: Implications for a Large Surface-to-Deep Ocean δ¹³C Gradient. Earth and Planetary Science Letters, 2007, 261(1/2): 303-320.

[] Jiang G Q, Shi X Y, Zhang S H, et al. Stratigraphy and Paleogeography of the Ediacaran Doushantuo Formation (Ca. 635–551 Ma) in South China. Gondwana Research, 2011, 19(4): 831-849.

[] Jiang G, Kennedy M J, Christie-Blick N, et al. Stratigraphy, Sedimentary Structures, and Textures of the Late Neoproterozoic Doushantuo Cap Carbonate in South China. Journal of Sedimentary Research, 2006, 76: 978-995.

[] Kametaka M, Takebe M, Nagai H, et al. Sedimentary Environments of the Middle Permian Phosphorite-Chert Complex from the Northeastern Yangtze Platform, China; The Gufeng Formation: A Continental Shelf Radiolarian Chert. Sedimentary Geology, 2005, 174(3/4): 197-222.

[] Kholodov V, Paul R K. Geochemistry and Metallogeny of Phosphorus in the Russian Platform during the Jurassic–Cretaceous. Lithology and Mineral Resources, 2001, 36: 195-210.

[] Krajewski K P. The Botneheia Formation (Middle Triassic) in Edgeøya and Barentsøya, Svalbard: Lithostratigraphy, Facies, Phosphogenesis, Paleoenvironment. Polish Polar Research, 2008, 29(4): 319-364.

[] Krajewski K, Karcz P, Wozny E, et al. Type Section of the Bravaisberget Formation (Middle Triassic) at Bravaisberget, Western Nathorst Land, Spitsbergen, Svalbard. Polish Polar Research, 2007, 28(2): 79-122.

[] Laakso T A, Sperling E A, Johnston D T, et al. Ediacaran Reorganization of the Marine Phosphorus Cycle. Proceedings of the National Academy of Sciences of the United States of America, 2020, 117(22): 11961-11967.

[] Larina E, Bottjer D J, Corsetti F A, et al. Uppermost Triassic Phosphorites from Williston Lake, Canada: Link to Fluctuating Euxinic-Anoxic Conditions in Northeastern Panthalassa before the End-Triassic Mass Extinction. Scientific Reports, 2019, 9: 18790.

[] Lenton T M, Boyle R A, Poulton S W, et al. Co-Evolution of Eukaryotes and Ocean Oxygenation in the Neoproterozoic Era. Nature Geoscience, 2014, 7(4): 257-265.

[] Li C, Hardisty D S, Luo G, et al. Uncovering the Spatial Heterogeneity of Ediacaran Carbon Cycling. Geobiology, 2017, 15(2): 211-224.

[] Li C, Love G D, Lyons T W, et al. A Stratified Redox Model for the Ediacaran Ocean. Science, 2010, 328(5974): 80-83.

[] Liu P J, Xiao S H, Yin C Y, et al. Systematic Description and Phylogenetic Affinity of Tubular Microfossils from the Ediacaran Doushantuo Formation at Weng’an, South China. Palaeontology, 2008, 51(2): 339-366.

[] Liu Z R R, Zhou M F. Meishucun Phosphorite Succession (SW China) Records Redox Changes of the Early Cambrian Ocean. GSA Bulletin, 2017, 129:1554-1567.

[] Liu Z R R, Zhou M F. Early Cambrian Ocean Mixing Recorded by Phosphorite Successions in the Nanhua Basin, South China. Precambrian Research, 2020, 349: 105414.

[] Mazumdar A, Banerjee D M, Schidlowski M, et al. Rare-Earth Elements and Stable Isotope Geochemistry of Early Cambrian Chert-Phosphorite Assemblages from the Lower Tal Formation of the Krol Belt (Lesser Himalaya, India). Chemical Geology, 1999, 156(1/2/3/4): 275-297.

[] McFadden K A, Huang J, Chu X L, et al. Pulsed Oxidation and Biological Evolution in the Ediacaran Doushantuo Formation. Proceedings of the National Academy of Sciences of the United States of America, 2008, 105(9): 3197-3202.

[] Muscente A D, Hawkins A D, Xiao S H. Fossil Preservation through Phosphatization and Silicification in the Ediacaran Doushantuo Formation (South China): A Comparative Synthesis. Palaeogeography, Palaeoclimatology, Palaeoecology, 2015, 434: 46-62.

[] Nelson G J, Pufahl P K, Hiatt E E. Paleoceanographic Constraints on Precambrian Phosphorite Accumulation, Baraga Group, Michigan, USA. Sedimentary Geology, 2010, 226(1/2/3/4): 9-21.

