Characteristics and formation mechanism of iron-bearing ooids of the Cambrian Mantou Formation in Weihui area,northern Henan Province
XU Ganxiao1, QI Yong'an1,2, HE Wenyi1, DU Yaogang1, LIU Xiaomei1
1 School of Resources and Environment,Henan Polytechnic University,Henan Jiaozuo 454003,China; 2 International Joint Laboratory for Biogenic Traces and Sedimentary Minerals of Henan Province,Henan Jiaozuo 454003,China
Abstract：Oolitic limestone is an important type of carbonate rocks in the Cambrian period,with calcite and dolomitic ooids being the most common. While there have been numerous studies on the formation of these ooids,the occurrence of iron-bearing ooids in the Cambrian is rare and the formation mechanism remains unclear. The iron-bearing ooids of the Cambrian Mantou Formation in the Weihui area of Henan Province were systematically analyzed using sedimentology,sedimentary paleogeography,mineralogy and geochemistry. They can be divided into microsparry iron-bearing ooids and sparry iron ooids,which were formed in the transition zone between the oolitic shoal and back-shoal microbial bioherm of a limited sea in Shanxi and Henan Provinces. The geochemical tests and microscopic observations of iron-bearing ooids indicate that the iron minerals are idiomorphic crystals of hematites with irregular morphology and serrated edges,with no other iron minerals present. The contents of major elements such as Ca,Fe,Al and Si in the samples are high,showing a significant positive correlation between Fe and Al. The abundance and variation trend of trace elements resemble those found in the Earth's crust. The total amount of rare earth elements is high,with a deficiency in light rare earth elements,and an enrichment in heavy rare earth elements. There is no obvious Eu anomaly. These characteristics indicate that the iron minerals in iron-bearing ooids originate from terrestrial detrital input. The analysis of mineralogy and sedimentary palaeogeography of iron-bearing ooids reveals that the iron-bearing minerals likely formed in the study area as a result of the precipitation of Fe(OH)3 colloidal solution from the Ordos land with runoff. Three conditions are necessary for the formation of iron-bearing ooids in the Mantou Formation of the study area: continuous supply of Fe(OH)3 colloidal solution from terrestrial source,iron enrichment in a semi-enclosed coastal bay environment,and continuous oxidation of iron minerals under the hydrodynamic conditions of regular agitation. During oolitic formation,the intermittent input of iron elements from terrestrial weathering leads to the development of alternating laminae of hematite and illite-bearing calcite,which interbed with calcite lamina lacking hematite crystals to form microsparry iron-bearing ooids. If the iron supply is sufficient,sparry iron ooids are formed,characterized by hematite lamina interbedded with calcite lamina. These findings are crucial for understanding the paleo-marine environment and atmospheric environment during the geological period,with significant theoretical and practical implications for the development and utilization of iron deposits.
XU Ganxiao,QI Yong'an,HE Wenyi et al. Characteristics and formation mechanism of iron-bearing ooids of the Cambrian Mantou Formation in Weihui area,northern Henan Province[J]. JOPC, 2024, 26(4): 863-879.
[1] 曹瑞骥. 1986. 藻类在含铁叠层石成因中的作用. 微体古生物学报, 3(2): 185-192,237-238. [Cao R J.1986. On the role of algae in the origin of iron-bearing stromatolites. Acta Micropalaeontologica Sinica, 3(2): 185-192,237-238] [2] 陈思,曾敏,田景春,任科法,靳晓雨,李晨伟. 2021. 扬子台地西南部奥陶系宝塔组底部含鲕绿泥石灰岩成因意义. 地球科学, 46(9): 3107-3122. [Chen S,Zeng M,Tian J C,Ren K F,Jin X Y,Li C W.2021. Chamosite-ooidal limestones at the bottom of Ordovician Pagoda Formation in the southwestern Yangtze platform: genesis and paleoenvironmental implications. Earth Science, 46(9): 3107-3122] [3] 杜汝霖,胡华滨,刘志利. 1999. 冀西北长城系宣龙式铁矿生物成矿作用. 北京: 科学出版社,1-160. [Du R,Hu H B,Liu Z L.1999. Biomineralization of the Changchengian Xuanlong Type Iron Ore Deposit in Northwestern Hebei Province. Beijing: Science Press,1-160] [4] 冯世博,姜玥璐,蔡中华,曾艳华,周进. 2019. 海洋环境中铁的来源、微生物作用过程及生态效应. 地球科学进展, 34(5): 513-522. [Feng S B,Jiang Y L,Cai Z H,Zeng Y H,Zhou J.2019. The state of arts: sources,microbial processes and ecological effects of iron in the marine environment. Advances in Earth Science, 34(5): 513-522] [5] 冯增昭,彭勇民,金振奎,鲍志东. 2004. 中国寒武纪和奥陶纪岩相古地理. 北京: 石油工业出版社, 1-233. [Feng Z Z,Peng Y M,Jin Z K,Bao Z D.2004. Lithofacies Paleogeography of the Cambrian and Ordovician in China. Petroleum Industry Press,1-233] [6] 甘凯,吴昌志,杨涛,刘浩存,叶辉,向萌,刘家润,李伟强. 2021. 鲕状铁建造的特征与形成机制: 以鄂西泥盆系火烧坪铁矿床为例. 地质学报, 95(8): 2493-2508. [Gan K,Wu C Z,Yang T,Liu H C,Ye H,Xiang M,Liu J R,Li W Q.2021. Characteristics and formation mechanism of ooidal iron stones: indications from the Huoshaoping iron deposit,western Hubei Province,China. Acta Geologica Sinica, 95(8): 2493-2508] [7] 李飞,武思琴,刘柯. 2015. 鲕粒原生矿物识别及对海水化学成分变化的指示意义. 沉积学报, 33(3): 500-511. [Li F,Wu S Q,Liu K.2015. Identification of ooid primary mineralogy: a clue for understanding the variation in paleooceanic chemistry. Acta Sedimentologica Sinica, 33(3): 500-511] [8] 李靖博,齐永安,刘小梅,代明月,何雯逸,许旰潇,杜耀刚. 2023. 河南卫辉地区寒武系苗岭统馒头组二段中的铁质叠层石. 微体古生物学报, 40(4): 297-307. [Li J B,Qi Y A,Liu X M,Dai M Y,He W Y,Xu G X,Du Y G.2023. The ferruginous stromatolites form the Member II of the Mantou Formation(Cambrian,Miaolingian)in Weihui,Henan. Acta Micropalaeontologica Sinica, 40(4): 297-307] [9] 李明,林宝玉. 2022. 北京西山寒武纪海相红层的分布与时代. 地质学报, 96(6): 1895-1921. [Li M,Lin B Y.2022. Distribution and ages of the Cambrian marine red beds from Western Hills,Beijing. Acta Geologica Sinica, 96(6): 1895-1921] [10] 李志红,朱祥坤. 2012. 河北省宣龙式铁矿的地球化学特征及其地质意义. 岩石学报, 28(9): 2903-2911. [Li Z H,Zhu X K.2012. Geochemical features of Xuanlong type iron ore deposit in Hebei Province and their geological significances. Acta Petrologica Sinica, 28(9): 2903-2911] [11] 廖士范,魏梁鸿,刘成德,张学寿,冉崇英,史清琴. 1993. 中国泥盆纪鲕铁石沉积环境、成因. 沉积学报, 11(1): 93-102. [Liao S F,Wei L H,Liu C D,Zhang X S,Ran C Y,Shi Q Q.1993. Sedimentary environments and origin of the Devonian oolitic ironstones in China. Acta Sedimentologica Sinica, 11(1): 93-102] [12] 栾晓聪,吴荣昌,王光旭,魏鑫,詹仁斌. 2022. 浅谈华南上扬子区中奥陶统铁质鲕粒沉积. 地层学杂志, 46(1): 23-39. [Luan X C,Wu R C,Wang G X,Wei X,Zhan R B.2022. A brief discussion on the Middle Ordovician ferruginous ooidal deposits in the Upper Yangtze Region,South China. Journal of Stratigraphy, 46(1): 23-39] [13] 倪子尧,徐绪东,陈政安,李凤杰. 2019. 龙门山地区北川石沟里泥盆系养马坝组铁质鲕粒沉积及其环境分析. 沉积学报, 37(4): 702-712. [Ni Z Y,Xu X D,Chen Z A,Li F J.2019. The oolitic iron deposits and environmental analysis of the Devonian Yangmaba Formation in the Shigouli profile,Beichuan County,Longmenshan area. Acta Sedimentologica Sinica, 37(4): 702-712] [14] 裴放,张海清,阎国顺,席运宏. 2008. 