[] Ogihara S. Geochemical Characteristics of Phosphorite and Carbonate Nodules from the Miocene Funakawa Formation, Western Margin of the Yokote Basin, Northeast Japan. Sedimentary Geology, 1999, 125(1/2): 69-82.

[] Ounis A, Kocsis L, Chaabani F, et al. Rare Earth Elements and Stable Isotope Geochemistry (δ¹³C and δ¹⁸O) of Phosphorite Deposits in the Gafsa Basin, Tunisia. Palaeogeography, Palaeoclimatology, Palaeoecology, 2008, 268(1/2): 1-18.

[] Ouyang Q, Zhou C M, Xiao S H, et al. Distribution of Ediacaran Acanthomorphic Acritarchs in the Lower Doushantuo Formation of the Yangtze Gorges Area, South China: Evolutionary and Stratigraphic Implications. Precambrian Research, 2021, 353: 106005.

[] Papineau D. Global Biogeochemical Changes at both Ends of the Proterozoic: Insights from Phosphorites. Astrobiology, 2010, 10(2): 165-181.

[] Papineau D. Chemically Oscillating Reactions in the Formation of Botryoidal Malachite. American Mineralogist, 2020, 105(4): 447-454.

[] Papineau D, de Gregorio B, Fearn S, et al. Nanoscale Petrographic and Geochemical Insights on the Origin of the Palaeoproterozoic Stromatolitic Phosphorites from Aravalli Supergroup, India. Geobiology, 2016, 14(1): 3-32.

[] Papineau D, Purohit R, Fogel M L, et al. High Phosphate Availability as a Possible Cause for Massive Cyanobacterial Production of Oxygen in the Paleoproterozoic Atmosphere. Earth and Planetary Science Letters, 2013, 362: 225-236.

[] Papineau D, She Z B, Dodd M S. Chemically-Oscillating Reactions during the Diagenetic Oxidation of Organic Matter and in the Formation of Granules in Late Palaeoproterozoic Chert from Lake Superior. Chemical Geology, 2017, 470: 33-54.

[] Planavsky N J, Rouxel O J, Bekker A, et al. The Evolution of the Marine Phosphate Reservoir. Nature, 2010, 467(7319): 1088-1090.

[] Poulton T P, Aitken J D. The Lower Jurassic Phosphorites of Southeastern British Columbia and Terrane Accretion to Western North America. Canadian Journal of Earth Sciences, 1989, 26(8): 1612-1616.

[] Pufahl P K, Grimm K A. Coated Phosphate Grains: Proxy for Physical, Chemical, and Ecological Changes in Seawater. Geology, 2003, 31(9): 801-804.

[] Pufahl P K, Groat L A. Sedimentary and Igneous Phosphate Deposits: Formation and Exploration: An Invited Paper. Economic Geology, 2017, 112(3): 483-516.

[] Reinhard C T, Planavsky N J, Gill B C, et al. Evolution of the Global Phosphorus Cycle. Nature, 2017, 541(7637): 386-389.

[] Sahoo S K, Planavsky N J, Jiang G, et al. Oceanic Oxygenation Events in the Anoxic Ediacaran Ocean. Geobiology, 2016, 14(5): 457-468.

[] Sahoo S K, Planavsky N J, Kendall B, et al. Ocean Oxygenation in the Wake of the Marinoan Glaciation. Nature, 2012, 489(7417): 546-549.

[] Salama W, El-Kammar A, Saunders M, et al. Microbial Pathways and Palaeoenvironmental Conditions Involved in the Formation of Phosphorite Grains, Safaga District, Egypt. Sedimentary Geology, 2015, 325: 41-58.

[] Salama W, Khirekesh Z, Amini A, et al. Diagenetic Evolution of the Upper Devonian Phosphorites, Alborz Mountain Range, Northern Iran. Sedimentary Geology, 2018, 376: 90-112.

[] Sanders C, Grotzinger J. Sedimentological and Stratigraphic Constraints on Depositional Environment for Ediacaran Carbonate Rocks of the São Francisco Craton: Implications for Phosphogenesis and Paleoecology. Precambrian Research, 2021, 363: 106328.

[] Schöllhorn I, Houben A, Gertsch B, et al. Enhanced Upwelling and Phosphorite Formation in the Northeastern Pacific during the Late Oligocene: Depositional Mechanisms, Environmental Conditions, and the Impact of Glacio-Eustacy. Geological Society of America Bulletin, 2019, 132(3–4): 687-709.

[] Schwid M F, Xiao S H, Hiatt E E, et al. Iron Phosphate in the Ediacaran Doushantuo Formation of South China: A Previously Undocumented Marine Phosphate Sink. Palaeogeography, Palaeoclimatology, Palaeoecology, 2020, 560: 109993.