河南省地层古生物研究第三分册: 早古生代(华北型). 郑州: 黄河水利出版社,22-26. [Pei F,Zhang H Q,Yan G S,Xi Y H.2008. Early Paleozoic of Stratigraphic Paleontology Research in Henan Province: North China Type(Volume 3). Zhengzhou: Yellow River Conservancy Press,22-26] [15] 裴放,王建平,王世炎,巴燕,陈瑞保. 2012. 河南省中寒武世岩相古地理. 古地理学报, 14(4): 423-436. [Pei F,Wang J P,Wang S Y,Ba Y,Chen R B.2012. The Middle Cambrian lithofacies palaeogeography in Henan Province. Journal of Palaeogeography(Chinese Edition), 14(4): 423-436] [16] 沈健伟. 1994. 贵州及邻区中奥陶世早期沉积物中鲕绿泥石鲕和海绿石的时序位置和环境意义. 贵州地质, 11(3): 207-217. [Shen J W.1994. The temporal location and environmental significance of Zhongmian chlorite and glauconite in early Middle Ordovician sediments in Guizhou and adjacent areas. Guizhou Geology, 11(3): 207-217] [17] 汤冬杰,史晓颖,刘典波,林倚天,张传恒,宋高源,吴金键. 2015. 华北古元古代末鲕铁岩: Columbia超大陆裂解初期的沉积响应. 地球科学, 40(2): 290-304. [Tang D J,Shi X Y,Liu D B,Lin Y T,Zhang C H,Song G Y,Wu J J.2015. Terminal paleoproterozoic ooidal ironstone from North China: a sedimentary response to the initial breakup of Columbia Supercontinent. Earth Science, 40(2): 290-304] [18] 武向峰,伊海生,惠博,杨伟,杜秋定. 2010. 四川龙门山马角坝组铁质鲕粒成因及沉积环境. 沉积与特提斯地质, 30(1): 25-31. [Wu X F,Yin H S,Hui B,Yang W,Du Q D.2010. Genesis and sedimentary environments of the ferruginous ooids from the Majiaoba Formation in northern Longmen Mountains,Sichuan. Sedimentary Geology and Tethyan Geology, 30(1): 25-31] [19] 伊海生,林金辉,赵西西,周恳恳,李军鹏,黄华谷. 2008. 西藏高原沱沱河盆地渐新世—中新世湖相碳酸盐岩稀土元素地球化学特征与正铕异常成因初探. 沉积学报, 26(1): 1-10. [Yi H S,Lin J H,Zhao X X,Zhou K K,Li J P,Huang H G.2008. Geochemistry of rare earth elements and origin of positive europium anomaly in Miocene-Oligocene lacustrine carbonates from Tuotuohe Basin of Tibetan Plateau. Acta Sedimentologica Sinica, 26(1): 1-10] [20] 赵东旭. 1994. 宣龙铁矿铁质鲕粒的显微结构及成因. 地质科学, 29(1): 71-77. [Zhao D X.1994. Microstructures of ferruginous oolite and their genetic characteristics in the Xuanlong iron deposit Hebei Province. Scientia Geologica Sinica, 29(1): 71-77] [21] 赵一鸣,毕承思. 2000. 宁乡式沉积铁矿床的时空分布和演化. 矿床地质, 19(4): 350-362. [Zhao Y M,Bi C S.2000. Time-space distribution and evolution of the Ningxiang type sedimentary iron deposits. Mineral Deposits, 19(4): 350-362] [22] 周家云,郑荣才,张裕书,朱志敏,李潇雨,罗丽萍,周满庚. 2009. 华南泥盆纪古地理环境对宁乡式铁矿床时空分布、矿石特征的制约. 地质科技情报, 28(1): 93-98. [Zhou J Y,Zheng R C,Zhang Y S,Zhu Z M,Li X Y,Luo L P,Zhou M G.2009. Constraints of south China Devonian Ningxiang palaeogeography on the temporal and spatial distribution of iron ore deposits and their characteristics. Geological Science and Technology Information, 28(1): 93-98] [23] Baioumy H,Omran M,Fabritius T.2017. Mineralogy,geochemistry and the origin of high-phosphorus oolitic iron ores of Aswan,Egypt. Ore Geology Reviews, 80: 185-199. [24] Bau M,Dulski P.1996. Distribution of yttrium and rare-earth elements in the Penge and Kuruman iron formation,Transvaal Supergroup,South Africa. Precambrian Research, 79: 37-55. [25] Bekker A,Planavsky N J,Krapež B,Rasmussen B,Hofmann A,Slack J F,Rouxel O J,Konhauser K O.2014. Iron formations: their origins and implications for ancient seawater chemistry. In: Holland H D,Turekian K K(eds). Treatise on Geochemistry(Second Edition). Oxford: Elsevier,561-628. [26] Boucot A J,Chen X,Scotese C R.2013. Phanerozoic paleoclimate: an atlas of lithologic indicators of climate. SEPM Concepts in Sedimentology