[] She Z, Strother P, Mcmahon G, et al. Terminal Proterozoic Cyanobacterial Blooms and Phosphogenesis Documented by the Doushantuo Granular Phosphorites I: In situ Micro-Analysis of Textures and Composition. Precambrian Research, 2013, 235(3): 20-35.

[] She Z B, Strother P, Papineau D. Terminal Proterozoic Cyanobacterial Blooms and Phosphogenesis Documented by the Doushantuo Granular Phosphorites II: Microbial Diversity and C Isotopes. Precambrian Research, 2014, 251: 62-79.

[] She Z B, Zhang Y T, Liu W, et al. New Observations of Ambient Inclusion Trails (AITs) and Pyrite Framboids in the Ediacaran Doushantuo Formation, South China. Palaeogeography, Palaeoclimatology, Palaeoecology, 2016, 461: 374-388.

[] Shields-Zhou G, Och L. The Case for a Neoproterozoic Oxygenation Event: Geochemical Evidence and Biological Consequences. GSA Today, 2011, 21(3): 4-11.

[] Silva P L, Bustin R M. Significance and Distribution of Apatite in the Triassic Doig Phosphate Zone, Western Canada Sedimentary Basin. Minerals, 2020, 10(10): 904.

[] Song X, Zeng D, Cai J, et al. Geological Characteristics and Ore-Controlling Factors of No. II Ore Body of Yingping Phosphate Deposit, Guizhou Province. Mineral Exploration, 2020, 11(1): 136 149 (in Chinese with English Abstract)

[] Soudry D. Primary Bedded Phosphorites in the Campanian Mishash Formation, Negev, Southern Israel. Sedimentary Geology, 1992, 80(1/2): 77-88.

[] Soudry D, Southgat P N. Ultrastructure of a Middle Cambrian Primary Nonpelletal Phosphorite and Its Early Transformation into Phosphate Vadoids: Georgina Basin, Australia. SEPM Journal of Sedimentary Research, 1989, 59(1): 53-64.

[] Swett K, Crowder R K. Primary Phosphatic Oolites from the Lower Cambrian of Spitsbergen. SEPM Journal of Sedimentary Research, 1982, 52(2): 587-593.

[] Tucker M E, Wright V P. Carbonate Sedimentology, 1990 Oxford Blackwell Science.

[] Tyrrell T. The Relative Influences of Nitrogen and Phosphorus on Oceanic Primary Production. Nature, 1999, 400(6744): 525-531.

[] Wang J S, Jiang G Q, Xiao S H, et al. Carbon Isotope Evidence for Widespread Methane Seeps in the ca. 635 Ma Doushantuo Cap Carbonate in South China. Geology, 2008, 36(5): 347.

[] Wang W, Guan C, Zhou C, et al. Integrated Carbon, Sulfur, and Nitrogen Isotope Chemostratigraphy of the Ediacaran Lantian Formation in South China: Spatial Gradient, Ocean Redox Oscillation, and Fossil Distribution. Geobiology, 2017, 15(4): 552-571.

[] Wang X C, Li X H, Li Z X, et al. Episodic Precambrian Crust Growth: Evidence from U-Pb Ages and Hf-O Isotopes of Zircon in the Nanhua Basin, Central South China. Precambrian Research, 2012, 222/223: 386-403.

[] Wang Z C, Liu J J, Jiang H, et al. Lithofacies Paleogeography and Exploration Significance of Sinian Doushantuo Depositional Stage in the Middle–Upper Yangtze Region, Sichuan Basin, SW China. Petroleum Exploration and Development, 2019, 46(1): 41-53.

[] Wigley R A, Compton J S. Microstratigraphy of a Miocene Layered Phosphatic Pebble from the Western Margin of South Africa. Sedimentology, 2013, 60(3): 666-678.

[] Xiao S. New Multicellular Algal Fossils and Acritarchs in Doushantuo Chert Nodules (Neoproterozoic; Yangtze Gorges, South China). Journal of Paleontology, 2004, 78(2): 393-401.

[] Xiao S H, Bykova N, Kovalick A, et al. Stable Carbon Isotopes of Sedimentary Kerogens and Carbonaceous Macrofossils from the Ediacaran Miaohe Member in South China: Implications for Stratigraphic Correlation and Sources of Sedimentary Organic Carbon. Precambrian Research, 2017, 302: 171-179.

[] Xiao S H, McFadden K A, Peek S, et al. Integrated Chemostratigraphy of the Doushantuo Formation at the Northern Xiaofenghe Section (Yangtze Gorges, South China) and Its Implication for Ediacaran Stratigraphic Correlation and Ocean Redox Models. Precambrian Research, 2012, 192/193/194/195: 125-141.