and Paleontology, 11: 478. [27] Boyle E A,Edmond J M,Sholkovitz E R.1977. The mechanism of iron removal in estuaries. Geochimica et Cosmochimica Acta, 41: 1313-1324. [28] Chu Z Y,Qiu Y F,Zhou X Q,Yang X L,PengP,Zhao T P,Xu J F.2023. Re-Os,Sr-Nd isotopic and PGE elemental constraints for the formation of mid-Proterozoic ironstones in North China Craton: implications for the atmospheric oxygen level. Earth and Planetary Science Letters, 621: 118367. [29] Clement A M,Tackett L S,Ritterbush K A,Ibarra Y.2020. Formation and stratigraphic facies distribution of early Jurassic iron oolite deposits from west central Nevada,USA. Sedimentary Geology, 395: 105537. [30] Danielson A,Möller P,Dulski P.1992. The europium anomalies in banded iron formations and the thermal history of the oceanic crust. Chemical Geology, 97: 89-100. [31] Lazăr I,Grădinaru M.2014. Paleoenvironmental context and paleoecological significance of unique agglutinated polychaete worm tube-ferruginous microstromatolite assemblages from the Middle Jurassic of the Southern Carpathians(Romania). Facies, 60: 515-540. [32] Lin Y T,Tang D J,Shi X Y,Zhou X Q,Huang K J.2019. Shallow-marine ironstones formed by microaerophilic iron-oxidizing bacteria in terminal Paleoproterozoic. Gondwana Research, 76: 1-18. [33] Luan X C,Brett C E,Zhan R B,Jin J S,Wu R C,Gong F Y.2018. Middle-Late Ordovician iron-rich nodules on Yangtze platform,south China and their palaeoenvironmental implications. Lethaia, 51(4): 523-536. [34] Lawrence M G,Greig A,Collerson K D,Kamber B S K.2006. Direct quantification of rare earth element concentrations in natural waters by ICP-MS. Applied Geochemistry, 21: 839-848. [35] McLennan S M.1994. Rare earth element geochemistry and the “tetrad”effect. Geochimica et Cosmochimica Acta, 58(9): 2025-2033. [36] Qiu Y F,Zhao T P,Li Y L.2020. The Yunmengshan iron formation at the end of the Paleoproterozoic era. Applied Clay Science, 199: 105888. [37] Qiu Y F,Qin L P,Huang F,Zhao T P,Li Y L.2022. Early prosperity of iron bacteria at the end of the Paleoproterozoic era. Geophysical Research Letters, 49: e2022GL097877. [38] Rahiminejad A H,Zand-Moghadam H.2018. Synsedimentary formation of ooidal ironstone: an example from the Jurassic deposits of SE central Iran. Ore Geology Reviews, 95: 238-257. [39] Salama W,El Aref M,Gaupp R.2014. Facies analysis and palaeoclimatic significance of iron stones formed during the Eocene greenhouse. Sedimentology, 61: 1594-1624. [40] Sturesson U,Heikoop J M,Risk M J.2000. Modern and Palaeozoic iron ooids: a similar volcanic origin. Sedimentary Geology, 136: 137-146. [41] Xie B Z,Lechte M,Shi X Y,Wang X,Zhou L M,Zhou X Q,Huang K J,Wang Z F,Wang X Q,Tang D J.2024. Marine aluminum phosphate-sulfate authigenesis as aphosphorus sink during mid-Proterozoic oxygenation. Geophysical Research Letters, 51(4): e2023GL107512. [42] Yang X Q,Mao J W,Poulton S W,Dong A G,Liang T,Wang D C,Zhang X S.2021. The origin of early-Paleozoic banded iron formations in NW China. Gondwana Research, 93: 218-226. [43] Young T P.1989. Phanerozoic iron stones: an introduction and review. Geological Society,London,Special Publications, 46: ix-xxv. [44] Zhang X Y,Qi Y A,Li Y,Dai M Y,Wang M.2020. Ferruginous microbialite blooms of the Miaolingian(Cambrian)in the southern North China craton: a response to the volcanic event?Carbonates and Evaporites, 35: 99.