[] Xiao S H, Zhang Y, Knoll A H. Three-Dimensional Preservation of Algae and Animal Embryos in a Neoproterozoic Phosphorite. Nature, 1998, 391(6667): 553-558.

[] Xiao S H, Zhou C M, Liu P J, et al. Phosphatized Acanthomorphic Acritarchs and Related Microfossils from the Ediacaran Doushantuo Formation at Weng’an (South China) and Their Implications for Biostratigraphic Correlation. Journal of Paleontology, 2014, 88(1): 1-67.

[] Xiao S, Knoll A H. Phosphatized Animal Embryos from the Neoproterozoic Doushantuo Formation at Weng’an, Guizhou, South China. Journal of Paleontology, 2000, 74(5): 767-788.

[] Yang H Y, Xiao J F, Xia Y, et al. Origin of the Ediacaran Weng’an and Kaiyang Phosphorite Deposits in the Nanhua Basin, SW China. Journal of Asian Earth Sciences, 2019, 182: 103931.

[] Yang H Y, Xiao J F, Xia Y, et al. Phosphorite Generative Processes around the Precambrian-Cambrian Boundary in South China: An Integrated Study of Mo and Phosphate O Isotopic Compositions. Geoscience Frontiers, 2021, 12(5): 101187.

[] Yang H Y, Xiao J F, Xia Y, et al. Diagenesis of Ediacaran—Early Cambrian Phosphorite: Comparisons with Recent Phosphate Sediments Based on LA-ICP-MS and EMPA. Ore Geology Reviews, 2022, 144: 104813.

[] Yin C Y, Tang F, Liu Y Q, et al. U-Pb Zircon Age from the Base of the Ediacaran Doushantuo Formation in the Yangtze Gorges, South China: Constraint on the Age of Marinoan Glaciation. Episodes, 2005, 28(1): 48-51.

[] Yin Z J, Zhu M Y, Davidson E H, et al. Sponge Grade Body Fossil with Cellular Resolution Dating 60 Myr before the Cambrian. Proceedings of the National Academy of Sciences of the United States of America, 2015, 112(12): E1453-E1460.

[] Yuan X L, Chen Z, Xiao S H, et al. An Early Ediacaran Assemblage of Macroscopic and Morphologically Differentiated Eukaryotes. Nature, 2011, 470(7334): 390-393.

[] Zarasvandi A, Fereydouni Z, Pourkaseb H, et al. Geochemistry of Trace Elements and Their Relations with Organic Matter in Kuh-e-Sefid Phosphorite Mineralization, Zagros Mountain, Iran. Ore Geology Reviews, 2019, 104: 72-87.

[] Zhang S H, Jiang G Q, Zhang J M, et al. U-Pb Sensitive High-Resolution Ion Microprobe Ages from the Doushantuo Formation in South China: Constraints on Late Neoproterozoic Glaciations. Geology, 2005, 33(6): 473-476.

[] Zhang Y G, Pufahl P K, Du Y S, et al. Economic Phosphorite from the Ediacaran Doushantuo Formation, South China, and the Neoproterozoic–Cambrian Phosphogenic Event. Sedimentary Geology, 2019, 388: 1-19.

[] Zhang Y L, Li Z Y, Dini S M, et al. Origin and Evolution of the Late Cretaceous Reworked Phosphorite in the Sirhan-Turayf Basin, Northern Saudi Arabia. Minerals, 2021, 11(4): 350.

[] Zhou C M, Guan C G, Cui H, et al. Methane-Derived Authigenic Carbonate from the Lower Doushantuo Formation of South China: Implications for Seawater Sulfate Concentration and Global Carbon Cycle in the Early Ediacaran Ocean. Palaeogeography, Palaeoclimatology, Palaeoecology, 2016, 461: 145-155.

[] Zhou C M, Li X H, Xiao S H, et al. A New SIMS Zircon U-Pb Date from the Ediacaran Doushantuo Formation: Age Constraint on the Weng’an Biota. Geological Magazine, 2017, 154(6): 1193-1201.

[] Zhu M Y, Lu M, Zhang J M, et al. Carbon Isotope Chemostratigraphy and Sedimentary Facies Evolution of the Ediacaran Doushantuo Formation in Western Hubei, South China. Precambrian Research, 2013, 225: 7-28.

[] Zhu M Y, Zhang J M, Yang A H. Integrated Ediacaran (Sinian) Chronostratigraphy of South China. Palaeogeography, Palaeoclimatology, Palaeoecology, 2007, 254(1/2): 7-61.